Merge pull request #3 from RT-Thread/master

111

61 files changed, 3748 insertions, 1238 deletions

diff --git a/components/net/freemodbus-v1.6.0/port/portserial.c b/components/net/freemodbus-v1.6.0/port/portserial.c
deleted file mode 100644
index 3768702087..0000000000
--- a/components/net/freemodbus-v1.6.0/port/portserial.c
+++ /dev/null
@@ -1,189 +0,0 @@
-/*
- * FreeModbus Libary: STM32 Port
- * Copyright (C) 2013 Armink <[email protected]>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
- *
- * File: $Id: portserial.c,v 1.60 2013/08/13 15:07:05 Armink $
- */
-
-#include "port.h"
-
-/* ----------------------- Modbus includes ----------------------------------*/
-#include "mb.h"
-#include "mbport.h"
-/* ----------------------- static functions ---------------------------------*/
-static void prvvUARTTxReadyISR(void);
-static void prvvUARTRxISR(void);
-/* ----------------------- Start implementation -----------------------------*/
-
-void vMBPortSerialEnable(BOOL xRxEnable, BOOL xTxEnable)
-{
-	if (xRxEnable)
-	{
-		SLAVE_RS485_RECEIVE_MODE;
-		USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
-	}
-	else
-	{
-		SLAVE_RS485_SEND_MODE;
-		USART_ITConfig(USART1, USART_IT_RXNE, DISABLE);
-	}
-	if (xTxEnable)
-	{
-		USART_ITConfig(USART1, USART_IT_TXE, ENABLE);
-	}
-	else
-	{
-		USART_ITConfig(USART1, USART_IT_TXE, DISABLE);
-	}
-}
-
-void vMBPortClose(void)
-{
-	USART_ITConfig(USART1, USART_IT_TXE | USART_IT_RXNE, DISABLE);
-	USART_Cmd(USART1, DISABLE);
-}
-//Ĭ��һ���ӻ� ����1 �����ʿ�����  ��ż���������
-BOOL xMBPortSerialInit(UCHAR ucPORT, ULONG ulBaudRate, UCHAR ucDataBits,
-		eMBParity eParity)
-{
-	GPIO_InitTypeDef GPIO_InitStructure;
-	USART_InitTypeDef USART_InitStructure;
-	NVIC_InitTypeDef NVIC_InitStructure;
-	//======================ʱ�ӳ�ʼ��=======================================
-	RCC_APB2PeriphClockCmd(
-			RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB | RCC_APB2Periph_USART1,
-			ENABLE);
-	//======================IO��ʼ��=======================================	
-	//USART1_TX
-	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
-	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
-	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
-	GPIO_Init(GPIOA, &GPIO_InitStructure);
-	//USART1_RX
-	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
-	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
-	GPIO_Init(GPIOA, &GPIO_InitStructure);
-	//����485���ͺͽ���ģʽ
-//    TODO   ��ʱ��дB13 ��֮����������ʱ���޸�
-	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
-	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13;
-	GPIO_Init(GPIOB, &GPIO_InitStructure);
-	//======================���ڳ�ʼ��=======================================
-	USART_InitStructure.USART_BaudRate = ulBaudRate;
-	//����У��ģʽ
-	switch (eParity)
-	{
-	case MB_PAR_NONE: //����
-		USART_InitStructure.USART_Parity = USART_Parity_No;
-		USART_InitStructure.USART_WordLength = USART_WordLength_8b;
-		break;
-	case MB_PAR_ODD: //����
-		USART_InitStructure.USART_Parity = USART_Parity_Odd;
-		USART_InitStructure.USART_WordLength = USART_WordLength_9b;
-		break;
-	case MB_PAR_EVEN: //żУ��
-		USART_InitStructure.USART_Parity = USART_Parity_Even;
-		USART_InitStructure.USART_WordLength = USART_WordLength_9b;
-		break;
-	default:
-		return FALSE;
-	}
-
-	USART_InitStructure.USART_StopBits = USART_StopBits_1;
-	USART_InitStructure.USART_HardwareFlowControl =
-			USART_HardwareFlowControl_None;
-	USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
-	if (ucPORT != 1)
-		return FALSE;
-
-	ENTER_CRITICAL_SECTION(); //��ȫ���ж�
-
-	USART_Init(USART1, &USART_InitStructure);
-	USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
-	USART_Cmd(USART1, ENABLE);
-
-	//=====================�жϳ�ʼ��======================================
-	//����NVIC���ȼ�����ΪGroup2��0-3��ռʽ���ȼ���0-3����Ӧʽ���ȼ�
-	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
-	NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
-	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
-	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
-	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
-	NVIC_Init(&NVIC_InitStructure);
-
-	EXIT_CRITICAL_SECTION(); //��ȫ���ж�
-
-	return TRUE;
-}
-
-BOOL xMBPortSerialPutByte(CHAR ucByte)
-{
-	USART_SendData(USART1, ucByte);
-	return TRUE;
-}
-
-BOOL xMBPortSerialGetByte(CHAR * pucByte)
-{
-	*pucByte = USART_ReceiveData(USART1);
-	return TRUE;
-}
-
-/* 
- * Create an interrupt handler for the transmit buffer empty interrupt
- * (or an equivalent) for your target processor. This function should then
- * call pxMBFrameCBTransmitterEmpty( ) which tells the protocol stack that
- * a new character can be sent. The protocol stack will then call 
- * xMBPortSerialPutByte( ) to send the character.
- */
-void prvvUARTTxReadyISR(void)
-{
-	pxMBFrameCBTransmitterEmpty();
-}
-
-/* 
- * Create an interrupt handler for the receive interrupt for your target
- * processor. This function should then call pxMBFrameCBByteReceived( ). The
- * protocol stack will then call xMBPortSerialGetByte( ) to retrieve the
- * character.
- */
-void prvvUARTRxISR(void)
-{
-	pxMBFrameCBByteReceived();
-}
-/*******************************************************************************
- * Function Name  : USART1_IRQHandler
- * Description    : This function handles USART1 global interrupt request.
- * Input          : None
- * Output         : None
- * Return         : None
- *******************************************************************************/
-void USART1_IRQHandler(void)
-{
-	rt_interrupt_enter();
-	//�����ж�
-	if (USART_GetITStatus(USART1, USART_IT_RXNE) == SET)
-	{
-		USART_ClearITPendingBit(USART1, USART_IT_RXNE);
-		prvvUARTRxISR();
-	}
-	//�����ж�
-	if (USART_GetITStatus(USART1, USART_IT_TXE) == SET)
-	{
-		prvvUARTTxReadyISR();
-	}
-	rt_interrupt_leave();
-}
diff --git a/components/net/freemodbus-v1.6.0/port/portserial_m.c b/components/net/freemodbus-v1.6.0/port/portserial_m.c
deleted file mode 100644
index ca76a81963..0000000000
--- a/components/net/freemodbus-v1.6.0/port/portserial_m.c
+++ /dev/null
@@ -1,192 +0,0 @@
-/*
- * FreeModbus Libary: STM32 Port
- * Copyright (C) 2013 Armink <[email protected]>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
- *
- * File: $Id: portserial_m.c,v 1.60 2013/08/13 15:07:05 Armink add Master Functions $
- */
-
-#include "port.h"
-
-/* ----------------------- Modbus includes ----------------------------------*/
-#include "mb.h"
-#include "mbport.h"
-
-#if MB_MASTER_RTU_ENABLED > 0 || MB_MASTER_ASCII_ENABLED
-/* ----------------------- static functions ---------------------------------*/
-static void prvvUARTTxReadyISR(void);
-static void prvvUARTRxISR(void);
-/* ----------------------- Start implementation -----------------------------*/
-
-void vMBMasterPortSerialEnable(BOOL xRxEnable, BOOL xTxEnable)
-{
-	if (xRxEnable)
-	{
-		MASTER_RS485_RECEIVE_MODE;
-		USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);
-	}
-	else
-	{
-		MASTER_RS485_SEND_MODE;
-		USART_ITConfig(USART2, USART_IT_RXNE, DISABLE);
-	}
-	if (xTxEnable)
-	{
-		USART_ITConfig(USART2, USART_IT_TXE, ENABLE);
-	}
-	else
-	{
-		USART_ITConfig(USART2, USART_IT_TXE, DISABLE);
-	}
-}
-
-void vMBMasterPortClose(void)
-{
-	USART_ITConfig(USART2, USART_IT_TXE | USART_IT_RXNE, DISABLE);
-	USART_Cmd(USART2, DISABLE);
-}
-//Ĭ��һ������ ����2 �����ʿ�����  ��ż���������
-BOOL xMBMasterPortSerialInit(UCHAR ucPORT, ULONG ulBaudRate, UCHAR ucDataBits,
-		eMBParity eParity)
-{
-	GPIO_InitTypeDef GPIO_InitStructure;
-	USART_InitTypeDef USART_InitStructure;
-	NVIC_InitTypeDef NVIC_InitStructure;
-	//======================ʱ�ӳ�ʼ��=======================================
-	RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB, ENABLE);
-	RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);
-	//======================IO��ʼ��=======================================	
-	//USART2_TX
-	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
-	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
-	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2;
-	GPIO_Init(GPIOA, &GPIO_InitStructure);
-	//USART2_RX
-	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
-	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_3;
-	GPIO_Init(GPIOA, &GPIO_InitStructure);
-	//����485���ͺͽ���ģʽ
-//    TODO   ��ʱ��дB13 ��֮����������ʱ���޸�
-	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
-	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13;
-	GPIO_Init(GPIOB, &GPIO_InitStructure);
-	//======================���ڳ�ʼ��=======================================
-	USART_InitStructure.USART_BaudRate = ulBaudRate;
-	//����У��ģʽ
-	switch (eParity)
-	{
-	case MB_PAR_NONE: //����
-		USART_InitStructure.USART_Parity = USART_Parity_No;
-		USART_InitStructure.USART_WordLength = USART_WordLength_8b;
-		break;
-	case MB_PAR_ODD: //����
-		USART_InitStructure.USART_Parity = USART_Parity_Odd;
-		USART_InitStructure.USART_WordLength = USART_WordLength_9b;
-		break;
-	case MB_PAR_EVEN: //żУ��
-		USART_InitStructure.USART_Parity = USART_Parity_Even;
-		USART_InitStructure.USART_WordLength = USART_WordLength_9b;
-		break;
-	default:
-		return FALSE;
-	}
-
-	USART_InitStructure.USART_StopBits = USART_StopBits_1;
-	USART_InitStructure.USART_HardwareFlowControl =
-			USART_HardwareFlowControl_None;
-	USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
-	if (ucPORT != 2)
-		return FALSE;
-
-	ENTER_CRITICAL_SECTION(); //��ȫ���ж�
-
-	USART_Init(USART2, &USART_InitStructure);
-	USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);
-	USART_Cmd(USART2, ENABLE);
-
-	//=====================�жϳ�ʼ��======================================
-	//����NVIC���ȼ�����ΪGroup2��0-3��ռʽ���ȼ���0-3����Ӧʽ���ȼ�
-	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
-	NVIC_InitStructure.NVIC_IRQChannel = USART2_IRQn;
-	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
-	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
-	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
-	NVIC_Init(&NVIC_InitStructure);
-
-	EXIT_CRITICAL_SECTION(); //��ȫ���ж�
-
-	return TRUE;
-}
-
-BOOL xMBMasterPortSerialPutByte(CHAR ucByte)
-{
-	USART_SendData(USART2, ucByte);
-	return TRUE;
-}
-
-BOOL xMBMasterPortSerialGetByte(CHAR * pucByte)
-{
-	*pucByte = USART_ReceiveData(USART2);
-	return TRUE;
-}
-
-/* 
- * Create an interrupt handler for the transmit buffer empty interrupt
- * (or an equivalent) for your target processor. This function should then
- * call pxMBFrameCBTransmitterEmpty( ) which tells the protocol stack that
- * a new character can be sent. The protocol stack will then call 
- * xMBPortSerialPutByte( ) to send the character.
- */
-void prvvUARTTxReadyISR(void)
-{
-	pxMBMasterFrameCBTransmitterEmpty();
-}
-
-/* 
- * Create an interrupt handler for the receive interrupt for your target
- * processor. This function should then call pxMBFrameCBByteReceived( ). The
- * protocol stack will then call xMBPortSerialGetByte( ) to retrieve the
- * character.
- */
-void prvvUARTRxISR(void)
-{
-	pxMBMasterFrameCBByteReceived();
-}
-/*******************************************************************************
- * Function Name  : USART2_IRQHandler
- * Description    : This function handles USART2 global interrupt request.
- * Input          : None
- * Output         : None
- * Return         : None
- *******************************************************************************/
-void USART2_IRQHandler(void)
-{
-	rt_interrupt_enter();
-	//�����ж�
-	if (USART_GetITStatus(USART2, USART_IT_RXNE) == SET)
-	{
-		USART_ClearITPendingBit(USART2, USART_IT_RXNE);
-		prvvUARTRxISR();
-	}
-	//�����ж�
-	if (USART_GetITStatus(USART2, USART_IT_TXE) == SET)
-	{
-		prvvUARTTxReadyISR();
-	}
-	rt_interrupt_leave();
-}
-
-#endif
diff --git a/components/net/freemodbus-v1.6.0/port/porttimer.c b/components/net/freemodbus-v1.6.0/port/porttimer.c
deleted file mode 100644
index b7b74ce078..0000000000
--- a/components/net/freemodbus-v1.6.0/port/porttimer.c
+++ /dev/null
@@ -1,107 +0,0 @@
-/*
- * FreeModbus Libary: STM32 Port
- * Copyright (C) 2013 Armink <[email protected]>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
- *
- * File: $Id: porttimer.c,v 1.60 2013/08/13 15:07:05 Armink $
- */
-
-/* ----------------------- Platform includes --------------------------------*/
-#include "port.h"
-
-/* ----------------------- Modbus includes ----------------------------------*/
-#include "mb.h"
-#include "mbport.h"
-
-/* ----------------------- static functions ---------------------------------*/
-static void prvvTIMERExpiredISR(void);
-
-/* ----------------------- Start implementation -----------------------------*/
-BOOL xMBPortTimersInit(USHORT usTim1Timerout50us)
-{
-
-	uint16_t PrescalerValue = 0;
-	TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
-	NVIC_InitTypeDef NVIC_InitStructure;
-	//====================================ʱ�ӳ�ʼ��===========================
-	//ʹ�ܶ�ʱ��3ʱ��
-	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
-	//====================================��ʱ����ʼ��===========================
-	//��ʱ��ʱ�������˵��
-	//HCLKΪ72MHz��APB1����2��ƵΪ36MHz
-	//TIM3��ʱ�ӱ�Ƶ��Ϊ72MHz��Ӳ���Զ���Ƶ,�ﵽ���
-	//TIM3�ķ�Ƶϵ��Ϊ3599��ʱ���Ƶ��Ϊ72 / (1 + Prescaler) = 20KHz,��׼Ϊ50us
-	//TIM������ֵΪusTim1Timerout50u
-	
-	PrescalerValue = (uint16_t) (SystemCoreClock / 20000) - 1;
-	//��ʱ��1��ʼ��
-	TIM_TimeBaseStructure.TIM_Period = (uint16_t) usTim1Timerout50us;
-	TIM_TimeBaseStructure.TIM_Prescaler = PrescalerValue;
-	TIM_TimeBaseStructure.TIM_ClockDivision = 0;
-	TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
-	TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);
-	//Ԥװ��ʹ��
-	TIM_ARRPreloadConfig(TIM3, ENABLE);
-	//====================================�жϳ�ʼ��===========================
-	//����NVIC���ȼ�����ΪGroup2��0-3��ռʽ���ȼ���0-3����Ӧʽ���ȼ�
-	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
-	NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn;
-	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
-	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
-	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
-	NVIC_Init(&NVIC_InitStructure);
-	//�������жϱ�־λ
-	TIM_ClearITPendingBit(TIM3, TIM_IT_Update);
-	//��ʱ��3����жϹر�
-	TIM_ITConfig(TIM3, TIM_IT_Update, DISABLE);
-	//��ʱ��3����
-	TIM_Cmd(TIM3, DISABLE);
-	return TRUE;
-}
-
-void vMBPortTimersEnable()
-{
-	TIM_ClearITPendingBit(TIM3, TIM_IT_Update);
-	TIM_ITConfig(TIM3, TIM_IT_Update, ENABLE);
-	TIM_SetCounter(TIM3, 0);
-	TIM_Cmd(TIM3, ENABLE);
-}
-
-void vMBPortTimersDisable()
-{
-	TIM_ClearITPendingBit(TIM3, TIM_IT_Update);
-	TIM_ITConfig(TIM3, TIM_IT_Update, DISABLE);
-	TIM_SetCounter(TIM3, 0);
-	TIM_Cmd(TIM3, DISABLE);
-}
-
-void prvvTIMERExpiredISR(void)
-{
-	(void) pxMBPortCBTimerExpired();
-}
-
-void TIM3_IRQHandler(void)
-{
-	rt_interrupt_enter();
-	if (TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET)
-	{
-		
-		TIM_ClearFlag(TIM3, TIM_FLAG_Update);	     //���жϱ��
-		TIM_ClearITPendingBit(TIM3, TIM_IT_Update);	 //�����ʱ��T3����жϱ�־λ
-		prvvTIMERExpiredISR();
-	}
-	rt_interrupt_leave();
-}
diff --git a/components/net/freemodbus-v1.6.0/port/porttimer_m.c b/components/net/freemodbus-v1.6.0/port/porttimer_m.c
deleted file mode 100644
index 1881b47053..0000000000
--- a/components/net/freemodbus-v1.6.0/port/porttimer_m.c
+++ /dev/null
@@ -1,157 +0,0 @@
-/*
- * FreeModbus Libary: STM32 Port
- * Copyright (C) 2013 Armink <[email protected]>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
- *
- * File: $Id: porttimer_m.c,v 1.60 2013/08/13 15:07:05 Armink add Master Functions$
- */
-
-/* ----------------------- Platform includes --------------------------------*/
-#include "port.h"
-
-/* ----------------------- Modbus includes ----------------------------------*/
-#include "mb.h"
-#include "mb_m.h"
-#include "mbport.h"
-
-#if MB_MASTER_RTU_ENABLED > 0 || MB_MASTER_ASCII_ENABLED
-/* ----------------------- Variables ----------------------------------------*/
-static USHORT usT35TimeOut50us;
-static USHORT usPrescalerValue = 0;
-
-/* ----------------------- static functions ---------------------------------*/
-static void prvvTIMERExpiredISR(void);
-
-/* ----------------------- Start implementation -----------------------------*/
-BOOL xMBMasterPortTimersInit(USHORT usTimeOut50us)
-{
-	NVIC_InitTypeDef NVIC_InitStructure;
-	//====================================ʱ�ӳ�ʼ��===========================
-	//ʹ�ܶ�ʱ��2ʱ��
-	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
-	//====================================��ʱ����ʼ��===========================
-	//��ʱ��ʱ�������˵��
-	//HCLKΪ72MHz��APB1����2��ƵΪ36MHz
-	//TIM2��ʱ�ӱ�Ƶ��Ϊ72MHz��Ӳ���Զ���Ƶ,�ﵽ���
-	//TIM2�ķ�Ƶϵ��Ϊ3599��ʱ���Ƶ��Ϊ72 / (1 + Prescaler) = 20KHz,��׼Ϊ50us
-	//TIM������ֵΪusTim1Timerout50u	
-	usPrescalerValue = (uint16_t) (SystemCoreClock / 20000) - 1;
-	//����T35��ʱ������ֵ
-	usT35TimeOut50us = usTimeOut50us; 
-
-	//Ԥװ��ʹ��
-	TIM_ARRPreloadConfig(TIM2, ENABLE);
-	//====================================�жϳ�ʼ��===========================
-	//����NVIC���ȼ�����ΪGroup2��0-3��ռʽ���ȼ���0-3����Ӧʽ���ȼ�
-	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
-	NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
-	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
-	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
-	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
-	NVIC_Init(&NVIC_InitStructure);
-	//�������жϱ�־λ
-	TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
-	//��ʱ��3����жϹر�
-	TIM_ITConfig(TIM2, TIM_IT_Update, DISABLE);
-	//��ʱ��3����
-	TIM_Cmd(TIM2, DISABLE);
-	return TRUE;
-}
-
-void vMBMasterPortTimersT35Enable()
-{
-	TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
-
-	/* Set current timer mode,don't change it.*/
-	vMBMasterSetCurTimerMode(MB_TMODE_T35);
-
-	TIM_TimeBaseStructure.TIM_Prescaler = usPrescalerValue;
-	TIM_TimeBaseStructure.TIM_ClockDivision = 0;
-	TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
-	TIM_TimeBaseStructure.TIM_Period = (uint16_t) usT35TimeOut50us;
-	TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
-
-	TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
-	TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
-	TIM_SetCounter(TIM2, 0);
-	TIM_Cmd(TIM2, ENABLE);
-}
-
-void vMBMasterPortTimersConvertDelayEnable()
-{
-	TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
-
-	/* Set current timer mode,don't change it.*/
-	vMBMasterSetCurTimerMode(MB_TMODE_CONVERT_DELAY);
-
-	TIM_TimeBaseStructure.TIM_Prescaler = usPrescalerValue;
-	TIM_TimeBaseStructure.TIM_ClockDivision = 0;
-	TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
-	TIM_TimeBaseStructure.TIM_Period = (uint16_t)(MB_MASTER_DELAY_MS_CONVERT * 1000 / 50);
-	TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
-
-	TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
-	TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
-	TIM_SetCounter(TIM2, 0);
-	TIM_Cmd(TIM2, ENABLE);
-}
-
-void vMBMasterPortTimersRespondTimeoutEnable()
-{
-	TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
-
-	/* Set current timer mode,don't change it.*/
-	vMBMasterSetCurTimerMode(MB_TMODE_RESPOND_TIMEOUT);
-
-	TIM_TimeBaseStructure.TIM_Prescaler = usPrescalerValue;
-	TIM_TimeBaseStructure.TIM_ClockDivision = 0;
-	TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
-	TIM_TimeBaseStructure.TIM_Period = (uint16_t)(MB_MASTER_TIMEOUT_MS_RESPOND * 1000 / 50);
-	TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
-
-	TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
-	TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
-	TIM_SetCounter(TIM2, 0);
-	TIM_Cmd(TIM2, ENABLE);
-}
-
-void vMBMasterPortTimersDisable()
-{
-	TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
-	TIM_ITConfig(TIM2, TIM_IT_Update, DISABLE);
-	TIM_SetCounter(TIM2, 0);
-	TIM_Cmd(TIM2, DISABLE);
-}
-
-void prvvTIMERExpiredISR(void)
-{
-	(void) pxMBMasterPortCBTimerExpired();
-}
-
-void TIM2_IRQHandler(void)
-{
-	rt_interrupt_enter();
-	if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET)
-	{
-		
-		TIM_ClearFlag(TIM2, TIM_FLAG_Update);	     //���жϱ��
-		TIM_ClearITPendingBit(TIM2, TIM_IT_Update);	 //�����ʱ��TIM2����жϱ�־λ
-		prvvTIMERExpiredISR();
-	}
-	rt_interrupt_leave();
-}
-
-#endif
diff --git a/components/net/freemodbus-v1.6.0/port/user_mb_app.c b/components/net/freemodbus-v1.6.0/port/user_mb_app.c
deleted file mode 100644
index a99615c235..0000000000
--- a/components/net/freemodbus-v1.6.0/port/user_mb_app.c
+++ /dev/null
@@ -1,349 +0,0 @@
-#include "user_mb_app.h"
-/*------------------------Slave mode use these variables----------------------*/
-//Slave mode:DiscreteInputs variables
-USHORT   usSDiscInStart                               = S_DISCRETE_INPUT_START;
-#if S_DISCRETE_INPUT_NDISCRETES%8
-UCHAR    ucSDiscInBuf[S_DISCRETE_INPUT_NDISCRETES/8+1];
-#else
-UCHAR    ucSDiscInBuf[S_DISCRETE_INPUT_NDISCRETES/8]  ;
-#endif
-//Slave mode:Coils variables
-USHORT   usSCoilStart                                 = S_COIL_START;
-#if S_COIL_NCOILS%8
-UCHAR    ucSCoilBuf[S_COIL_NCOILS/8+1]                ;
-#else
-UCHAR    ucSCoilBuf[S_COIL_NCOILS/8]                  ;
-#endif
-//Slave mode:InputRegister variables
-USHORT   usSRegInStart                                = S_REG_INPUT_START;
-USHORT   usSRegInBuf[S_REG_INPUT_NREGS]               ;
-//Slave mode:HoldingRegister variables
-USHORT   usSRegHoldStart                              = S_REG_HOLDING_START;
-USHORT   usSRegHoldBuf[S_REG_HOLDING_NREGS]           ;
-/*-----------------------Master mode use these variables----------------------*/
-#if MB_MASTER_RTU_ENABLED > 0 || MB_MASTER_ASCII_ENABLED > 0
-//Master mode:DiscreteInputs variables
-USHORT   usMDiscInStart                             = M_DISCRETE_INPUT_START;
-#if      M_DISCRETE_INPUT_NDISCRETES%8
-UCHAR    ucMDiscInBuf[MB_MASTER_TOTAL_SLAVE_NUM][M_DISCRETE_INPUT_NDISCRETES/8+1];
-#else
-UCHAR    ucMDiscInBuf[MB_MASTER_TOTAL_SLAVE_NUM][M_DISCRETE_INPUT_NDISCRETES/8];
-#endif
-//Master mode:Coils variables
-USHORT   usMCoilStart                               = M_COIL_START;
-#if      M_COIL_NCOILS%8
-UCHAR    ucMCoilBuf[MB_MASTER_TOTAL_SLAVE_NUM][M_COIL_NCOILS/8+1];
-#else
-UCHAR    ucMCoilBuf[MB_MASTER_TOTAL_SLAVE_NUM][M_COIL_NCOILS/8];
-#endif
-//Master mode:InputRegister variables
-USHORT   usMRegInStart                              = M_REG_INPUT_START;
-USHORT   usMRegInBuf[MB_MASTER_TOTAL_SLAVE_NUM][M_REG_INPUT_NREGS];
-//Master mode:HoldingRegister variables
-USHORT   usMRegHoldStart                            = M_REG_HOLDING_START;
-USHORT   usMRegHoldBuf[MB_MASTER_TOTAL_SLAVE_NUM][M_REG_HOLDING_NREGS];
-#endif
-//******************************����Ĵ����ص�����**********************************
-//��������: eMBErrorCode eMBRegInputCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNRegs )
-//��    ��������Ĵ�����صĹ��ܣ�������������
-//��ڲ�����pucRegBuffer : �ص�������Modbus�Ĵ����ĵ�ǰֵд��Ļ�����
-//			usAddress    : �Ĵ�������ʼ��ַ������Ĵ����ĵ�ַ��Χ��1-65535��
-//			usNRegs      : �Ĵ�������
-//���ڲ�����eMBErrorCode : ������������صĴ�����
-//��    ע��Editor��Armink 2010-10-31    Company: BXXJS
-//**********************************************************************************
-eMBErrorCode
-eMBRegInputCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNRegs )
-{
-    eMBErrorCode    eStatus = MB_ENOERR;
-    int             iRegIndex;
-    USHORT *        pusRegInputBuf;
-    UCHAR           REG_INPUT_START;
-    UCHAR           REG_INPUT_NREGS;
-    UCHAR           usRegInStart;
-
-    //Determine the master or slave
-    if (xMBMasterGetCBRunInMasterMode())
-    {
-    	pusRegInputBuf = usMRegInBuf[ucMBMasterGetDestAddress()];
-    	REG_INPUT_START = M_REG_INPUT_START;
-    	REG_INPUT_NREGS = M_REG_INPUT_NREGS;
-    	usRegInStart = usMRegInStart;
-    }
-    else
-    {
-    	pusRegInputBuf = usSRegInBuf;
-    	REG_INPUT_START = S_REG_INPUT_START;
-    	REG_INPUT_NREGS = S_REG_INPUT_NREGS;
-    	usRegInStart = usSRegInStart;
-    }
-
-    if( ( usAddress >= REG_INPUT_START )
-        && ( usAddress + usNRegs <= REG_INPUT_START + REG_INPUT_NREGS ) )
-    {
-        iRegIndex = ( int )( usAddress - usRegInStart );
-        while( usNRegs > 0 )
-        {
-            //Determine the master or slave
-            if (xMBMasterGetCBRunInMasterMode())
-            {
-            	pusRegInputBuf[iRegIndex] = *pucRegBuffer++ << 8;
-                pusRegInputBuf[iRegIndex] |= *pucRegBuffer++;
-            }
-            else
-            {
-				*pucRegBuffer++ = ( unsigned char )( pusRegInputBuf[iRegIndex] >> 8 );
-				*pucRegBuffer++ = ( unsigned char )( pusRegInputBuf[iRegIndex] & 0xFF );
-            }
-            iRegIndex++;
-            usNRegs--;
-        }
-    }
-    else
-    {
-        eStatus = MB_ENOREG;
-    }
-
-    return eStatus;
-}
-//******************************���ּĴ����ص�����**********************************
-//��������: eMBErrorCode eMBRegHoldingCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNRegs, eMBRegisterMode eMode )
-//��    �������ּĴ�����صĹ��ܣ�������������д������д��
-//��ڲ�����pucRegBuffer : �����Ҫ�����û��Ĵ�����ֵ���������������ָ���µļĴ�����ֵ��
-//                         ���Э��ջ��֪����ǰ����ֵ���ص��������뽫��ǰֵд�����������
-//			usAddress    : �Ĵ�������ʼ��ַ��
-//			usNRegs      : �Ĵ�������
-//          eMode        : ����ò���ΪeMBRegisterMode::MB_REG_WRITE���û���Ӧ����ֵ����pucRegBuffer�еõ����¡�
-//                         ����ò���ΪeMBRegisterMode::MB_REG_READ���û���Ҫ����ǰ��Ӧ�����ݴ洢��pucRegBuffer��
-//���ڲ�����eMBErrorCode : ������������صĴ�����
-//��    ע��Editor��Armink 2010-10-31    Company: BXXJS
-//**********************************************************************************
-eMBErrorCode
-eMBRegHoldingCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNRegs, eMBRegisterMode eMode )
-{
-    eMBErrorCode    eStatus = MB_ENOERR;
-    int             iRegIndex;
-    USHORT *        pusRegHoldingBuf;
-    UCHAR           REG_HOLDING_START;
-    UCHAR           REG_HOLDING_NREGS;
-    UCHAR           usRegHoldStart;
-
-    //Determine the master or slave
-    if (xMBMasterGetCBRunInMasterMode())
-    {
-    	pusRegHoldingBuf = usMRegHoldBuf[ucMBMasterGetDestAddress()];
-    	REG_HOLDING_START = M_REG_HOLDING_START;
-    	REG_HOLDING_NREGS = M_REG_HOLDING_NREGS;
-    	usRegHoldStart = usMRegHoldStart;
-    	//If mode is read,the master will wirte the received date to bufffer.
-    	eMode = MB_REG_WRITE;
-    }
-    else
-    {
-    	pusRegHoldingBuf = usSRegHoldBuf;
-    	REG_HOLDING_START = S_REG_HOLDING_START;
-    	REG_HOLDING_NREGS = S_REG_HOLDING_NREGS;
-    	usRegHoldStart = usSRegHoldStart;
-    }
-
-    if( ( usAddress >= REG_HOLDING_START ) &&
-        ( usAddress + usNRegs <= REG_HOLDING_START + REG_HOLDING_NREGS ) )
-    {
-        iRegIndex = ( int )( usAddress - usRegHoldStart );
-        switch ( eMode )
-        {
-            /* Pass current register values to the protocol stack. */
-        case MB_REG_READ:
-            while( usNRegs > 0 )
-            {
-				*pucRegBuffer++ = ( unsigned char )( pusRegHoldingBuf[iRegIndex] >> 8 );
-				*pucRegBuffer++ = ( unsigned char )( pusRegHoldingBuf[iRegIndex] & 0xFF );
-                iRegIndex++;
-                usNRegs--;
-            }
-            break;
-
-            /* Update current register values with new values from the
-             * protocol stack. */
-        case MB_REG_WRITE:
-            while( usNRegs > 0 )
-            {
-                pusRegHoldingBuf[iRegIndex] = *pucRegBuffer++ << 8;
-                pusRegHoldingBuf[iRegIndex] |= *pucRegBuffer++;
-                iRegIndex++;
-                usNRegs--;
-            }
-            break;
-        }
-    }
-    else
-    {
-        eStatus = MB_ENOREG;
-    }
-    return eStatus;
-}
-//****************************��Ȧ״̬�Ĵ����ص�����********************************
-//��������: eMBErrorCode eMBRegCoilsCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNCoils, eMBRegisterMode eMode )
-//��    ������Ȧ״̬�Ĵ�����صĹ��ܣ�������������д������д��
-//��ڲ�����pucRegBuffer : λ���һ���ֽڣ���ʼ�Ĵ�����Ӧ��λ���ڸ��ֽ�pucRegBuffer�����λLSB��
-//                         ����ص�����Ҫд�����������û���õ�����Ȧ�����粻��8��һ�����Ȧ״̬����Ӧ��λ����ֵ��������λ0��
-//			usAddress    : ��һ����Ȧ��ַ��
-//			usNCoils     : �������Ȧ����
-//          eMode        ������ò���ΪeMBRegisterMode::MB_REG_WRITE���û���Ӧ����ֵ����pucRegBuffer�еõ����¡�
-//                         ����ò���ΪeMBRegisterMode::MB_REG_READ���û���Ҫ����ǰ��Ӧ�����ݴ洢��pucRegBuffer��
-//���ڲ�����eMBErrorCode : ������������صĴ�����
-//��    ע��Editor��Armink 2010-10-31    Company: BXXJS
-//**********************************************************************************
-eMBErrorCode
-eMBRegCoilsCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNCoils, eMBRegisterMode eMode )
-{
-    eMBErrorCode    eStatus = MB_ENOERR;
-    int             iRegIndex , iRegBitIndex , iNReg;
-	UCHAR *         pucCoilBuf;
-    UCHAR           COIL_START;
-    UCHAR           COIL_NCOILS;
-    UCHAR           usCoilStart;
-    iNReg =  usNCoils / 8 + 1;        //ռ�üĴ�������
-
-
-    //Determine the master or slave
-    if (xMBMasterGetCBRunInMasterMode())
-    {
-    	pucCoilBuf = ucMCoilBuf[ucMBMasterGetDestAddress()];
-    	COIL_START = M_COIL_START;
-    	COIL_NCOILS = M_COIL_NCOILS;
-    	usCoilStart = usMCoilStart;
-    	//If mode is read,the master will wirte the received date to bufffer.
-    	eMode = MB_REG_WRITE;
-    }
-    else
-    {
-    	pucCoilBuf = ucSCoilBuf;
-    	COIL_START = S_COIL_START;
-    	COIL_NCOILS = S_COIL_NCOILS;
-    	usCoilStart = usSCoilStart;
-    }
-
-    if( ( usAddress >= COIL_START ) &&
-        ( usAddress + usNCoils <= COIL_START + COIL_NCOILS ) )
-    {
-        iRegIndex    = ( int )( usAddress - usCoilStart ) / 8 ;    //ÿ���Ĵ�����8��
-		iRegBitIndex = ( int )( usAddress - usCoilStart ) % 8 ;	   //����ڼĴ����ڲ���λ��ַ
-        switch ( eMode )
-        {
-            /* Pass current coil values to the protocol stack. */
-        case MB_REG_READ:
-            while( iNReg > 0 )
-            {
-				*pucRegBuffer++ = xMBUtilGetBits(&pucCoilBuf[iRegIndex++] , iRegBitIndex , 8);
-                iNReg --;
-            }
-			pucRegBuffer --;
-			usNCoils = usNCoils % 8;                        //���µ���Ȧ��	
-			*pucRegBuffer = *pucRegBuffer <<(8 - usNCoils); //�����
-			*pucRegBuffer = *pucRegBuffer >>(8 - usNCoils);
-            break;
-
-            /* Update current coil values with new values from the
-             * protocol stack. */
-        case MB_REG_WRITE:
-            while(iNReg > 1)									 //���������������������
-            {
-				xMBUtilSetBits(&pucCoilBuf[iRegIndex++] , iRegBitIndex  , 8 , *pucRegBuffer++);
-                iNReg--;
-            }
-			usNCoils = usNCoils % 8;                            //���µ���Ȧ��
-			if (usNCoils != 0)                                  //xMBUtilSetBits���� �ڲ���λ����Ϊ0ʱ����bug
-			{
-				xMBUtilSetBits(&pucCoilBuf[iRegIndex++], iRegBitIndex, usNCoils,
-						*pucRegBuffer++);
-			}
-			break;
-        }
-    }
-    else
-    {
-        eStatus = MB_ENOREG;
-    }
-    return eStatus;
-}
-//****************************��ɢ����Ĵ����ص�����********************************
-//��������: eMBErrorCode eMBRegDiscreteCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNDiscrete )
-//��    ������ɢ����Ĵ�����صĹ��ܣ�������������
-//��ڲ�����pucRegBuffer : �õ�ǰ����Ȧ���ݸ�������Ĵ�������ʼ�Ĵ�����Ӧ��λ���ڸ��ֽ�pucRegBuffer�����λLSB��
-//                         ����ص�����Ҫд�����������û���õ�����Ȧ�����粻��8��һ�����Ȧ״̬����Ӧ��λ����ֵ��������Ϊ0��
-//			usAddress    : ��ɢ�������ʼ��ַ
-//			usNDiscrete  : ��ɢ���������
-//���ڲ�����eMBErrorCode : ������������صĴ�����
-//��    ע��Editor��Armink 2010-10-31    Company: BXXJS
-//**********************************************************************************
-eMBErrorCode
-eMBRegDiscreteCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNDiscrete )
-{
-    eMBErrorCode    eStatus = MB_ENOERR;
-	int             iRegIndex , iRegBitIndex , iNReg;
-	UCHAR *         pucDiscreteInputBuf;
-    UCHAR           DISCRETE_INPUT_START;
-    UCHAR           DISCRETE_INPUT_NDISCRETES;
-    UCHAR           usDiscreteInputStart;
-	iNReg =  usNDiscrete / 8 + 1;        //ռ�üĴ�������
-
-    //Determine the master or slave
-    if (xMBMasterGetCBRunInMasterMode())
-    {
-    	pucDiscreteInputBuf = ucMDiscInBuf[ucMBMasterGetDestAddress()];
-    	DISCRETE_INPUT_START = M_DISCRETE_INPUT_START;
-    	DISCRETE_INPUT_NDISCRETES = M_DISCRETE_INPUT_NDISCRETES;
-    	usDiscreteInputStart = usMDiscInStart;
-    }
-    else
-    {
-    	pucDiscreteInputBuf = ucSDiscInBuf;
-    	DISCRETE_INPUT_START = S_DISCRETE_INPUT_START;
-    	DISCRETE_INPUT_NDISCRETES = S_DISCRETE_INPUT_NDISCRETES;
-    	usDiscreteInputStart = usSDiscInStart;
-    }
-
-    if( ( usAddress >= DISCRETE_INPUT_START )
-        && ( usAddress + usNDiscrete <= DISCRETE_INPUT_START + DISCRETE_INPUT_NDISCRETES ) )
-    {
-        iRegIndex    = ( int )( usAddress - usDiscreteInputStart ) / 8 ;    //ÿ���Ĵ�����8��
-		iRegBitIndex = ( int )( usAddress - usDiscreteInputStart ) % 8 ;	   //����ڼĴ����ڲ���λ��ַ
-
-	    //Determine the master or slave
-	    if (xMBMasterGetCBRunInMasterMode())
-	    {
-			/* Update current coil values with new values from the
-			 * protocol stack. */
-			while(iNReg > 1)									 //���������������������
-			{
-				xMBUtilSetBits(&pucDiscreteInputBuf[iRegIndex++] , iRegBitIndex  , 8 , *pucRegBuffer++);
-				iNReg--;
-			}
-			usNDiscrete = usNDiscrete % 8;                        //���µ���Ȧ��
-			if (usNDiscrete != 0)                                 //xMBUtilSetBits���� �ڲ���λ����Ϊ0ʱ����bug
-			{
-				xMBUtilSetBits(&pucDiscreteInputBuf[iRegIndex++], iRegBitIndex,
-						usNDiscrete, *pucRegBuffer++);
-			}
-	    }
-	    else
-	    {
-			while( iNReg > 0 )
-			{
-				*pucRegBuffer++ = xMBUtilGetBits(&pucDiscreteInputBuf[iRegIndex++] , iRegBitIndex , 8);
-				iNReg --;
-			}
-			pucRegBuffer --;
-			usNDiscrete = usNDiscrete % 8;                     //���µ���Ȧ��
-			*pucRegBuffer = *pucRegBuffer <<(8 - usNDiscrete); //�����
-			*pucRegBuffer = *pucRegBuffer >>(8 - usNDiscrete);
-	    }
-    }
-    else
-    {
-        eStatus = MB_ENOREG;
-    }
-
-    return eStatus;
-}
diff --git a/components/net/freemodbus-v1.6.0/port/user_mb_app.h b/components/net/freemodbus-v1.6.0/port/user_mb_app.h
deleted file mode 100644
index 440ca82135..0000000000
--- a/components/net/freemodbus-v1.6.0/port/user_mb_app.h
+++ /dev/null
@@ -1,54 +0,0 @@
-#ifndef	USER_APP
-#define USER_APP
-/* ----------------------- Modbus includes ----------------------------------*/
-#include "mb.h"
-#include "mb_m.h"
-#include "mbconfig.h"
-#include "mbframe.h"
-#include "mbutils.h"
-
-/* -----------------------Slave Defines -------------------------------------*/
-#define S_DISCRETE_INPUT_START        1
-#define S_DISCRETE_INPUT_NDISCRETES   16
-#define S_COIL_START                  1
-#define S_COIL_NCOILS                 64
-#define S_REG_INPUT_START             1
-#define S_REG_INPUT_NREGS             100
-#define S_REG_HOLDING_START           1
-#define S_REG_HOLDING_NREGS           100
-//�ӻ�ģʽ���ڱ��ּĴ����У�������ַ��Ӧ�Ĺ��ܶ���
-#define          S_HD_RESERVE                     0		  //����
-#define          S_HD_CPU_USAGE_MAJOR             1         //��ǰCPU�����ʵ�����λ
-#define          S_HD_CPU_USAGE_MINOR             2         //��ǰCPU�����ʵ�С��λ
-
-//�ӻ�ģʽ��������Ĵ����У�������ַ��Ӧ�Ĺ��ܶ���
-#define          S_IN_RESERVE                     0		  //����
-
-//�ӻ�ģʽ������Ȧ�У�������ַ��Ӧ�Ĺ��ܶ���
-#define          S_CO_RESERVE                     2		  //����
-
-//�ӻ�ģʽ������ɢ�����У�������ַ��Ӧ�Ĺ��ܶ���
-#define          S_DI_RESERVE                     1		  //����
-
-/* -----------------------Master Defines -------------------------------------*/
-#define M_DISCRETE_INPUT_START        1
-#define M_DISCRETE_INPUT_NDISCRETES   16
-#define M_COIL_START                  1
-#define M_COIL_NCOILS                 64
-#define M_REG_INPUT_START             1
-#define M_REG_INPUT_NREGS             100
-#define M_REG_HOLDING_START           1
-#define M_REG_HOLDING_NREGS           100
-//����ģʽ���ڱ��ּĴ����У�������ַ��Ӧ�Ĺ��ܶ���
-#define          M_HD_RESERVE                     0		  //����
-
-//����ģʽ��������Ĵ����У�������ַ��Ӧ�Ĺ��ܶ���
-#define          M_IN_RESERVE                     0		  //����
-
-//����ģʽ������Ȧ�У�������ַ��Ӧ�Ĺ��ܶ���
-#define          M_CO_RESERVE                     2		  //����
-
-//����ģʽ������ɢ�����У�������ַ��Ӧ�Ĺ��ܶ���
-#define          M_DI_RESERVE                     1		  //����
-
-#endif
diff --git a/components/net/freemodbus-v1.6.0/Changelog.txt b/components/net/freemodbus/Changelog.txt
index 2816ea30f3..2816ea30f3 100644
--- a/components/net/freemodbus-v1.6.0/Changelog.txt
+++ b/components/net/freemodbus/Changelog.txt
diff --git a/components/net/freemodbus-v1.6.0/SConscript b/components/net/freemodbus/SConscript
index 77ab37e086..d613a9f398 100644
--- a/components/net/freemodbus-v1.6.0/SConscript
+++ b/components/net/freemodbus/SConscript
@@ -7,7 +7,6 @@ modbus/functions/mbutils.c
 modbus/functions/mbfuncother.c
 modbus/rtu/mbcrc.c
 port/port.c
-port/user_mb_app.c
 """)
 
 master_rtu_src = Split("""
@@ -20,6 +19,7 @@ modbus/mb_m.c
 port/portevent_m.c
 port/portserial_m.c
 port/porttimer_m.c
+port/user_mb_app_m.c
 """)
 
 slave_rtu_src = Split("""
@@ -32,6 +32,7 @@ modbus/mb.c
 port/portevent.c
 port/portserial.c
 port/porttimer.c
+port/user_mb_app.c
 """)
 
 master_slave_rtu_src = Split("""
@@ -53,6 +54,8 @@ port/portserial.c
 port/portserial_m.c
 port/porttimer.c
 port/porttimer_m.c
+port/user_mb_app.c
+port/user_mb_app_m.c
 """)
 
 # The set of source files associated with this SConscript file.
diff --git a/components/net/freemodbus-v1.6.0/bsd.txt b/components/net/freemodbus/bsd.txt
index 362d3e37c8..362d3e37c8 100644
--- a/components/net/freemodbus-v1.6.0/bsd.txt
+++ b/components/net/freemodbus/bsd.txt
diff --git a/components/net/freemodbus-v1.6.0/gpl.txt b/components/net/freemodbus/gpl.txt
index 3912109b5c..3912109b5c 100644
--- a/components/net/freemodbus-v1.6.0/gpl.txt
+++ b/components/net/freemodbus/gpl.txt
diff --git a/components/net/freemodbus-v1.6.0/lgpl.txt b/components/net/freemodbus/lgpl.txt
index 8add30ad59..8add30ad59 100644
--- a/components/net/freemodbus-v1.6.0/lgpl.txt
+++ b/components/net/freemodbus/lgpl.txt
diff --git a/components/net/freemodbus-v1.6.0/modbus/ascii/mbascii.c b/components/net/freemodbus/modbus/ascii/mbascii.c
index b0f3bc05d2..b0f3bc05d2 100644
--- a/components/net/freemodbus-v1.6.0/modbus/ascii/mbascii.c
+++ b/components/net/freemodbus/modbus/ascii/mbascii.c
diff --git a/components/net/freemodbus-v1.6.0/modbus/ascii/mbascii.h b/components/net/freemodbus/modbus/ascii/mbascii.h
index cdec83ff00..cdec83ff00 100644
--- a/components/net/freemodbus-v1.6.0/modbus/ascii/mbascii.h
+++ b/components/net/freemodbus/modbus/ascii/mbascii.h
diff --git a/components/net/freemodbus-v1.6.0/modbus/functions/mbfunccoils.c b/components/net/freemodbus/modbus/functions/mbfunccoils.c
index 681bd50656..681bd50656 100644
--- a/components/net/freemodbus-v1.6.0/modbus/functions/mbfunccoils.c
+++ b/components/net/freemodbus/modbus/functions/mbfunccoils.c
diff --git a/components/net/freemodbus-v1.6.0/modbus/functions/mbfunccoils_m.c b/components/net/freemodbus/modbus/functions/mbfunccoils_m.c
index 553f57b1b7..f6bb51cdf6 100644
--- a/components/net/freemodbus-v1.6.0/modbus/functions/mbfunccoils_m.c
+++ b/components/net/freemodbus/modbus/functions/mbfunccoils_m.c
@@ -74,14 +74,24 @@ eMBException    prveMBError2Exception( eMBErrorCode eErrorCode );
 #if MB_MASTER_RTU_ENABLED > 0 || MB_MASTER_ASCII_ENABLED > 0
 #if MB_FUNC_READ_COILS_ENABLED > 0
 
+/**
+ * This function will request read coil.
+ *
+ * @param ucSndAddr salve address
+ * @param usCoilAddr coil start address
+ * @param usNCoils coil total number
+ * @param lTimeOut timeout (-1 will waiting forever)
+ *
+ * @return error code
+ */
 eMBMasterReqErrCode
-eMBMasterReqReadCoils( UCHAR ucSndAddr, USHORT usCoilAddr, USHORT usNCoils )
+eMBMasterReqReadCoils( UCHAR ucSndAddr, USHORT usCoilAddr, USHORT usNCoils ,LONG lTimeOut )
 {
     UCHAR                 *ucMBFrame;
     eMBMasterReqErrCode    eErrStatus = MB_MRE_NO_ERR;
 
-    if ( xMBMasterGetIsBusy() ) eErrStatus = MB_MRE_MASTER_BUSY;
-    else if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    else if ( xMBMasterRunResTake( lTimeOut ) == FALSE ) eErrStatus = MB_MRE_MASTER_BUSY;
     else
     {
 		vMBMasterGetPDUSndBuf(&ucMBFrame);
@@ -93,6 +103,8 @@ eMBMasterReqReadCoils( UCHAR ucSndAddr, USHORT usCoilAddr, USHORT usNCoils )
 		ucMBFrame[MB_PDU_REQ_READ_COILCNT_OFF + 1] = usNCoils;
 		vMBMasterSetPDUSndLength( MB_PDU_SIZE_MIN + MB_PDU_REQ_READ_SIZE );
 		( void ) xMBMasterPortEventPost( EV_MASTER_FRAME_SENT );
+		eErrStatus = eMBMasterWaitRequestFinish( );
+
     }
     return eErrStatus;
 }
@@ -108,7 +120,12 @@ eMBMasterFuncReadCoils( UCHAR * pucFrame, USHORT * usLen )
     eMBException    eStatus = MB_EX_NONE;
     eMBErrorCode    eRegStatus;
 
-    if( *usLen >= MB_PDU_SIZE_MIN + MB_PDU_FUNC_READ_SIZE_MIN )
+    /* If this request is broadcast, and it's read mode. This request don't need execute. */
+    if ( xMBMasterRequestIsBroadcast() )
+    {
+    	eStatus = MB_EX_NONE;
+    }
+    else if ( *usLen >= MB_PDU_SIZE_MIN + MB_PDU_FUNC_READ_SIZE_MIN )
     {
     	vMBMasterGetPDUSndBuf(&ucMBFrame);
         usRegAddress = ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_ADDR_OFF] << 8 );
@@ -136,7 +153,7 @@ eMBMasterFuncReadCoils( UCHAR * pucFrame, USHORT * usLen )
             ( ucByteCount == pucFrame[MB_PDU_FUNC_READ_COILCNT_OFF] ) )
         {
         	/* Make callback to fill the buffer. */
-            eRegStatus = eMBRegCoilsCB( &pucFrame[MB_PDU_FUNC_READ_VALUES_OFF], usRegAddress, usCoilCount, MB_REG_READ );
+            eRegStatus = eMBMasterRegCoilsCB( &pucFrame[MB_PDU_FUNC_READ_VALUES_OFF], usRegAddress, usCoilCount, MB_REG_READ );
 
             /* If an error occured convert it into a Modbus exception. */
             if( eRegStatus != MB_ENOERR )
@@ -161,15 +178,27 @@ eMBMasterFuncReadCoils( UCHAR * pucFrame, USHORT * usLen )
 
 #if MB_FUNC_WRITE_COIL_ENABLED > 0
 
+/**
+ * This function will request write one coil.
+ *
+ * @param ucSndAddr salve address
+ * @param usCoilAddr coil start address
+ * @param usCoilData data to be written
+ * @param lTimeOut timeout (-1 will waiting forever)
+ *
+ * @return error code
+ *
+ * @see eMBMasterReqWriteMultipleCoils
+ */
 eMBMasterReqErrCode
-eMBMasterReqWriteCoil( UCHAR ucSndAddr, USHORT usCoilAddr, USHORT usCoilData )
+eMBMasterReqWriteCoil( UCHAR ucSndAddr, USHORT usCoilAddr, USHORT usCoilData, LONG lTimeOut )
 {
     UCHAR                 *ucMBFrame;
     eMBMasterReqErrCode    eErrStatus = MB_MRE_NO_ERR;
 
-    if ( xMBMasterGetIsBusy() ) eErrStatus = MB_MRE_MASTER_BUSY;
-    else if ( usCoilAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    if ( usCoilAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
     else if ( ( usCoilData != 0xFF00 ) && ( usCoilData != 0x0000 ) ) eErrStatus = MB_MRE_ILL_ARG;
+    else if ( xMBMasterRunResTake( lTimeOut ) == FALSE ) eErrStatus = MB_MRE_MASTER_BUSY;
     else
     {
 		vMBMasterGetPDUSndBuf(&ucMBFrame);
@@ -181,6 +210,7 @@ eMBMasterReqWriteCoil( UCHAR ucSndAddr, USHORT usCoilAddr, USHORT usCoilData )
 		ucMBFrame[MB_PDU_REQ_WRITE_VALUE_OFF + 1] = usCoilData;
 		vMBMasterSetPDUSndLength( MB_PDU_SIZE_MIN + MB_PDU_REQ_WRITE_SIZE );
 		( void ) xMBMasterPortEventPost( EV_MASTER_FRAME_SENT );
+		eErrStatus = eMBMasterWaitRequestFinish( );
     }
     return eErrStatus;
 }
@@ -214,7 +244,7 @@ eMBMasterFuncWriteCoil( UCHAR * pucFrame, USHORT * usLen )
                 ucBuf[0] = 0;
             }
             eRegStatus =
-                eMBRegCoilsCB( &ucBuf[0], usRegAddress, 1, MB_REG_WRITE );
+                eMBMasterRegCoilsCB( &ucBuf[0], usRegAddress, 1, MB_REG_WRITE );
 
             /* If an error occured convert it into a Modbus exception. */
             if( eRegStatus != MB_ENOERR )
@@ -240,18 +270,31 @@ eMBMasterFuncWriteCoil( UCHAR * pucFrame, USHORT * usLen )
 
 #if MB_FUNC_WRITE_MULTIPLE_COILS_ENABLED > 0
 
+/**
+ * This function will request write multiple coils.
+ *
+ * @param ucSndAddr salve address
+ * @param usCoilAddr coil start address
+ * @param usNCoils coil total number
+ * @param usCoilData data to be written
+ * @param lTimeOut timeout (-1 will waiting forever)
+ *
+ * @return error code
+ *
+ * @see eMBMasterReqWriteCoil
+ */
 eMBMasterReqErrCode
 eMBMasterReqWriteMultipleCoils( UCHAR ucSndAddr,
-		USHORT usCoilAddr, USHORT usNCoils, UCHAR * pucDataBuffer )
+		USHORT usCoilAddr, USHORT usNCoils, UCHAR * pucDataBuffer, LONG lTimeOut)
 {
     UCHAR                 *ucMBFrame;
     USHORT                 usRegIndex = 0;
     UCHAR                  ucByteCount;
     eMBMasterReqErrCode    eErrStatus = MB_MRE_NO_ERR;
 
-    if ( xMBMasterGetIsBusy() ) eErrStatus = MB_MRE_MASTER_BUSY;
-    else if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
     else if ( usNCoils > MB_PDU_REQ_WRITE_MUL_COILCNT_MAX ) eErrStatus = MB_MRE_ILL_ARG;
+    else if ( xMBMasterRunResTake( lTimeOut ) == FALSE ) eErrStatus = MB_MRE_MASTER_BUSY;
     else
     {
 		vMBMasterGetPDUSndBuf(&ucMBFrame);
@@ -277,6 +320,7 @@ eMBMasterReqWriteMultipleCoils( UCHAR ucSndAddr,
 		}
 		vMBMasterSetPDUSndLength( MB_PDU_SIZE_MIN + MB_PDU_REQ_WRITE_MUL_SIZE_MIN + ucByteCount );
 		( void ) xMBMasterPortEventPost( EV_MASTER_FRAME_SENT );
+		eErrStatus = eMBMasterWaitRequestFinish( );
     }
     return eErrStatus;
 }
@@ -293,7 +337,8 @@ eMBMasterFuncWriteMultipleCoils( UCHAR * pucFrame, USHORT * usLen )
     eMBException    eStatus = MB_EX_NONE;
     eMBErrorCode    eRegStatus;
 
-    if( *usLen == MB_PDU_FUNC_WRITE_MUL_SIZE )
+    /* If this request is broadcast, the *usLen is not need check. */
+    if( ( *usLen == MB_PDU_FUNC_WRITE_MUL_SIZE ) || xMBMasterRequestIsBroadcast() )
     {
     	vMBMasterGetPDUSndBuf(&ucMBFrame);
         usRegAddress = ( USHORT )( pucFrame[MB_PDU_FUNC_WRITE_MUL_ADDR_OFF] << 8 );
@@ -318,7 +363,7 @@ eMBMasterFuncWriteMultipleCoils( UCHAR * pucFrame, USHORT * usLen )
         if( ( usCoilCnt >= 1 ) && ( ucByteCountVerify == ucByteCount ) )
         {
             eRegStatus =
-                eMBRegCoilsCB( &ucMBFrame[MB_PDU_REQ_WRITE_MUL_VALUES_OFF],
+                eMBMasterRegCoilsCB( &ucMBFrame[MB_PDU_REQ_WRITE_MUL_VALUES_OFF],
                                usRegAddress, usCoilCnt, MB_REG_WRITE );
 
             /* If an error occured convert it into a Modbus exception. */
diff --git a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncdiag.c b/components/net/freemodbus/modbus/functions/mbfuncdiag.c
index d75ffc0f72..d75ffc0f72 100644
--- a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncdiag.c
+++ b/components/net/freemodbus/modbus/functions/mbfuncdiag.c
diff --git a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncdisc.c b/components/net/freemodbus/modbus/functions/mbfuncdisc.c
index fb378441b9..fb378441b9 100644
--- a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncdisc.c
+++ b/components/net/freemodbus/modbus/functions/mbfuncdisc.c
diff --git a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncdisc_m.c b/components/net/freemodbus/modbus/functions/mbfuncdisc_m.c
index 187872c2a6..6c8d6c4741 100644
--- a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncdisc_m.c
+++ b/components/net/freemodbus/modbus/functions/mbfuncdisc_m.c
@@ -57,16 +57,26 @@ eMBException    prveMBError2Exception( eMBErrorCode eErrorCode );
 
 /* ----------------------- Start implementation -----------------------------*/
 #if MB_MASTER_RTU_ENABLED > 0 || MB_MASTER_ASCII_ENABLED > 0
-#if MB_FUNC_READ_COILS_ENABLED > 0
+#if MB_FUNC_READ_DISCRETE_INPUTS_ENABLED > 0
 
+/**
+ * This function will request read discrete inputs.
+ *
+ * @param ucSndAddr salve address
+ * @param usDiscreteAddr discrete start address
+ * @param usNDiscreteIn discrete total number
+ * @param lTimeOut timeout (-1 will waiting forever)
+ *
+ * @return error code
+ */
 eMBMasterReqErrCode
-eMBMasterReqReadDiscreteInputs( UCHAR ucSndAddr, USHORT usDiscreteAddr, USHORT usNDiscreteIn )
+eMBMasterReqReadDiscreteInputs( UCHAR ucSndAddr, USHORT usDiscreteAddr, USHORT usNDiscreteIn, LONG lTimeOut )
 {
     UCHAR                 *ucMBFrame;
     eMBMasterReqErrCode    eErrStatus = MB_MRE_NO_ERR;
 
-    if ( xMBMasterGetIsBusy() ) eErrStatus = MB_MRE_MASTER_BUSY;
-    else if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    else if ( xMBMasterRunResTake( lTimeOut ) == FALSE ) eErrStatus = MB_MRE_MASTER_BUSY;
     else
     {
 		vMBMasterGetPDUSndBuf(&ucMBFrame);
@@ -78,6 +88,7 @@ eMBMasterReqReadDiscreteInputs( UCHAR ucSndAddr, USHORT usDiscreteAddr, USHORT u
 		ucMBFrame[MB_PDU_REQ_READ_DISCCNT_OFF + 1] = usNDiscreteIn;
 		vMBMasterSetPDUSndLength( MB_PDU_SIZE_MIN + MB_PDU_REQ_READ_SIZE );
 		( void ) xMBMasterPortEventPost( EV_MASTER_FRAME_SENT );
+		eErrStatus = eMBMasterWaitRequestFinish( );
     }
     return eErrStatus;
 }
@@ -93,7 +104,12 @@ eMBMasterFuncReadDiscreteInputs( UCHAR * pucFrame, USHORT * usLen )
     eMBException    eStatus = MB_EX_NONE;
     eMBErrorCode    eRegStatus;
 
-    if( *usLen >= MB_PDU_SIZE_MIN + MB_PDU_FUNC_READ_SIZE_MIN )
+    /* If this request is broadcast, and it's read mode. This request don't need execute. */
+    if ( xMBMasterRequestIsBroadcast() )
+    {
+    	eStatus = MB_EX_NONE;
+    }
+    else if( *usLen >= MB_PDU_SIZE_MIN + MB_PDU_FUNC_READ_SIZE_MIN )
     {
     	vMBMasterGetPDUSndBuf(&ucMBFrame);
         usRegAddress = ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_ADDR_OFF] << 8 );
@@ -120,7 +136,7 @@ eMBMasterFuncReadDiscreteInputs( UCHAR * pucFrame, USHORT * usLen )
 		if ((usDiscreteCnt >= 1) && ucNBytes == pucFrame[MB_PDU_FUNC_READ_DISCCNT_OFF])
         {
 	       	/* Make callback to fill the buffer. */
-			eRegStatus = eMBRegDiscreteCB( &pucFrame[MB_PDU_FUNC_READ_VALUES_OFF], usRegAddress, usDiscreteCnt );
+			eRegStatus = eMBMasterRegDiscreteCB( &pucFrame[MB_PDU_FUNC_READ_VALUES_OFF], usRegAddress, usDiscreteCnt );
 
 			/* If an error occured convert it into a Modbus exception. */
 			if( eRegStatus != MB_ENOERR )
diff --git a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncholding.c b/components/net/freemodbus/modbus/functions/mbfuncholding.c
index e74a0624dc..e74a0624dc 100644
--- a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncholding.c
+++ b/components/net/freemodbus/modbus/functions/mbfuncholding.c
diff --git a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncholding_m.c b/components/net/freemodbus/modbus/functions/mbfuncholding_m.c
index faefbbbb40..e1fe69e383 100644
--- a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncholding_m.c
+++ b/components/net/freemodbus/modbus/functions/mbfuncholding_m.c
@@ -86,14 +86,24 @@ eMBException    prveMBError2Exception( eMBErrorCode eErrorCode );
 #if MB_MASTER_RTU_ENABLED > 0 || MB_MASTER_ASCII_ENABLED > 0
 #if MB_FUNC_WRITE_HOLDING_ENABLED > 0
 
+/**
+ * This function will request write holding register.
+ *
+ * @param ucSndAddr salve address
+ * @param usRegAddr register start address
+ * @param usRegData register data to be written
+ * @param lTimeOut timeout (-1 will waiting forever)
+ *
+ * @return error code
+ */
 eMBMasterReqErrCode
-eMBMasterReqWriteHoldingRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usRegData )
+eMBMasterReqWriteHoldingRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usRegData, LONG lTimeOut )
 {
     UCHAR                 *ucMBFrame;
     eMBMasterReqErrCode    eErrStatus = MB_MRE_NO_ERR;
 
-    if ( xMBMasterGetIsBusy() ) eErrStatus = MB_MRE_MASTER_BUSY;
-    else if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    else if ( xMBMasterRunResTake( lTimeOut ) == FALSE ) eErrStatus = MB_MRE_MASTER_BUSY;
     else
     {
 		vMBMasterGetPDUSndBuf(&ucMBFrame);
@@ -105,6 +115,7 @@ eMBMasterReqWriteHoldingRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usRe
 		ucMBFrame[MB_PDU_REQ_WRITE_VALUE_OFF + 1] = usRegData ;
 		vMBMasterSetPDUSndLength( MB_PDU_SIZE_MIN + MB_PDU_REQ_WRITE_SIZE );
 		( void ) xMBMasterPortEventPost( EV_MASTER_FRAME_SENT );
+		eErrStatus = eMBMasterWaitRequestFinish( );
     }
     return eErrStatus;
 }
@@ -123,7 +134,7 @@ eMBMasterFuncWriteHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
         usRegAddress++;
 
         /* Make callback to update the value. */
-        eRegStatus = eMBRegHoldingCB( &pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF],
+        eRegStatus = eMBMasterRegHoldingCB( &pucFrame[MB_PDU_FUNC_WRITE_VALUE_OFF],
                                       usRegAddress, 1, MB_REG_WRITE );
 
         /* If an error occured convert it into a Modbus exception. */
@@ -143,16 +154,27 @@ eMBMasterFuncWriteHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
 
 #if MB_FUNC_WRITE_MULTIPLE_HOLDING_ENABLED > 0
 
+/**
+ * This function will request write multiple holding register.
+ *
+ * @param ucSndAddr salve address
+ * @param usRegAddr register start address
+ * @param usNRegs register total number
+ * @param pusDataBuffer data to be written
+ * @param lTimeOut timeout (-1 will waiting forever)
+ *
+ * @return error code
+ */
 eMBMasterReqErrCode
 eMBMasterReqWriteMultipleHoldingRegister( UCHAR ucSndAddr,
-		USHORT usRegAddr, USHORT usNRegs, USHORT * pusDataBuffer )
+		USHORT usRegAddr, USHORT usNRegs, USHORT * pusDataBuffer, LONG lTimeOut )
 {
     UCHAR                 *ucMBFrame;
     USHORT                 usRegIndex = 0;
     eMBMasterReqErrCode    eErrStatus = MB_MRE_NO_ERR;
 
-    if ( xMBMasterGetIsBusy() ) eErrStatus = MB_MRE_MASTER_BUSY;
-    else if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    else if ( xMBMasterRunResTake( lTimeOut ) == FALSE ) eErrStatus = MB_MRE_MASTER_BUSY;
     else
     {
 		vMBMasterGetPDUSndBuf(&ucMBFrame);
@@ -171,6 +193,7 @@ eMBMasterReqWriteMultipleHoldingRegister( UCHAR ucSndAddr,
 		}
 		vMBMasterSetPDUSndLength( MB_PDU_SIZE_MIN + MB_PDU_REQ_WRITE_MUL_SIZE_MIN + 2*usNRegs );
 		( void ) xMBMasterPortEventPost( EV_MASTER_FRAME_SENT );
+		eErrStatus = eMBMasterWaitRequestFinish( );
     }
     return eErrStatus;
 }
@@ -186,7 +209,8 @@ eMBMasterFuncWriteMultipleHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
     eMBException    eStatus = MB_EX_NONE;
     eMBErrorCode    eRegStatus;
 
-    if( *usLen == MB_PDU_SIZE_MIN + MB_PDU_FUNC_WRITE_MUL_SIZE )
+    /* If this request is broadcast, the *usLen is not need check. */
+    if( ( *usLen == MB_PDU_SIZE_MIN + MB_PDU_FUNC_WRITE_MUL_SIZE ) || xMBMasterRequestIsBroadcast() )
     {
 		vMBMasterGetPDUSndBuf(&ucMBFrame);
         usRegAddress = ( USHORT )( ucMBFrame[MB_PDU_REQ_WRITE_MUL_ADDR_OFF] << 8 );
@@ -202,7 +226,7 @@ eMBMasterFuncWriteMultipleHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
         {
             /* Make callback to update the register values. */
             eRegStatus =
-                eMBRegHoldingCB( &ucMBFrame[MB_PDU_REQ_WRITE_MUL_VALUES_OFF],
+                eMBMasterRegHoldingCB( &ucMBFrame[MB_PDU_REQ_WRITE_MUL_VALUES_OFF],
                                  usRegAddress, usRegCount, MB_REG_WRITE );
 
             /* If an error occured convert it into a Modbus exception. */
@@ -227,14 +251,24 @@ eMBMasterFuncWriteMultipleHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
 
 #if MB_FUNC_READ_HOLDING_ENABLED > 0
 
+/**
+ * This function will request read holding register.
+ *
+ * @param ucSndAddr salve address
+ * @param usRegAddr register start address
+ * @param usNRegs register total number
+ * @param lTimeOut timeout (-1 will waiting forever)
+ *
+ * @return error code
+ */
 eMBMasterReqErrCode
-eMBMasterReqReadHoldingRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usNRegs )
+eMBMasterReqReadHoldingRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usNRegs, LONG lTimeOut )
 {
     UCHAR                 *ucMBFrame;
     eMBMasterReqErrCode    eErrStatus = MB_MRE_NO_ERR;
 
-    if ( xMBMasterGetIsBusy() ) eErrStatus = MB_MRE_MASTER_BUSY;
-    else if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    else if ( xMBMasterRunResTake( lTimeOut ) == FALSE ) eErrStatus = MB_MRE_MASTER_BUSY;
     else
     {
 		vMBMasterGetPDUSndBuf(&ucMBFrame);
@@ -246,6 +280,7 @@ eMBMasterReqReadHoldingRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usNRe
 		ucMBFrame[MB_PDU_REQ_READ_REGCNT_OFF + 1] = usNRegs;
 		vMBMasterSetPDUSndLength( MB_PDU_SIZE_MIN + MB_PDU_REQ_READ_SIZE );
 		( void ) xMBMasterPortEventPost( EV_MASTER_FRAME_SENT );
+		eErrStatus = eMBMasterWaitRequestFinish( );
     }
     return eErrStatus;
 }
@@ -260,7 +295,12 @@ eMBMasterFuncReadHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
     eMBException    eStatus = MB_EX_NONE;
     eMBErrorCode    eRegStatus;
 
-    if( *usLen >= MB_PDU_SIZE_MIN + MB_PDU_FUNC_READ_SIZE_MIN )
+    /* If this request is broadcast, and it's read mode. This request don't need execute. */
+    if ( xMBMasterRequestIsBroadcast() )
+    {
+    	eStatus = MB_EX_NONE;
+    }
+    else if( *usLen >= MB_PDU_SIZE_MIN + MB_PDU_FUNC_READ_SIZE_MIN )
     {
 		vMBMasterGetPDUSndBuf(&ucMBFrame);
         usRegAddress = ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_ADDR_OFF] << 8 );
@@ -268,7 +308,7 @@ eMBMasterFuncReadHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
         usRegAddress++;
 
         usRegCount = ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_REGCNT_OFF] << 8 );
-        usRegCount = ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_REGCNT_OFF + 1] );
+        usRegCount |= ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_REGCNT_OFF + 1] );
 
         /* Check if the number of registers to read is valid. If not
          * return Modbus illegal data value exception.
@@ -276,7 +316,7 @@ eMBMasterFuncReadHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
         if( ( usRegCount >= 1 ) && ( 2 * usRegCount == pucFrame[MB_PDU_FUNC_READ_BYTECNT_OFF] ) )
         {
             /* Make callback to fill the buffer. */
-            eRegStatus = eMBRegHoldingCB( &pucFrame[MB_PDU_FUNC_READ_VALUES_OFF], usRegAddress, usRegCount, MB_REG_READ );
+            eRegStatus = eMBMasterRegHoldingCB( &pucFrame[MB_PDU_FUNC_READ_VALUES_OFF], usRegAddress, usRegCount, MB_REG_READ );
             /* If an error occured convert it into a Modbus exception. */
             if( eRegStatus != MB_ENOERR )
             {
@@ -300,17 +340,30 @@ eMBMasterFuncReadHoldingRegister( UCHAR * pucFrame, USHORT * usLen )
 
 #if MB_FUNC_READWRITE_HOLDING_ENABLED > 0
 
+/**
+ * This function will request read and write holding register.
+ *
+ * @param ucSndAddr salve address
+ * @param usReadRegAddr read register start address
+ * @param usNReadRegs read register total number
+ * @param pusDataBuffer data to be written
+ * @param usWriteRegAddr write register start address
+ * @param usNWriteRegs write register total number
+ * @param lTimeOut timeout (-1 will waiting forever)
+ *
+ * @return error code
+ */
 eMBMasterReqErrCode
 eMBMasterReqReadWriteMultipleHoldingRegister( UCHAR ucSndAddr,
 		USHORT usReadRegAddr, USHORT usNReadRegs, USHORT * pusDataBuffer,
-		USHORT usWriteRegAddr, USHORT usNWriteRegs )
+		USHORT usWriteRegAddr, USHORT usNWriteRegs, LONG lTimeOut )
 {
     UCHAR                 *ucMBFrame;
     USHORT                 usRegIndex = 0;
     eMBMasterReqErrCode    eErrStatus = MB_MRE_NO_ERR;
 
-    if ( xMBMasterGetIsBusy() ) eErrStatus = MB_MRE_MASTER_BUSY;
-    else if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    else if ( xMBMasterRunResTake( lTimeOut ) == FALSE ) eErrStatus = MB_MRE_MASTER_BUSY;
     else
     {
 		vMBMasterGetPDUSndBuf(&ucMBFrame);
@@ -333,6 +386,7 @@ eMBMasterReqReadWriteMultipleHoldingRegister( UCHAR ucSndAddr,
 		}
 		vMBMasterSetPDUSndLength( MB_PDU_SIZE_MIN + MB_PDU_REQ_READWRITE_SIZE_MIN + 2*usNWriteRegs );
 		( void ) xMBMasterPortEventPost( EV_MASTER_FRAME_SENT );
+		eErrStatus = eMBMasterWaitRequestFinish( );
     }
     return eErrStatus;
 }
@@ -349,7 +403,12 @@ eMBMasterFuncReadWriteMultipleHoldingRegister( UCHAR * pucFrame, USHORT * usLen
     eMBException    eStatus = MB_EX_NONE;
     eMBErrorCode    eRegStatus;
 
-    if( *usLen >= MB_PDU_SIZE_MIN + MB_PDU_FUNC_READWRITE_SIZE_MIN)
+    /* If this request is broadcast, and it's read mode. This request don't need execute. */
+    if ( xMBMasterRequestIsBroadcast() )
+    {
+    	eStatus = MB_EX_NONE;
+    }
+    else if( *usLen >= MB_PDU_SIZE_MIN + MB_PDU_FUNC_READWRITE_SIZE_MIN )
     {
     	vMBMasterGetPDUSndBuf(&ucMBFrame);
         usRegReadAddress = ( USHORT )( ucMBFrame[MB_PDU_REQ_READWRITE_READ_ADDR_OFF] << 8U );
@@ -369,13 +428,13 @@ eMBMasterFuncReadWriteMultipleHoldingRegister( UCHAR * pucFrame, USHORT * usLen
         if( ( 2 * usRegReadCount ) == pucFrame[MB_PDU_FUNC_READWRITE_READ_BYTECNT_OFF] )
         {
             /* Make callback to update the register values. */
-            eRegStatus = eMBRegHoldingCB( &ucMBFrame[MB_PDU_REQ_READWRITE_WRITE_VALUES_OFF],
+            eRegStatus = eMBMasterRegHoldingCB( &ucMBFrame[MB_PDU_REQ_READWRITE_WRITE_VALUES_OFF],
                                            usRegWriteAddress, usRegWriteCount, MB_REG_WRITE );
 
             if( eRegStatus == MB_ENOERR )
             {
                 /* Make the read callback. */
-				eRegStatus = eMBRegHoldingCB(&pucFrame[MB_PDU_FUNC_READWRITE_READ_VALUES_OFF],
+				eRegStatus = eMBMasterRegHoldingCB(&pucFrame[MB_PDU_FUNC_READWRITE_READ_VALUES_OFF],
 						                      usRegReadAddress, usRegReadCount, MB_REG_READ);
             }
             if( eRegStatus != MB_ENOERR )
diff --git a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncinput.c b/components/net/freemodbus/modbus/functions/mbfuncinput.c
index cceedbafea..cceedbafea 100644
--- a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncinput.c
+++ b/components/net/freemodbus/modbus/functions/mbfuncinput.c
diff --git a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncinput_m.c b/components/net/freemodbus/modbus/functions/mbfuncinput_m.c
index e5f362bbec..2127efef67 100644
--- a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncinput_m.c
+++ b/components/net/freemodbus/modbus/functions/mbfuncinput_m.c
@@ -59,14 +59,24 @@ eMBException    prveMBError2Exception( eMBErrorCode eErrorCode );
 #if MB_MASTER_RTU_ENABLED > 0 || MB_MASTER_ASCII_ENABLED > 0
 #if MB_FUNC_READ_INPUT_ENABLED > 0
 
+/**
+ * This function will request read input register.
+ *
+ * @param ucSndAddr salve address
+ * @param usRegAddr register start address
+ * @param usNRegs register total number
+ * @param lTimeOut timeout (-1 will waiting forever)
+ *
+ * @return error code
+ */
 eMBMasterReqErrCode
-eMBMasterReqReadInputRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usNRegs )
+eMBMasterReqReadInputRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usNRegs, LONG lTimeOut )
 {
     UCHAR                 *ucMBFrame;
     eMBMasterReqErrCode    eErrStatus = MB_MRE_NO_ERR;
 
-    if ( xMBMasterGetIsBusy() ) eErrStatus = MB_MRE_MASTER_BUSY;
-    else if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    if ( ucSndAddr > MB_MASTER_TOTAL_SLAVE_NUM ) eErrStatus = MB_MRE_ILL_ARG;
+    else if ( xMBMasterRunResTake( lTimeOut ) == FALSE ) eErrStatus = MB_MRE_MASTER_BUSY;
     else
     {
 		vMBMasterGetPDUSndBuf(&ucMBFrame);
@@ -78,6 +88,7 @@ eMBMasterReqReadInputRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usNRegs
 		ucMBFrame[MB_PDU_REQ_READ_REGCNT_OFF + 1] = usNRegs;
 		vMBMasterSetPDUSndLength( MB_PDU_SIZE_MIN + MB_PDU_REQ_READ_SIZE );
 		( void ) xMBMasterPortEventPost( EV_MASTER_FRAME_SENT );
+		eErrStatus = eMBMasterWaitRequestFinish( );
     }
     return eErrStatus;
 }
@@ -92,7 +103,12 @@ eMBMasterFuncReadInputRegister( UCHAR * pucFrame, USHORT * usLen )
     eMBException    eStatus = MB_EX_NONE;
     eMBErrorCode    eRegStatus;
 
-    if( *usLen >= MB_PDU_SIZE_MIN + MB_PDU_FUNC_READ_SIZE_MIN)
+    /* If this request is broadcast, and it's read mode. This request don't need execute. */
+	if ( xMBMasterRequestIsBroadcast() )
+	{
+		eStatus = MB_EX_NONE;
+	}
+	else if( *usLen >= MB_PDU_SIZE_MIN + MB_PDU_FUNC_READ_SIZE_MIN )
     {
 		vMBMasterGetPDUSndBuf(&ucMBFrame);
         usRegAddress = ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_ADDR_OFF] << 8 );
@@ -100,7 +116,7 @@ eMBMasterFuncReadInputRegister( UCHAR * pucFrame, USHORT * usLen )
         usRegAddress++;
 
         usRegCount = ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_REGCNT_OFF] << 8 );
-        usRegCount = ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_REGCNT_OFF + 1] );
+        usRegCount |= ( USHORT )( ucMBFrame[MB_PDU_REQ_READ_REGCNT_OFF + 1] );
 
         /* Check if the number of registers to read is valid. If not
          * return Modbus illegal data value exception.
@@ -108,7 +124,7 @@ eMBMasterFuncReadInputRegister( UCHAR * pucFrame, USHORT * usLen )
         if( ( usRegCount >= 1 ) && ( 2 * usRegCount == pucFrame[MB_PDU_FUNC_READ_BYTECNT_OFF] ) )
         {
             /* Make callback to fill the buffer. */
-            eRegStatus = eMBRegInputCB( &pucFrame[MB_PDU_FUNC_READ_VALUES_OFF], usRegAddress, usRegCount );
+            eRegStatus = eMBMasterRegInputCB( &pucFrame[MB_PDU_FUNC_READ_VALUES_OFF], usRegAddress, usRegCount );
             /* If an error occured convert it into a Modbus exception. */
             if( eRegStatus != MB_ENOERR )
             {
diff --git a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncother.c b/components/net/freemodbus/modbus/functions/mbfuncother.c
index fcee972bf8..fcee972bf8 100644
--- a/components/net/freemodbus-v1.6.0/modbus/functions/mbfuncother.c
+++ b/components/net/freemodbus/modbus/functions/mbfuncother.c
diff --git a/components/net/freemodbus-v1.6.0/modbus/functions/mbutils.c b/components/net/freemodbus/modbus/functions/mbutils.c
index 4ffbd3e001..4ffbd3e001 100644
--- a/components/net/freemodbus-v1.6.0/modbus/functions/mbutils.c
+++ b/components/net/freemodbus/modbus/functions/mbutils.c
diff --git a/components/net/freemodbus-v1.6.0/modbus/include/mb.h b/components/net/freemodbus/modbus/include/mb.h
index 8d6be7b422..8d6be7b422 100644
--- a/components/net/freemodbus-v1.6.0/modbus/include/mb.h
+++ b/components/net/freemodbus/modbus/include/mb.h
diff --git a/components/net/freemodbus-v1.6.0/modbus/include/mb_m.h b/components/net/freemodbus/modbus/include/mb_m.h
index 9c4fa43e60..f6b25e2cf3 100644
--- a/components/net/freemodbus-v1.6.0/modbus/include/mb_m.h
+++ b/components/net/freemodbus/modbus/include/mb_m.h
@@ -77,13 +77,10 @@ typedef enum
     MB_MRE_NO_ERR,                  /*!< no error. */
     MB_MRE_NO_REG,                  /*!< illegal register address. */
     MB_MRE_ILL_ARG,                 /*!< illegal argument. */
-    MB_MRE_PORT_ERR,                /*!< porting layer error. */
-    MB_MRE_NO_RES,                  /*!< insufficient resources. */
-    MB_MRE_IO,                      /*!< I/O error. */
-    MB_MRE_ILL_STATE,               /*!< protocol stack in illegal state. */
+    MB_MRE_REV_DATA,                /*!< receive data error. */
     MB_MRE_TIMEDOUT,                /*!< timeout error occurred. */
     MB_MRE_MASTER_BUSY,             /*!< master is busy now. */
-    MB_MRE_SLAVE_EXCE               /*!< slave has exception. */
+    MB_MRE_EXE_FUN                  /*!< execute function error. */
 } eMBMasterReqErrCode;
 /*! \ingroup modbus
  *  \brief TimerMode is Master 3 kind of Timer modes.
@@ -189,31 +186,176 @@ eMBErrorCode    eMBMasterDisable( void );
  */
 eMBErrorCode    eMBMasterPoll( void );
 
+/*! \ingroup modbus
+ * \brief Registers a callback handler for a given function code.
+ *
+ * This function registers a new callback handler for a given function code.
+ * The callback handler supplied is responsible for interpreting the Modbus PDU and
+ * the creation of an appropriate response. In case of an error it should return
+ * one of the possible Modbus exceptions which results in a Modbus exception frame
+ * sent by the protocol stack.
+ *
+ * \param ucFunctionCode The Modbus function code for which this handler should
+ *   be registers. Valid function codes are in the range 1 to 127.
+ * \param pxHandler The function handler which should be called in case
+ *   such a frame is received. If \c NULL a previously registered function handler
+ *   for this function code is removed.
+ *
+ * \return eMBErrorCode::MB_ENOERR if the handler has been installed. If no
+ *   more resources are available it returns eMBErrorCode::MB_ENORES. In this
+ *   case the values in mbconfig.h should be adjusted. If the argument was not
+ *   valid it returns eMBErrorCode::MB_EINVAL.
+ */
+eMBErrorCode    eMBMasterRegisterCB( UCHAR ucFunctionCode,
+                               pxMBFunctionHandler pxHandler );
+
+/* ----------------------- Callback -----------------------------------------*/
+
+/*! \defgroup modbus_master registers Modbus Registers
+ * \code #include "mb_m.h" \endcode
+ * The protocol stack does not internally allocate any memory for the
+ * registers. This makes the protocol stack very small and also usable on
+ * low end targets. In addition the values don't have to be in the memory
+ * and could for example be stored in a flash.<br>
+ * Whenever the protocol stack requires a value it calls one of the callback
+ * function with the register address and the number of registers to read
+ * as an argument. The application should then read the actual register values
+ * (for example the ADC voltage) and should store the result in the supplied
+ * buffer.<br>
+ * If the protocol stack wants to update a register value because a write
+ * register function was received a buffer with the new register values is
+ * passed to the callback function. The function should then use these values
+ * to update the application register values.
+ */
+
+/*! \ingroup modbus_registers
+ * \brief Callback function used if the value of a <em>Input Register</em>
+ *   is required by the protocol stack. The starting register address is given
+ *   by \c usAddress and the last register is given by <tt>usAddress +
+ *   usNRegs - 1</tt>.
+ *
+ * \param pucRegBuffer A buffer where the callback function should write
+ *   the current value of the modbus registers to.
+ * \param usAddress The starting address of the register. Input registers
+ *   are in the range 1 - 65535.
+ * \param usNRegs Number of registers the callback function must supply.
+ *
+ * \return The function must return one of the following error codes:
+ *   - eMBErrorCode::MB_ENOERR If no error occurred. In this case a normal
+ *       Modbus response is sent.
+ *   - eMBErrorCode::MB_ENOREG If the application does not map an coils
+ *       within the requested address range. In this case a
+ *       <b>ILLEGAL DATA ADDRESS</b> is sent as a response.
+ */
+eMBErrorCode eMBMasterRegInputCB( UCHAR * pucRegBuffer, USHORT usAddress,
+		USHORT usNRegs );
+
+/*! \ingroup modbus_registers
+ * \brief Callback function used if a <em>Holding Register</em> value is
+ *   read or written by the protocol stack. The starting register address
+ *   is given by \c usAddress and the last register is given by
+ *   <tt>usAddress + usNRegs - 1</tt>.
+ *
+ * \param pucRegBuffer If the application registers values should be updated the
+ *   buffer points to the new registers values. If the protocol stack needs
+ *   to now the current values the callback function should write them into
+ *   this buffer.
+ * \param usAddress The starting address of the register.
+ * \param usNRegs Number of registers to read or write.
+ * \param eMode If eMBRegisterMode::MB_REG_WRITE the application register
+ *   values should be updated from the values in the buffer. For example
+ *   this would be the case when the Modbus master has issued an
+ *   <b>WRITE SINGLE REGISTER</b> command.
+ *   If the value eMBRegisterMode::MB_REG_READ the application should copy
+ *   the current values into the buffer \c pucRegBuffer.
+ *
+ * \return The function must return one of the following error codes:
+ *   - eMBErrorCode::MB_ENOERR If no error occurred. In this case a normal
+ *       Modbus response is sent.
+ *   - eMBErrorCode::MB_ENOREG If the application does not map an coils
+ *       within the requested address range. In this case a
+ *       <b>ILLEGAL DATA ADDRESS</b> is sent as a response.
+ */
+eMBErrorCode eMBMasterRegHoldingCB( UCHAR * pucRegBuffer, USHORT usAddress,
+		USHORT usNRegs, eMBRegisterMode eMode );
+
+/*! \ingroup modbus_registers
+ * \brief Callback function used if a <em>Coil Register</em> value is
+ *   read or written by the protocol stack. If you are going to use
+ *   this function you might use the functions xMBUtilSetBits(  ) and
+ *   xMBUtilGetBits(  ) for working with bitfields.
+ *
+ * \param pucRegBuffer The bits are packed in bytes where the first coil
+ *   starting at address \c usAddress is stored in the LSB of the
+ *   first byte in the buffer <code>pucRegBuffer</code>.
+ *   If the buffer should be written by the callback function unused
+ *   coil values (I.e. if not a multiple of eight coils is used) should be set
+ *   to zero.
+ * \param usAddress The first coil number.
+ * \param usNCoils Number of coil values requested.
+ * \param eMode If eMBRegisterMode::MB_REG_WRITE the application values should
+ *   be updated from the values supplied in the buffer \c pucRegBuffer.
+ *   If eMBRegisterMode::MB_REG_READ the application should store the current
+ *   values in the buffer \c pucRegBuffer.
+ *
+ * \return The function must return one of the following error codes:
+ *   - eMBErrorCode::MB_ENOERR If no error occurred. In this case a normal
+ *       Modbus response is sent.
+ *   - eMBErrorCode::MB_ENOREG If the application does not map an coils
+ *       within the requested address range. In this case a
+ *       <b>ILLEGAL DATA ADDRESS</b> is sent as a response.
+ */
+eMBErrorCode eMBMasterRegCoilsCB( UCHAR * pucRegBuffer, USHORT usAddress,
+		USHORT usNCoils, eMBRegisterMode eMode );
+
+/*! \ingroup modbus_registers
+ * \brief Callback function used if a <em>Input Discrete Register</em> value is
+ *   read by the protocol stack.
+ *
+ * If you are going to use his function you might use the functions
+ * xMBUtilSetBits(  ) and xMBUtilGetBits(  ) for working with bitfields.
+ *
+ * \param pucRegBuffer The buffer should be updated with the current
+ *   coil values. The first discrete input starting at \c usAddress must be
+ *   stored at the LSB of the first byte in the buffer. If the requested number
+ *   is not a multiple of eight the remaining bits should be set to zero.
+ * \param usAddress The starting address of the first discrete input.
+ * \param usNDiscrete Number of discrete input values.
+ * \return The function must return one of the following error codes:
+ *   - eMBErrorCode::MB_ENOERR If no error occurred. In this case a normal
+ *       Modbus response is sent.
+ *   - eMBErrorCode::MB_ENOREG If the application does not map an coils
+ *       within the requested address range. In this case a
+ *       <b>ILLEGAL DATA ADDRESS</b> is sent as a response.
+ */
+eMBErrorCode eMBMasterRegDiscreteCB( UCHAR * pucRegBuffer, USHORT usAddress,
+		USHORT usNDiscrete );
 
 /*! \ingroup modbus
  *\brief These Modbus functions are called for user when Modbus run in Master Mode.
  */
 eMBMasterReqErrCode
-eMBMasterReqReadInputRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usNRegs );
+eMBMasterReqReadInputRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usNRegs, LONG lTimeOut );
 eMBMasterReqErrCode
-eMBMasterReqWriteHoldingRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usRegData );
+eMBMasterReqWriteHoldingRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usRegData, LONG lTimeOut );
 eMBMasterReqErrCode
-eMBMasterReqWriteMultipleHoldingRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usNRegs, USHORT * pusDataBuffer );
+eMBMasterReqWriteMultipleHoldingRegister( UCHAR ucSndAddr, USHORT usRegAddr,
+		USHORT usNRegs, USHORT * pusDataBuffer, LONG lTimeOut );
 eMBMasterReqErrCode
-eMBMasterReqReadHoldingRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usNRegs );
+eMBMasterReqReadHoldingRegister( UCHAR ucSndAddr, USHORT usRegAddr, USHORT usNRegs, LONG lTimeOut );
 eMBMasterReqErrCode
 eMBMasterReqReadWriteMultipleHoldingRegister( UCHAR ucSndAddr,
 		USHORT usReadRegAddr, USHORT usNReadRegs, USHORT * pusDataBuffer,
-		USHORT usWriteRegAddr, USHORT usNWriteRegs );
+		USHORT usWriteRegAddr, USHORT usNWriteRegs, LONG lTimeOut );
 eMBMasterReqErrCode
-eMBMasterReqReadCoils( UCHAR ucSndAddr, USHORT usCoilAddr, USHORT usNCoils );
+eMBMasterReqReadCoils( UCHAR ucSndAddr, USHORT usCoilAddr, USHORT usNCoils, LONG lTimeOut );
 eMBMasterReqErrCode
-eMBMasterReqWriteCoil( UCHAR ucSndAddr, USHORT usCoilAddr, USHORT usCoilData );
+eMBMasterReqWriteCoil( UCHAR ucSndAddr, USHORT usCoilAddr, USHORT usCoilData, LONG lTimeOut );
 eMBMasterReqErrCode
 eMBMasterReqWriteMultipleCoils( UCHAR ucSndAddr,
-		USHORT usCoilAddr, USHORT usNCoils, UCHAR * pucDataBuffer );
+		USHORT usCoilAddr, USHORT usNCoils, UCHAR * pucDataBuffer, LONG lTimeOut );
 eMBMasterReqErrCode
-eMBMasterReqReadDiscreteInputs( UCHAR ucSndAddr, USHORT usDiscreteAddr, USHORT usNDiscreteIn );
+eMBMasterReqReadDiscreteInputs( UCHAR ucSndAddr, USHORT usDiscreteAddr, USHORT usNDiscreteIn, LONG lTimeOut );
 
 eMBException
 eMBMasterFuncReportSlaveID( UCHAR * pucFrame, USHORT * usLen );
@@ -239,16 +381,18 @@ eMBMasterFuncReadWriteMultipleHoldingRegister( UCHAR * pucFrame, USHORT * usLen
 /*�� \ingroup modbus
  *\brief These functions are interface for Modbus Master
  */
-BOOL xMBMasterGetIsBusy( void );
 void vMBMasterGetPDUSndBuf( UCHAR ** pucFrame );
 UCHAR ucMBMasterGetDestAddress( void );
 void vMBMasterSetDestAddress( UCHAR Address );
-void vMBMasterSetIsBusy( BOOL IsBusy );
 BOOL xMBMasterGetCBRunInMasterMode( void );
 void vMBMasterSetCBRunInMasterMode( BOOL IsMasterMode );
-UCHAR ucMBMasterGetPDUSndLength( void );
-void vMBMasterSetPDUSndLength( UCHAR SendPDULength );
+USHORT usMBMasterGetPDUSndLength( void );
+void vMBMasterSetPDUSndLength( USHORT SendPDULength );
 void vMBMasterSetCurTimerMode( eMBMasterTimerMode eMBTimerMode );
+BOOL xMBMasterRequestIsBroadcast( void );
+eMBMasterErrorEventType eMBMasterGetErrorType( void );
+void vMBMasterSetErrorType( eMBMasterErrorEventType errorType );
+eMBMasterReqErrCode eMBMasterWaitRequestFinish( void );
 
 /* ----------------------- Callback -----------------------------------------*/
 
diff --git a/components/net/freemodbus-v1.6.0/modbus/include/mbconfig.h b/components/net/freemodbus/modbus/include/mbconfig.h
index c5434de47e..89030b7abd 100644
--- a/components/net/freemodbus-v1.6.0/modbus/include/mbconfig.h
+++ b/components/net/freemodbus/modbus/include/mbconfig.h
@@ -115,9 +115,9 @@ PR_BEGIN_EXTERN_C
 /*! \brief If master send a frame which is not broadcast,the master will wait sometime for slave.
  * And if slave is not respond in this time,the master will process this timeout error.
  * Then master can send other frame */
-#define MB_MASTER_TIMEOUT_MS_RESPOND            (2000)
-/*! \brief The total slaves in Modbus Master system.Default 16.
- * Note : The slave ID must be continuous from 0.*/
+#define MB_MASTER_TIMEOUT_MS_RESPOND            (100 )
+/*! \brief The total slaves in Modbus Master system. Default 16.
+ * \note : The slave ID must be continuous from 1.*/
 #define MB_MASTER_TOTAL_SLAVE_NUM               ( 16 )
 #endif
 
diff --git a/components/net/freemodbus-v1.6.0/modbus/include/mbframe.h b/components/net/freemodbus/modbus/include/mbframe.h
index 99d59c613e..99d59c613e 100644
--- a/components/net/freemodbus-v1.6.0/modbus/include/mbframe.h
+++ b/components/net/freemodbus/modbus/include/mbframe.h
diff --git a/components/net/freemodbus-v1.6.0/modbus/include/mbfunc.h b/components/net/freemodbus/modbus/include/mbfunc.h
index 3f9c2725a1..3f9c2725a1 100644
--- a/components/net/freemodbus-v1.6.0/modbus/include/mbfunc.h
+++ b/components/net/freemodbus/modbus/include/mbfunc.h
diff --git a/components/net/freemodbus-v1.6.0/modbus/include/mbport.h b/components/net/freemodbus/modbus/include/mbport.h
index a4c0a24dd4..11794a2929 100644
--- a/components/net/freemodbus-v1.6.0/modbus/include/mbport.h
+++ b/components/net/freemodbus/modbus/include/mbport.h
@@ -36,25 +36,38 @@
 PR_BEGIN_EXTERN_C
 #endif
 
+/* ----------------------- Defines ------------------------------------------*/
+
 /* ----------------------- Type definitions ---------------------------------*/
 
 typedef enum
 {
-    EV_READY,                   /*!< Startup finished. */
-    EV_FRAME_RECEIVED,          /*!< Frame received. */
-    EV_EXECUTE,                 /*!< Execute function. */
-    EV_FRAME_SENT               /*!< Frame sent. */
+    EV_READY            = 1<<0,         /*!< Startup finished. */
+    EV_FRAME_RECEIVED   = 1<<1,         /*!< Frame received. */
+    EV_EXECUTE          = 1<<2,         /*!< Execute function. */
+    EV_FRAME_SENT       = 1<<3          /*!< Frame sent. */
 } eMBEventType;
 
 typedef enum
 {
-    EV_MASTER_READY,                   /*!< Startup finished. */
-    EV_MASTER_FRAME_RECEIVED,          /*!< Frame received. */
-    EV_MASTER_EXECUTE,                 /*!< Execute function. */
-    EV_MASTER_FRAME_SENT,              /*!< Frame sent. */
-    EV_MASTER_ERROR_PROCESS            /*!< Frame error process*/
+    EV_MASTER_READY                    = 1<<0,  /*!< Startup finished. */
+    EV_MASTER_FRAME_RECEIVED           = 1<<1,  /*!< Frame received. */
+    EV_MASTER_EXECUTE                  = 1<<2,  /*!< Execute function. */
+    EV_MASTER_FRAME_SENT               = 1<<3,  /*!< Frame sent. */
+    EV_MASTER_ERROR_PROCESS            = 1<<4,  /*!< Frame error process. */
+    EV_MASTER_PROCESS_SUCESS           = 1<<5,  /*!< Request process success. */
+    EV_MASTER_ERROR_RESPOND_TIMEOUT    = 1<<6,  /*!< Request respond timeout. */
+    EV_MASTER_ERROR_RECEIVE_DATA       = 1<<7,  /*!< Request receive data error. */
+    EV_MASTER_ERROR_EXECUTE_FUNCTION   = 1<<8,  /*!< Request execute function error. */
 } eMBMasterEventType;
 
+typedef enum
+{
+    EV_ERROR_RESPOND_TIMEOUT,         /*!< Slave respond timeout. */
+    EV_ERROR_RECEIVE_DATA,            /*!< Receive frame data erroe. */
+    EV_ERROR_EXECUTE_FUNCTION,        /*!< Execute function error. */
+} eMBMasterErrorEventType;
+
 /*! \ingroup modbus
  * \brief Parity used for characters in serial mode.
  *
@@ -82,6 +95,12 @@ BOOL            xMBMasterPortEventPost( eMBMasterEventType eEvent );
 
 BOOL            xMBMasterPortEventGet(  /*@out@ */ eMBMasterEventType * eEvent );
 
+void            vMBMasterOsResInit( void );
+
+BOOL            xMBMasterRunResTake( int32_t time );
+
+void            vMBMasterRunResRelease( void );
+
 /* ----------------------- Serial port functions ----------------------------*/
 
 BOOL            xMBPortSerialInit( UCHAR ucPort, ULONG ulBaudRate,
@@ -97,7 +116,6 @@ INLINE BOOL     xMBPortSerialGetByte( CHAR * pucByte );
 
 INLINE BOOL     xMBPortSerialPutByte( CHAR ucByte );
 
-
 BOOL            xMBMasterPortSerialInit( UCHAR ucPort, ULONG ulBaudRate,
                                    UCHAR ucDataBits, eMBParity eParity );
 
@@ -132,6 +150,18 @@ INLINE void     vMBMasterPortTimersRespondTimeoutEnable( void );
 
 INLINE void     vMBMasterPortTimersDisable( void );
 
+/* ----------------- Callback for the master error process ------------------*/
+void            vMBMasterErrorCBRespondTimeout( UCHAR ucDestAddress, const UCHAR* pucPDUData,
+                                                USHORT ucPDULength );
+
+void            vMBMasterErrorCBReceiveData( UCHAR ucDestAddress, const UCHAR* pucPDUData,
+                                             USHORT ucPDULength );
+
+void            vMBMasterErrorCBExecuteFunction( UCHAR ucDestAddress, const UCHAR* pucPDUData,
+                                                 USHORT ucPDULength );
+
+void            vMBMasterCBRequestScuuess( void );
+
 /* ----------------------- Callback for the protocol stack ------------------*/
 
 /*!
diff --git a/components/net/freemodbus-v1.6.0/modbus/include/mbproto.h b/components/net/freemodbus/modbus/include/mbproto.h
index 786aaf4030..786aaf4030 100644
--- a/components/net/freemodbus-v1.6.0/modbus/include/mbproto.h
+++ b/components/net/freemodbus/modbus/include/mbproto.h
diff --git a/components/net/freemodbus-v1.6.0/modbus/include/mbutils.h b/components/net/freemodbus/modbus/include/mbutils.h
index 61495751d4..61495751d4 100644
--- a/components/net/freemodbus-v1.6.0/modbus/include/mbutils.h
+++ b/components/net/freemodbus/modbus/include/mbutils.h
diff --git a/components/net/freemodbus-v1.6.0/modbus/mb.c b/components/net/freemodbus/modbus/mb.c
index 96d693c910..96d693c910 100644
--- a/components/net/freemodbus-v1.6.0/modbus/mb.c
+++ b/components/net/freemodbus/modbus/mb.c
diff --git a/components/net/freemodbus-v1.6.0/modbus/mb_m.c b/components/net/freemodbus/modbus/mb_m.c
index 8f86f54182..4e7c4b2b74 100644
--- a/components/net/freemodbus-v1.6.0/modbus/mb_m.c
+++ b/components/net/freemodbus/modbus/mb_m.c
@@ -65,7 +65,7 @@
 
 static UCHAR    ucMBMasterDestAddress;
 static BOOL     xMBRunInMasterMode = FALSE;
-static BOOL     xMasterIsBusy = FALSE;
+static eMBMasterErrorEventType eMBMasterCurErrorType;
 
 static enum
 {
@@ -185,6 +185,8 @@ eMBMasterInit( eMBMode eMode, UCHAR ucPort, ULONG ulBaudRate, eMBParity eParity
 		{
 			eMBState = STATE_DISABLED;
 		}
+		/* initialize the OS resource for modbus master. */
+		vMBMasterOsResInit();
 	}
 	return eStatus;
 }
@@ -257,9 +259,10 @@ eMBMasterPoll( void )
     static USHORT   usLength;
     static eMBException eException;
 
-    int             i;
+    int             i , j;
     eMBErrorCode    eStatus = MB_ENOERR;
     eMBMasterEventType    eEvent;
+    eMBMasterErrorEventType errorType;
 
     /* Check if the protocol stack is ready. */
     if( eMBState != STATE_ENABLED )
@@ -285,6 +288,7 @@ eMBMasterPoll( void )
 			}
 			else
 			{
+				vMBMasterSetErrorType(EV_ERROR_RECEIVE_DATA);
 				( void ) xMBMasterPortEventPost( EV_MASTER_ERROR_PROCESS );
 			}
 			break;
@@ -292,52 +296,80 @@ eMBMasterPoll( void )
         case EV_MASTER_EXECUTE:
             ucFunctionCode = ucMBFrame[MB_PDU_FUNC_OFF];
             eException = MB_EX_ILLEGAL_FUNCTION;
-            for( i = 0; i < MB_FUNC_HANDLERS_MAX; i++ )
-            {
-                /* No more function handlers registered. Abort. */
-                if( xMasterFuncHandlers[i].ucFunctionCode == 0 )
-                {
-                    break;
-                }
-                else if( xMasterFuncHandlers[i].ucFunctionCode == ucFunctionCode )
-                {
-                	vMBMasterSetCBRunInMasterMode(TRUE);
-                    eException = xMasterFuncHandlers[i].pxHandler( ucMBFrame, &usLength );
-                    vMBMasterSetCBRunInMasterMode(FALSE);
-                    break;
-                }
-            }
             /* If receive frame has exception .The receive function code highest bit is 1.*/
-            if(ucFunctionCode >> 7) eException = (eMBException)ucMBFrame[MB_PDU_DATA_OFF];
+            if(ucFunctionCode >> 7) {
+            	eException = (eMBException)ucMBFrame[MB_PDU_DATA_OFF];
+            }
+			else
+			{
+				for (i = 0; i < MB_FUNC_HANDLERS_MAX; i++)
+				{
+					/* No more function handlers registered. Abort. */
+					if (xMasterFuncHandlers[i].ucFunctionCode == 0)	{
+						break;
+					}
+					else if (xMasterFuncHandlers[i].ucFunctionCode == ucFunctionCode) {
+						vMBMasterSetCBRunInMasterMode(TRUE);
+						/* If master request is broadcast,
+						 * the master need execute function for all slave.
+						 */
+						if ( xMBMasterRequestIsBroadcast() ) {
+							usLength = usMBMasterGetPDUSndLength();
+							for(j = 1; j <= MB_MASTER_TOTAL_SLAVE_NUM; j++){
+								vMBMasterSetDestAddress(j);
+								eException = xMasterFuncHandlers[i].pxHandler(ucMBFrame, &usLength);
+							}
+						}
+						else {
+							eException = xMasterFuncHandlers[i].pxHandler(ucMBFrame, &usLength);
+						}
+						vMBMasterSetCBRunInMasterMode(FALSE);
+						break;
+					}
+				}
+			}
             /* If master has exception ,Master will send error process.Otherwise the Master is idle.*/
-            if (eException != MB_EX_NONE) ( void ) xMBMasterPortEventPost( EV_MASTER_ERROR_PROCESS );
-            else vMBMasterSetIsBusy( FALSE );
+            if (eException != MB_EX_NONE) {
+            	vMBMasterSetErrorType(EV_ERROR_EXECUTE_FUNCTION);
+            	( void ) xMBMasterPortEventPost( EV_MASTER_ERROR_PROCESS );
+            }
+            else {
+            	vMBMasterCBRequestScuuess( );
+            	vMBMasterRunResRelease( );
+            }
             break;
 
         case EV_MASTER_FRAME_SENT:
         	/* Master is busy now. */
-        	vMBMasterSetIsBusy( TRUE );
         	vMBMasterGetPDUSndBuf( &ucMBFrame );
-			eStatus = peMBMasterFrameSendCur( ucMBMasterGetDestAddress(), ucMBFrame, ucMBMasterGetPDUSndLength() );
+			eStatus = peMBMasterFrameSendCur( ucMBMasterGetDestAddress(), ucMBFrame, usMBMasterGetPDUSndLength() );
             break;
 
         case EV_MASTER_ERROR_PROCESS:
-        	vMBMasterSetIsBusy( FALSE );
+        	/* Execute specified error process callback function. */
+			errorType = eMBMasterGetErrorType();
+			vMBMasterGetPDUSndBuf( &ucMBFrame );
+			switch (errorType) {
+			case EV_ERROR_RESPOND_TIMEOUT:
+				vMBMasterErrorCBRespondTimeout(ucMBMasterGetDestAddress(),
+						ucMBFrame, usMBMasterGetPDUSndLength());
+				break;
+			case EV_ERROR_RECEIVE_DATA:
+				vMBMasterErrorCBReceiveData(ucMBMasterGetDestAddress(),
+						ucMBFrame, usMBMasterGetPDUSndLength());
+				break;
+			case EV_ERROR_EXECUTE_FUNCTION:
+				vMBMasterErrorCBExecuteFunction(ucMBMasterGetDestAddress(),
+						ucMBFrame, usMBMasterGetPDUSndLength());
+				break;
+			}
+			vMBMasterRunResRelease();
         	break;
         }
     }
     return MB_ENOERR;
 }
-/* Get whether the Modbus Master is busy.*/
-BOOL xMBMasterGetIsBusy( void )
-{
-	return xMasterIsBusy;
-}
-/* Set whether the Modbus Master is busy.*/
-void vMBMasterSetIsBusy( BOOL IsBusy )
-{
-	xMasterIsBusy = IsBusy;
-}
+
 /* Get whether the Modbus Master is run in master mode.*/
 BOOL xMBMasterGetCBRunInMasterMode( void )
 {
@@ -348,15 +380,27 @@ void vMBMasterSetCBRunInMasterMode( BOOL IsMasterMode )
 {
 	xMBRunInMasterMode = IsMasterMode;
 }
-/* Get Modbus Master send destination address*/
+/* Get Modbus Master send destination address. */
 UCHAR ucMBMasterGetDestAddress( void )
 {
 	return ucMBMasterDestAddress;
 }
-/* Set Modbus Master send destination address*/
+/* Set Modbus Master send destination address. */
 void vMBMasterSetDestAddress( UCHAR Address )
 {
 	ucMBMasterDestAddress = Address;
 }
+/* Get Modbus Master current error event type. */
+eMBMasterErrorEventType eMBMasterGetErrorType( void )
+{
+	return eMBMasterCurErrorType;
+}
+/* Set Modbus Master current error event type. */
+void vMBMasterSetErrorType( eMBMasterErrorEventType errorType )
+{
+	eMBMasterCurErrorType = errorType;
+}
+
+
 
 #endif
diff --git a/components/net/freemodbus-v1.6.0/modbus/rtu/mbcrc.c b/components/net/freemodbus/modbus/rtu/mbcrc.c
index 29b9ea765a..29b9ea765a 100644
--- a/components/net/freemodbus-v1.6.0/modbus/rtu/mbcrc.c
+++ b/components/net/freemodbus/modbus/rtu/mbcrc.c
diff --git a/components/net/freemodbus-v1.6.0/modbus/rtu/mbcrc.h b/components/net/freemodbus/modbus/rtu/mbcrc.h
index db227763f1..db227763f1 100644
--- a/components/net/freemodbus-v1.6.0/modbus/rtu/mbcrc.h
+++ b/components/net/freemodbus/modbus/rtu/mbcrc.h
diff --git a/components/net/freemodbus-v1.6.0/modbus/rtu/mbrtu.c b/components/net/freemodbus/modbus/rtu/mbrtu.c
index c023c92654..c023c92654 100644
--- a/components/net/freemodbus-v1.6.0/modbus/rtu/mbrtu.c
+++ b/components/net/freemodbus/modbus/rtu/mbrtu.c
diff --git a/components/net/freemodbus-v1.6.0/modbus/rtu/mbrtu.h b/components/net/freemodbus/modbus/rtu/mbrtu.h
index 98c43de4aa..98c43de4aa 100644
--- a/components/net/freemodbus-v1.6.0/modbus/rtu/mbrtu.h
+++ b/components/net/freemodbus/modbus/rtu/mbrtu.h
diff --git a/components/net/freemodbus-v1.6.0/modbus/rtu/mbrtu_m.c b/components/net/freemodbus/modbus/rtu/mbrtu_m.c
index fffbb23f9f..987c9a3156 100644
--- a/components/net/freemodbus-v1.6.0/modbus/rtu/mbrtu_m.c
+++ b/components/net/freemodbus/modbus/rtu/mbrtu_m.c
@@ -74,7 +74,7 @@ static volatile eMBMasterRcvState eRcvState;
 
 static volatile UCHAR  ucMasterRTUSndBuf[MB_PDU_SIZE_MAX];
 static volatile UCHAR  ucMasterRTURcvBuf[MB_SER_PDU_SIZE_MAX];
-static volatile UCHAR  ucMasterSendPDULength;
+static volatile USHORT usMasterSendPDULength;
 
 static volatile UCHAR *pucMasterSndBufferCur;
 static volatile USHORT usMasterSndBufferCount;
@@ -235,7 +235,7 @@ xMBMasterRTUReceiveFSM( void )
     BOOL            xTaskNeedSwitch = FALSE;
     UCHAR           ucByte;
 
-    assert_param( eSndState == STATE_M_TX_IDLE );
+    assert_param(( eSndState == STATE_M_TX_IDLE ) || ( eSndState == STATE_M_TX_XFWR ));
 
     /* Always read the character. */
     ( void )xMBMasterPortSerialGetByte( ( CHAR * ) & ucByte );
@@ -364,12 +364,15 @@ xMBMasterRTUTimerExpired(void)
 
 		/* An error occured while receiving the frame. */
 	case STATE_M_RX_ERROR:
+		vMBMasterSetErrorType(EV_ERROR_RECEIVE_DATA);
+		xNeedPoll = xMBMasterPortEventPost( EV_MASTER_ERROR_PROCESS );
 		break;
 
 		/* Function called in an illegal state. */
 	default:
 		assert_param(
-				( eRcvState == STATE_M_RX_INIT ) || ( eRcvState == STATE_M_RX_RCV ) || ( eRcvState == STATE_M_RX_ERROR ));
+				( eRcvState == STATE_M_RX_INIT ) || ( eRcvState == STATE_M_RX_RCV ) ||
+				( eRcvState == STATE_M_RX_ERROR ) || ( eRcvState == STATE_M_RX_IDLE ));
 		break;
 	}
 	eRcvState = STATE_M_RX_IDLE;
@@ -380,18 +383,24 @@ xMBMasterRTUTimerExpired(void)
 		 * If the frame is broadcast,The master will idle,and if the frame is not
 		 * broadcast.Notify the listener process error.*/
 	case STATE_M_TX_XFWR:
-		if ( xFrameIsBroadcast == FALSE ) xNeedPoll = xMBMasterPortEventPost(EV_MASTER_ERROR_PROCESS);
+		if ( xFrameIsBroadcast == FALSE ) {
+			vMBMasterSetErrorType(EV_ERROR_RESPOND_TIMEOUT);
+			xNeedPoll = xMBMasterPortEventPost(EV_MASTER_ERROR_PROCESS);
+		}
 		break;
 		/* Function called in an illegal state. */
 	default:
-		assert_param( eSndState == STATE_M_TX_XFWR );
+		assert_param(
+				( eSndState == STATE_M_TX_XFWR ) || ( eSndState == STATE_M_TX_IDLE ));
 		break;
 	}
 	eSndState = STATE_M_TX_IDLE;
 
 	vMBMasterPortTimersDisable( );
-	/* If timer mode is convert delay ,then Master is idel now. */
-	if (eMasterCurTimerMode == MB_TMODE_CONVERT_DELAY) vMBMasterSetIsBusy( FALSE );
+	/* If timer mode is convert delay, the master event then turns EV_MASTER_EXECUTE status. */
+	if (eMasterCurTimerMode == MB_TMODE_CONVERT_DELAY) {
+		xNeedPoll = xMBMasterPortEventPost( EV_MASTER_EXECUTE );
+	}
 
 	return xNeedPoll;
 }
@@ -409,15 +418,15 @@ void vMBMasterGetPDUSndBuf( UCHAR ** pucFrame )
 }
 
 /* Set Modbus Master send PDU's buffer length.*/
-void vMBMasterSetPDUSndLength( UCHAR SendPDULength )
+void vMBMasterSetPDUSndLength( USHORT SendPDULength )
 {
-	ucMasterSendPDULength = SendPDULength;
+	usMasterSendPDULength = SendPDULength;
 }
 
 /* Get Modbus Master send PDU's buffer length.*/
-UCHAR ucMBMasterGetPDUSndLength( void )
+USHORT usMBMasterGetPDUSndLength( void )
 {
-	return ucMasterSendPDULength;
+	return usMasterSendPDULength;
 }
 
 /* Set Modbus Master current timer mode.*/
@@ -425,5 +434,10 @@ void vMBMasterSetCurTimerMode( eMBMasterTimerMode eMBTimerMode )
 {
 	eMasterCurTimerMode = eMBTimerMode;
 }
+
+/* The master request is broadcast? */
+BOOL xMBMasterRequestIsBroadcast( void ){
+	return xFrameIsBroadcast;
+}
 #endif
 
diff --git a/components/net/freemodbus-v1.6.0/modbus/tcp/mbtcp.c b/components/net/freemodbus/modbus/tcp/mbtcp.c
index 3eb3b7071f..3eb3b7071f 100644
--- a/components/net/freemodbus-v1.6.0/modbus/tcp/mbtcp.c
+++ b/components/net/freemodbus/modbus/tcp/mbtcp.c
diff --git a/components/net/freemodbus-v1.6.0/modbus/tcp/mbtcp.h b/components/net/freemodbus/modbus/tcp/mbtcp.h
index 905d113c5a..905d113c5a 100644
--- a/components/net/freemodbus-v1.6.0/modbus/tcp/mbtcp.h
+++ b/components/net/freemodbus/modbus/tcp/mbtcp.h
diff --git a/components/net/freemodbus-v1.6.0/port/port.c b/components/net/freemodbus/port/port.c
index 459481cc1d..d01c5c9d6a 100644
--- a/components/net/freemodbus-v1.6.0/port/port.c
+++ b/components/net/freemodbus/port/port.c
@@ -1,6 +1,6 @@
  /*
-  * FreeModbus Libary: LPC214X Port
-  * Copyright (C) 2007 Tiago Prado Lone <[email protected]>
+  * FreeModbus Libary: RT-Thread Port
+  * Copyright (C) 2013 Armink <[email protected]>
   *
   * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
@@ -16,7 +16,7 @@
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
   *
-  * File: $Id: port.c,v 1.1 2007/04/24 23:15:18 wolti Exp $
+  * File: $Id: port.c,v 1.60 2015/02/01 9:18:05 Armink $
   */
 
 /* ----------------------- System includes --------------------------------*/
@@ -24,16 +24,15 @@
 /* ----------------------- Modbus includes ----------------------------------*/
 #include "port.h"
 /* ----------------------- Variables ----------------------------------------*/
-
+static rt_base_t level;
 /* ----------------------- Start implementation -----------------------------*/
 void EnterCriticalSection(void)
 {
-	//�ر�ȫ���ж�
-	__disable_irq();
+    level = rt_hw_interrupt_disable();
 }
 
 void ExitCriticalSection(void)
 {
-	//����ȫ���ж�
-	__enable_irq();
+    rt_hw_interrupt_enable(level);
 }
+
diff --git a/components/net/freemodbus-v1.6.0/port/port.h b/components/net/freemodbus/port/port.h
index c79df3d887..73d2177c9a 100644
--- a/components/net/freemodbus-v1.6.0/port/port.h
+++ b/components/net/freemodbus/port/port.h
@@ -1,6 +1,6 @@
 /*
  * FreeModbus Libary: BARE Port
- * Copyright (C) 2006 Christian Walter <[email protected]>
+ * Copyright (C) 2013 Armink <[email protected]>
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -30,22 +30,13 @@
 #include <assert.h>
 #include <inttypes.h>
 
-#define	INLINE
+#define INLINE
 #define PR_BEGIN_EXTERN_C           extern "C" {
-#define	PR_END_EXTERN_C             }
+#define PR_END_EXTERN_C             }
 
-//TODO  ��ʱ��дB13���ţ�����������ʱ��ȷ��
-#define SLAVE_RS485_SEND_MODE  GPIO_SetBits(GPIOB,GPIO_Pin_13)
-#define SLAVE_RS485_RECEIVE_MODE  GPIO_ResetBits(GPIOB,GPIO_Pin_13)
-#define MASTER_RS485_SEND_MODE  GPIO_SetBits(GPIOB,GPIO_Pin_13)
-#define MASTER_RS485_RECEIVE_MODE  GPIO_ResetBits(GPIOB,GPIO_Pin_13)
-
-#define ENTER_CRITICAL_SECTION()	EnterCriticalSection()
+#define ENTER_CRITICAL_SECTION()    EnterCriticalSection()
 #define EXIT_CRITICAL_SECTION()    ExitCriticalSection()
 
-void EnterCriticalSection(void);
-void ExitCriticalSection(void);
-
 typedef uint8_t BOOL;
 
 typedef unsigned char UCHAR;
@@ -65,4 +56,7 @@ typedef int32_t LONG;
 #define FALSE           0
 #endif
 
+void EnterCriticalSection(void);
+void ExitCriticalSection(void);
+
 #endif
diff --git a/components/net/freemodbus-v1.6.0/port/portevent.c b/components/net/freemodbus/port/portevent.c
index 86c7b5e7a5..1a881166be 100644
--- a/components/net/freemodbus-v1.6.0/port/portevent.c
+++ b/components/net/freemodbus/port/portevent.c
@@ -1,5 +1,5 @@
 /*
- * FreeModbus Libary: STM32 Port
+ * FreeModbus Libary: RT-Thread Port
  * Copyright (C) 2013 Armink <[email protected]>
  *
  * This library is free software; you can redistribute it and/or
@@ -24,35 +24,45 @@
 #include "mbport.h"
 
 /* ----------------------- Variables ----------------------------------------*/
-static eMBEventType eQueuedEvent;
-static BOOL     xEventInQueue;
-
+static struct rt_event     xSlaveOsEvent;
 /* ----------------------- Start implementation -----------------------------*/
 BOOL
 xMBPortEventInit( void )
 {
-    xEventInQueue = FALSE;
+    rt_event_init(&xSlaveOsEvent,"slave event",RT_IPC_FLAG_PRIO);
     return TRUE;
 }
 
 BOOL
 xMBPortEventPost( eMBEventType eEvent )
 {
-    xEventInQueue = TRUE;
-    eQueuedEvent = eEvent;
+    rt_event_send(&xSlaveOsEvent, eEvent);
     return TRUE;
 }
 
 BOOL
 xMBPortEventGet( eMBEventType * eEvent )
 {
-    BOOL            xEventHappened = FALSE;
-
-    if( xEventInQueue )
+    rt_uint32_t recvedEvent;
+    /* waiting forever OS event */
+    rt_event_recv(&xSlaveOsEvent,
+            EV_READY | EV_FRAME_RECEIVED | EV_EXECUTE | EV_FRAME_SENT,
+            RT_EVENT_FLAG_OR | RT_EVENT_FLAG_CLEAR, RT_WAITING_FOREVER,
+            &recvedEvent);
+    switch (recvedEvent)
     {
-        *eEvent = eQueuedEvent;
-        xEventInQueue = FALSE;
-        xEventHappened = TRUE;
+    case EV_READY:
+        *eEvent = EV_READY;
+        break;
+    case EV_FRAME_RECEIVED:
+        *eEvent = EV_FRAME_RECEIVED;
+        break;
+    case EV_EXECUTE:
+        *eEvent = EV_EXECUTE;
+        break;
+    case EV_FRAME_SENT:
+        *eEvent = EV_FRAME_SENT;
+        break;
     }
-    return xEventHappened;
+    return TRUE;
 }
diff --git a/components/net/freemodbus/port/portevent_m.c b/components/net/freemodbus/port/portevent_m.c
new file mode 100644
index 0000000000..031a3b84ef
--- /dev/null
+++ b/components/net/freemodbus/port/portevent_m.c
@@ -0,0 +1,239 @@
+/*
+ * FreeModbus Libary: RT-Thread Port
+ * Copyright (C) 2013 Armink <[email protected]>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * File: $Id: portevent_m.c v 1.60 2013/08/13 15:07:05 Armink add Master Functions$
+ */
+
+/* ----------------------- Modbus includes ----------------------------------*/
+#include "mb.h"
+#include "mb_m.h"
+#include "mbport.h"
+#include "port.h"
+
+#if MB_MASTER_RTU_ENABLED > 0 || MB_MASTER_ASCII_ENABLED > 0
+/* ----------------------- Defines ------------------------------------------*/
+/* ----------------------- Variables ----------------------------------------*/
+static struct rt_semaphore xMasterRunRes;
+static struct rt_event     xMasterOsEvent;
+/* ----------------------- Start implementation -----------------------------*/
+BOOL
+xMBMasterPortEventInit( void )
+{
+    rt_event_init(&xMasterOsEvent,"master event",RT_IPC_FLAG_PRIO);
+    return TRUE;
+}
+
+BOOL
+xMBMasterPortEventPost( eMBMasterEventType eEvent )
+{
+    rt_event_send(&xMasterOsEvent, eEvent);
+    return TRUE;
+}
+
+BOOL
+xMBMasterPortEventGet( eMBMasterEventType * eEvent )
+{
+    rt_uint32_t recvedEvent;
+    /* waiting forever OS event */
+    rt_event_recv(&xMasterOsEvent,
+            EV_MASTER_READY | EV_MASTER_FRAME_RECEIVED | EV_MASTER_EXECUTE |
+            EV_MASTER_FRAME_SENT | EV_MASTER_ERROR_PROCESS,
+            RT_EVENT_FLAG_OR | RT_EVENT_FLAG_CLEAR, RT_WAITING_FOREVER,
+            &recvedEvent);
+    /* the enum type couldn't convert to int type */
+    switch (recvedEvent)
+    {
+    case EV_MASTER_READY:
+        *eEvent = EV_MASTER_READY;
+        break;
+    case EV_MASTER_FRAME_RECEIVED:
+        *eEvent = EV_MASTER_FRAME_RECEIVED;
+        break;
+    case EV_MASTER_EXECUTE:
+        *eEvent = EV_MASTER_EXECUTE;
+        break;
+    case EV_MASTER_FRAME_SENT:
+        *eEvent = EV_MASTER_FRAME_SENT;
+        break;
+    case EV_MASTER_ERROR_PROCESS:
+        *eEvent = EV_MASTER_ERROR_PROCESS;
+        break;
+    }
+    return TRUE;
+}
+/**
+ * This function is initialize the OS resource for modbus master.
+ * Note:The resource is define by OS.If you not use OS this function can be empty.
+ *
+ */
+void vMBMasterOsResInit( void )
+{
+    rt_sem_init(&xMasterRunRes, "master res", 0x01 , RT_IPC_FLAG_PRIO);
+}
+
+/**
+ * This function is take Mobus Master running resource.
+ * Note:The resource is define by Operating System.If you not use OS this function can be just return TRUE.
+ *
+ * @param lTimeOut the waiting time.
+ *
+ * @return resource taked result
+ */
+BOOL xMBMasterRunResTake( LONG lTimeOut )
+{
+    /*If waiting time is -1 .It will wait forever */
+    return rt_sem_take(&xMasterRunRes, lTimeOut) ? FALSE : TRUE ;
+}
+
+/**
+ * This function is release Mobus Master running resource.
+ * Note:The resource is define by Operating System.If you not use OS this function can be empty.
+ *
+ */
+void vMBMasterRunResRelease( void )
+{
+    /* release resource */
+    rt_sem_release(&xMasterRunRes);
+}
+
+/**
+ * This is modbus master respond timeout error process callback function.
+ * @note There functions will block modbus master poll while execute OS waiting.
+ * So,for real-time of system.Do not execute too much waiting process.
+ *
+ * @param ucDestAddress destination salve address
+ * @param pucPDUData PDU buffer data
+ * @param ucPDULength PDU buffer length
+ *
+ */
+void vMBMasterErrorCBRespondTimeout(UCHAR ucDestAddress, const UCHAR* pucPDUData,
+        USHORT ucPDULength) {
+    /**
+     * @note This code is use OS's event mechanism for modbus master protocol stack.
+     * If you don't use OS, you can change it.
+     */
+    rt_event_send(&xMasterOsEvent, EV_MASTER_ERROR_RESPOND_TIMEOUT);
+
+    /* You can add your code under here. */
+
+}
+
+/**
+ * This is modbus master receive data error process callback function.
+ * @note There functions will block modbus master poll while execute OS waiting.
+ * So,for real-time of system.Do not execute too much waiting process.
+ *
+ * @param ucDestAddress destination salve address
+ * @param pucPDUData PDU buffer data
+ * @param ucPDULength PDU buffer length
+ *
+ */
+void vMBMasterErrorCBReceiveData(UCHAR ucDestAddress, const UCHAR* pucPDUData,
+        USHORT ucPDULength) {
+    /**
+     * @note This code is use OS's event mechanism for modbus master protocol stack.
+     * If you don't use OS, you can change it.
+     */
+    rt_event_send(&xMasterOsEvent, EV_MASTER_ERROR_RECEIVE_DATA);
+
+    /* You can add your code under here. */
+
+}
+
+/**
+ * This is modbus master execute function error process callback function.
+ * @note There functions will block modbus master poll while execute OS waiting.
+ * So,for real-time of system.Do not execute too much waiting process.
+ *
+ * @param ucDestAddress destination salve address
+ * @param pucPDUData PDU buffer data
+ * @param ucPDULength PDU buffer length
+ *
+ */
+void vMBMasterErrorCBExecuteFunction(UCHAR ucDestAddress, const UCHAR* pucPDUData,
+        USHORT ucPDULength) {
+    /**
+     * @note This code is use OS's event mechanism for modbus master protocol stack.
+     * If you don't use OS, you can change it.
+     */
+    rt_event_send(&xMasterOsEvent, EV_MASTER_ERROR_EXECUTE_FUNCTION);
+
+    /* You can add your code under here. */
+
+}
+
+/**
+ * This is modbus master request process success callback function.
+ * @note There functions will block modbus master poll while execute OS waiting.
+ * So,for real-time of system.Do not execute too much waiting process.
+ *
+ */
+void vMBMasterCBRequestScuuess( void ) {
+    /**
+     * @note This code is use OS's event mechanism for modbus master protocol stack.
+     * If you don't use OS, you can change it.
+     */
+    rt_event_send(&xMasterOsEvent, EV_MASTER_PROCESS_SUCESS);
+
+    /* You can add your code under here. */
+
+}
+
+/**
+ * This function is wait for modbus master request finish and return result.
+ * Waiting result include request process success, request respond timeout,
+ * receive data error and execute function error.You can use the above callback function.
+ * @note If you are use OS, you can use OS's event mechanism. Otherwise you have to run
+ * much user custom delay for waiting.
+ *
+ * @return request error code
+ */
+eMBMasterReqErrCode eMBMasterWaitRequestFinish( void ) {
+    eMBMasterReqErrCode    eErrStatus = MB_MRE_NO_ERR;
+    rt_uint32_t recvedEvent;
+    /* waiting for OS event */
+    rt_event_recv(&xMasterOsEvent,
+            EV_MASTER_PROCESS_SUCESS | EV_MASTER_ERROR_RESPOND_TIMEOUT
+                    | EV_MASTER_ERROR_RECEIVE_DATA
+                    | EV_MASTER_ERROR_EXECUTE_FUNCTION,
+            RT_EVENT_FLAG_OR | RT_EVENT_FLAG_CLEAR, RT_WAITING_FOREVER,
+            &recvedEvent);
+    switch (recvedEvent)
+    {
+    case EV_MASTER_PROCESS_SUCESS:
+        break;
+    case EV_MASTER_ERROR_RESPOND_TIMEOUT:
+    {
+        eErrStatus = MB_MRE_TIMEDOUT;
+        break;
+    }
+    case EV_MASTER_ERROR_RECEIVE_DATA:
+    {
+        eErrStatus = MB_MRE_REV_DATA;
+        break;
+    }
+    case EV_MASTER_ERROR_EXECUTE_FUNCTION:
+    {
+        eErrStatus = MB_MRE_EXE_FUN;
+        break;
+    }
+    }
+    return eErrStatus;
+}
+
+#endif
diff --git a/components/net/freemodbus/port/portserial.c b/components/net/freemodbus/port/portserial.c
new file mode 100644
index 0000000000..317c7f4605
--- /dev/null
+++ b/components/net/freemodbus/port/portserial.c
@@ -0,0 +1,222 @@
+/*
+ * FreeModbus Libary: RT-Thread Port
+ * Copyright (C) 2013 Armink <[email protected]>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * File: $Id: portserial.c,v 1.60 2013/08/13 15:07:05 Armink $
+ */
+
+#include "port.h"
+
+/* ----------------------- Modbus includes ----------------------------------*/
+#include "mb.h"
+#include "mbport.h"
+#include "rtdevice.h"
+#include "board.h"
+
+/* ----------------------- Static variables ---------------------------------*/
+ALIGN(RT_ALIGN_SIZE)
+/* software simulation serial transmit IRQ handler thread stack */
+static rt_uint8_t serial_soft_trans_irq_stack[512];
+/* software simulation serial transmit IRQ handler thread */
+static struct rt_thread thread_serial_soft_trans_irq;
+/* serial event */
+static struct rt_event event_serial;
+/* modbus slave serial device */
+static rt_serial_t *serial;
+
+/* ----------------------- Defines ------------------------------------------*/
+/* serial transmit event */
+#define EVENT_SERIAL_TRANS_START    (1<<0)
+
+/* ----------------------- static functions ---------------------------------*/
+static void prvvUARTTxReadyISR(void);
+static void prvvUARTRxISR(void);
+static rt_err_t serial_rx_ind(rt_device_t dev, rt_size_t size);
+static void serial_soft_trans_irq(void* parameter);
+
+/* ----------------------- Start implementation -----------------------------*/
+BOOL xMBPortSerialInit(UCHAR ucPORT, ULONG ulBaudRate, UCHAR ucDataBits,
+        eMBParity eParity)
+{
+    /**
+     * set 485 mode receive and transmit control IO
+     * @note MODBUS_SLAVE_RT_CONTROL_PIN_INDEX need be defined by user
+     */
+    rt_pin_mode(MODBUS_SLAVE_RT_CONTROL_PIN_INDEX, PIN_MODE_OUTPUT);
+
+    /* set serial name */
+    if (ucPORT == 1) {
+#if defined(RT_USING_UART1) || defined(RT_USING_REMAP_UART1)
+        extern struct rt_serial_device serial1;
+        serial = &serial1;
+#endif
+    } else if (ucPORT == 2) {
+#if defined(RT_USING_UART2)
+        extern struct rt_serial_device serial2;
+        serial = &serial2;
+#endif
+    } else if (ucPORT == 3) {
+#if defined(RT_USING_UART3)
+        extern struct rt_serial_device serial3;
+        serial = &serial3;
+#endif
+    }
+    /* set serial configure parameter */
+    serial->config.baud_rate = ulBaudRate;
+    serial->config.stop_bits = STOP_BITS_1;
+    switch(eParity){
+    case MB_PAR_NONE: {
+        serial->config.data_bits = DATA_BITS_8;
+        serial->config.parity = PARITY_NONE;
+        break;
+    }
+    case MB_PAR_ODD: {
+        serial->config.data_bits = DATA_BITS_9;
+        serial->config.parity = PARITY_ODD;
+        break;
+    }
+    case MB_PAR_EVEN: {
+        serial->config.data_bits = DATA_BITS_9;
+        serial->config.parity = PARITY_EVEN;
+        break;
+    }
+    }
+    /* set serial configure */
+    serial->ops->configure(serial, &(serial->config));
+
+    /* open serial device */
+    if (!serial->parent.open(&serial->parent,
+            RT_DEVICE_OFLAG_RDWR | RT_DEVICE_FLAG_INT_RX )) {
+        serial->parent.rx_indicate = serial_rx_ind;
+    } else {
+        return FALSE;
+    }
+
+    /* software initialize */
+    rt_thread_init(&thread_serial_soft_trans_irq,
+                   "slave trans",
+                   serial_soft_trans_irq,
+                   RT_NULL,
+                   serial_soft_trans_irq_stack,
+                   sizeof(serial_soft_trans_irq_stack),
+                   10, 5);
+    rt_thread_startup(&thread_serial_soft_trans_irq);
+    rt_event_init(&event_serial, "slave event", RT_IPC_FLAG_PRIO);
+
+    return TRUE;
+}
+
+void vMBPortSerialEnable(BOOL xRxEnable, BOOL xTxEnable)
+{
+    rt_uint32_t recved_event;
+    if (xRxEnable)
+    {
+        /* enable RX interrupt */
+        serial->ops->control(serial, RT_DEVICE_CTRL_SET_INT, (void *)RT_DEVICE_FLAG_INT_RX);
+        /* switch 485 to receive mode */
+        rt_pin_write(MODBUS_SLAVE_RT_CONTROL_PIN_INDEX, PIN_LOW);
+    }
+    else
+    {
+        /* switch 485 to transmit mode */
+        rt_pin_write(MODBUS_SLAVE_RT_CONTROL_PIN_INDEX, PIN_HIGH);
+        /* disable RX interrupt */
+        serial->ops->control(serial, RT_DEVICE_CTRL_CLR_INT, (void *)RT_DEVICE_FLAG_INT_RX);
+    }
+    if (xTxEnable)
+    {
+        /* start serial transmit */
+        rt_event_send(&event_serial, EVENT_SERIAL_TRANS_START);
+    }
+    else
+    {
+        /* stop serial transmit */
+        rt_event_recv(&event_serial, EVENT_SERIAL_TRANS_START,
+                RT_EVENT_FLAG_OR | RT_EVENT_FLAG_CLEAR, 0,
+                &recved_event);
+    }
+}
+
+void vMBPortClose(void)
+{
+    serial->parent.close(&(serial->parent));
+}
+
+BOOL xMBPortSerialPutByte(CHAR ucByte)
+{
+    serial->parent.write(&(serial->parent), 0, &ucByte, 1);
+    return TRUE;
+}
+
+BOOL xMBPortSerialGetByte(CHAR * pucByte)
+{
+    serial->parent.read(&(serial->parent), 0, pucByte, 1);
+    return TRUE;
+}
+
+/* 
+ * Create an interrupt handler for the transmit buffer empty interrupt
+ * (or an equivalent) for your target processor. This function should then
+ * call pxMBFrameCBTransmitterEmpty( ) which tells the protocol stack that
+ * a new character can be sent. The protocol stack will then call 
+ * xMBPortSerialPutByte( ) to send the character.
+ */
+void prvvUARTTxReadyISR(void)
+{
+    pxMBFrameCBTransmitterEmpty();
+}
+
+/* 
+ * Create an interrupt handler for the receive interrupt for your target
+ * processor. This function should then call pxMBFrameCBByteReceived( ). The
+ * protocol stack will then call xMBPortSerialGetByte( ) to retrieve the
+ * character.
+ */
+void prvvUARTRxISR(void)
+{
+    pxMBFrameCBByteReceived();
+}
+
+/**
+ * Software simulation serial transmit IRQ handler.
+ *
+ * @param parameter parameter
+ */
+static void serial_soft_trans_irq(void* parameter) {
+    rt_uint32_t recved_event;
+    while (1)
+    {
+        /* waiting for serial transmit start */
+        rt_event_recv(&event_serial, EVENT_SERIAL_TRANS_START, RT_EVENT_FLAG_OR,
+                RT_WAITING_FOREVER, &recved_event);
+        /* execute modbus callback */
+        prvvUARTTxReadyISR();
+    }
+}
+
+/**
+ * This function is serial receive callback function
+ *
+ * @param dev the device of serial
+ * @param size the data size that receive
+ *
+ * @return return RT_EOK
+ */
+static rt_err_t serial_rx_ind(rt_device_t dev, rt_size_t size) {
+    prvvUARTRxISR();
+    return RT_EOK;
+}
diff --git a/components/net/freemodbus/port/portserial_m.c b/components/net/freemodbus/port/portserial_m.c
new file mode 100644
index 0000000000..8ec0d081f1
--- /dev/null
+++ b/components/net/freemodbus/port/portserial_m.c
@@ -0,0 +1,225 @@
+/*
+ * FreeModbus Libary: RT-Thread Port
+ * Copyright (C) 2013 Armink <[email protected]>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * File: $Id: portserial_m.c,v 1.60 2013/08/13 15:07:05 Armink add Master Functions $
+ */
+
+#include "port.h"
+
+/* ----------------------- Modbus includes ----------------------------------*/
+#include "mb.h"
+#include "mbport.h"
+#include "rtdevice.h"
+#include "board.h"
+
+#if MB_MASTER_RTU_ENABLED > 0 || MB_MASTER_ASCII_ENABLED > 0
+/* ----------------------- Static variables ---------------------------------*/
+ALIGN(RT_ALIGN_SIZE)
+/* software simulation serial transmit IRQ handler thread stack */
+static rt_uint8_t serial_soft_trans_irq_stack[512];
+/* software simulation serial transmit IRQ handler thread */
+static struct rt_thread thread_serial_soft_trans_irq;
+/* serial event */
+static struct rt_event event_serial;
+/* modbus slave serial device */
+static rt_serial_t *serial;
+
+/* ----------------------- Defines ------------------------------------------*/
+/* serial transmit event */
+#define EVENT_SERIAL_TRANS_START    (1<<0)
+
+/* ----------------------- static functions ---------------------------------*/
+static void prvvUARTTxReadyISR(void);
+static void prvvUARTRxISR(void);
+static rt_err_t serial_rx_ind(rt_device_t dev, rt_size_t size);
+static void serial_soft_trans_irq(void* parameter);
+
+/* ----------------------- Start implementation -----------------------------*/
+BOOL xMBMasterPortSerialInit(UCHAR ucPORT, ULONG ulBaudRate, UCHAR ucDataBits,
+        eMBParity eParity)
+{
+    /**
+     * set 485 mode receive and transmit control IO
+     * @note MODBUS_MASTER_RT_CONTROL_PIN_INDEX need be defined by user
+     */
+    rt_pin_mode(MODBUS_MASTER_RT_CONTROL_PIN_INDEX, PIN_MODE_OUTPUT);
+
+    /* set serial name */
+    if (ucPORT == 1) {
+#if defined(RT_USING_UART1) || defined(RT_USING_REMAP_UART1)
+        extern struct rt_serial_device serial1;
+        serial = &serial1;
+#endif
+    } else if (ucPORT == 2) {
+#if defined(RT_USING_UART2)
+        extern struct rt_serial_device serial2;
+        serial = &serial2;
+#endif
+    } else if (ucPORT == 3) {
+#if defined(RT_USING_UART3)
+        extern struct rt_serial_device serial3;
+        serial = &serial3;
+#endif
+    }
+    /* set serial configure parameter */
+    serial->config.baud_rate = ulBaudRate;
+    serial->config.stop_bits = STOP_BITS_1;
+    switch(eParity){
+    case MB_PAR_NONE: {
+        serial->config.data_bits = DATA_BITS_8;
+        serial->config.parity = PARITY_NONE;
+        break;
+    }
+    case MB_PAR_ODD: {
+        serial->config.data_bits = DATA_BITS_9;
+        serial->config.parity = PARITY_ODD;
+        break;
+    }
+    case MB_PAR_EVEN: {
+        serial->config.data_bits = DATA_BITS_9;
+        serial->config.parity = PARITY_EVEN;
+        break;
+    }
+    }
+    /* set serial configure */
+    serial->ops->configure(serial, &(serial->config));
+
+    /* open serial device */
+    if (!serial->parent.open(&serial->parent,
+            RT_DEVICE_OFLAG_RDWR | RT_DEVICE_FLAG_INT_RX )) {
+        serial->parent.rx_indicate = serial_rx_ind;
+    } else {
+        return FALSE;
+    }
+
+    /* software initialize */
+    rt_thread_init(&thread_serial_soft_trans_irq,
+                   "slave trans",
+                   serial_soft_trans_irq,
+                   RT_NULL,
+                   serial_soft_trans_irq_stack,
+                   sizeof(serial_soft_trans_irq_stack),
+                   10, 5);
+    rt_thread_startup(&thread_serial_soft_trans_irq);
+    rt_event_init(&event_serial, "slave event", RT_IPC_FLAG_PRIO);
+
+    return TRUE;
+}
+
+void vMBMasterPortSerialEnable(BOOL xRxEnable, BOOL xTxEnable)
+{
+    rt_uint32_t recved_event;
+    if (xRxEnable)
+    {
+        /* enable RX interrupt */
+        serial->ops->control(serial, RT_DEVICE_CTRL_SET_INT, (void *)RT_DEVICE_FLAG_INT_RX);
+        /* switch 485 to receive mode */
+        rt_pin_write(MODBUS_MASTER_RT_CONTROL_PIN_INDEX, PIN_LOW);
+    }
+    else
+    {
+        /* switch 485 to transmit mode */
+        rt_pin_write(MODBUS_MASTER_RT_CONTROL_PIN_INDEX, PIN_HIGH);
+        /* disable RX interrupt */
+        serial->ops->control(serial, RT_DEVICE_CTRL_CLR_INT, (void *)RT_DEVICE_FLAG_INT_RX);
+    }
+    if (xTxEnable)
+    {
+        /* start serial transmit */
+        rt_event_send(&event_serial, EVENT_SERIAL_TRANS_START);
+    }
+    else
+    {
+        /* stop serial transmit */
+        rt_event_recv(&event_serial, EVENT_SERIAL_TRANS_START,
+                RT_EVENT_FLAG_OR | RT_EVENT_FLAG_CLEAR, 0,
+                &recved_event);
+    }
+}
+
+void vMBMasterPortClose(void)
+{
+    serial->parent.close(&(serial->parent));
+}
+
+BOOL xMBMasterPortSerialPutByte(CHAR ucByte)
+{
+    serial->parent.write(&(serial->parent), 0, &ucByte, 1);
+    return TRUE;
+}
+
+BOOL xMBMasterPortSerialGetByte(CHAR * pucByte)
+{
+    serial->parent.read(&(serial->parent), 0, pucByte, 1);
+    return TRUE;
+}
+
+/* 
+ * Create an interrupt handler for the transmit buffer empty interrupt
+ * (or an equivalent) for your target processor. This function should then
+ * call pxMBFrameCBTransmitterEmpty( ) which tells the protocol stack that
+ * a new character can be sent. The protocol stack will then call 
+ * xMBPortSerialPutByte( ) to send the character.
+ */
+void prvvUARTTxReadyISR(void)
+{
+    pxMBMasterFrameCBTransmitterEmpty();
+}
+
+/* 
+ * Create an interrupt handler for the receive interrupt for your target
+ * processor. This function should then call pxMBFrameCBByteReceived( ). The
+ * protocol stack will then call xMBPortSerialGetByte( ) to retrieve the
+ * character.
+ */
+void prvvUARTRxISR(void)
+{
+    pxMBMasterFrameCBByteReceived();
+}
+
+/**
+ * Software simulation serial transmit IRQ handler.
+ *
+ * @param parameter parameter
+ */
+static void serial_soft_trans_irq(void* parameter) {
+    rt_uint32_t recved_event;
+    while (1)
+    {
+        /* waiting for serial transmit start */
+        rt_event_recv(&event_serial, EVENT_SERIAL_TRANS_START, RT_EVENT_FLAG_OR,
+                RT_WAITING_FOREVER, &recved_event);
+        /* execute modbus callback */
+        prvvUARTTxReadyISR();
+    }
+}
+
+/**
+ * This function is serial receive callback function
+ *
+ * @param dev the device of serial
+ * @param size the data size that receive
+ *
+ * @return return RT_EOK
+ */
+static rt_err_t serial_rx_ind(rt_device_t dev, rt_size_t size) {
+    prvvUARTRxISR();
+    return RT_EOK;
+}
+
+#endif
diff --git a/components/net/freemodbus-v1.6.0/port/portevent_m.c b/components/net/freemodbus/port/porttimer.c
index c78b6cbcb2..6f017d8759 100644
--- a/components/net/freemodbus-v1.6.0/port/portevent_m.c
+++ b/components/net/freemodbus/port/porttimer.c
@@ -1,5 +1,5 @@
 /*
- * FreeModbus Libary: STM32 Port
+ * FreeModbus Libary: RT-Thread Port
  * Copyright (C) 2013 Armink <[email protected]>
  *
  * This library is free software; you can redistribute it and/or
@@ -16,46 +16,48 @@
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  *
- * File: $Id: portevent_m.c v 1.60 2013/08/13 15:07:05 Armink add Master Functions$
+ * File: $Id: porttimer.c,v 1.60 2013/08/13 15:07:05 Armink $
  */
 
+/* ----------------------- Platform includes --------------------------------*/
+#include "port.h"
+
 /* ----------------------- Modbus includes ----------------------------------*/
 #include "mb.h"
 #include "mbport.h"
 
-#if MB_MASTER_RTU_ENABLED > 0 || MB_MASTER_ASCII_ENABLED
-/* ----------------------- Variables ----------------------------------------*/
-static eMBMasterEventType eMasterQueuedEvent;
-static BOOL     xMasterEventInQueue;
+/* ----------------------- static functions ---------------------------------*/
+static struct rt_timer timer;
+static void prvvTIMERExpiredISR(void);
+static void timer_timeout_ind(void* parameter);
 
 /* ----------------------- Start implementation -----------------------------*/
-BOOL
-xMBMasterPortEventInit( void )
+BOOL xMBPortTimersInit(USHORT usTim1Timerout50us)
 {
-    xMasterEventInQueue = FALSE;
+    rt_timer_init(&timer, "slave timer",
+                   timer_timeout_ind, /* bind timeout callback function */
+                   RT_NULL,
+                   (50*usTim1Timerout50us)/(1000*1000/RT_TICK_PER_SECOND),
+                   RT_TIMER_FLAG_ONE_SHOT); /* one shot */
     return TRUE;
 }
 
-BOOL
-xMBMasterPortEventPost( eMBMasterEventType eEvent )
+void vMBPortTimersEnable()
 {
-    xMasterEventInQueue = TRUE;
-    eMasterQueuedEvent = eEvent;
-    return TRUE;
+    rt_timer_start(&timer);
 }
 
-BOOL
-xMBMasterPortEventGet( eMBMasterEventType * eEvent )
+void vMBPortTimersDisable()
 {
-    BOOL            xEventHappened = FALSE;
+    rt_timer_stop(&timer);
+}
 
-    if( xMasterEventInQueue )
-    {
-        *eEvent = eMasterQueuedEvent;
-        xMasterEventInQueue = FALSE;
-        xEventHappened = TRUE;
-    }
-    return xEventHappened;
+void prvvTIMERExpiredISR(void)
+{
+    (void) pxMBPortCBTimerExpired();
 }
 
-#endif
+static void timer_timeout_ind(void* parameter)
+{
+    prvvTIMERExpiredISR();
+}
diff --git a/components/net/freemodbus/port/porttimer_m.c b/components/net/freemodbus/port/porttimer_m.c
new file mode 100644
index 0000000000..00441bfd1c
--- /dev/null
+++ b/components/net/freemodbus/port/porttimer_m.c
@@ -0,0 +1,107 @@
+/*
+ * FreeModbus Libary: RT-Thread Port
+ * Copyright (C) 2013 Armink <[email protected]>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * File: $Id: porttimer_m.c,v 1.60 2013/08/13 15:07:05 Armink add Master Functions$
+ */
+
+/* ----------------------- Platform includes --------------------------------*/
+#include "port.h"
+
+/* ----------------------- Modbus includes ----------------------------------*/
+#include "mb.h"
+#include "mb_m.h"
+#include "mbport.h"
+
+#if MB_MASTER_RTU_ENABLED > 0 || MB_MASTER_ASCII_ENABLED > 0
+/* ----------------------- Variables ----------------------------------------*/
+static USHORT usT35TimeOut50us;
+static struct rt_timer timer;
+static void prvvTIMERExpiredISR(void);
+static void timer_timeout_ind(void* parameter);
+
+/* ----------------------- static functions ---------------------------------*/
+static void prvvTIMERExpiredISR(void);
+
+/* ----------------------- Start implementation -----------------------------*/
+BOOL xMBMasterPortTimersInit(USHORT usTimeOut50us)
+{
+    /* backup T35 ticks */
+    usT35TimeOut50us = usTimeOut50us;
+
+    rt_timer_init(&timer, "master timer",
+                   timer_timeout_ind, /* bind timeout callback function */
+                   RT_NULL,
+                   (50 * usT35TimeOut50us) / (1000 * 1000 / RT_TICK_PER_SECOND),
+                   RT_TIMER_FLAG_ONE_SHOT); /* one shot */
+
+    return TRUE;
+}
+
+void vMBMasterPortTimersT35Enable()
+{
+    rt_tick_t timer_tick = (50 * usT35TimeOut50us)
+            / (1000 * 1000 / RT_TICK_PER_SECOND);
+
+    /* Set current timer mode, don't change it.*/
+    vMBMasterSetCurTimerMode(MB_TMODE_T35);
+
+    rt_timer_control(&timer, RT_TIMER_CTRL_SET_TIME, &timer_tick);
+
+    rt_timer_start(&timer);
+}
+
+void vMBMasterPortTimersConvertDelayEnable()
+{
+    rt_tick_t timer_tick = MB_MASTER_DELAY_MS_CONVERT * RT_TICK_PER_SECOND / 1000;
+
+    /* Set current timer mode, don't change it.*/
+    vMBMasterSetCurTimerMode(MB_TMODE_CONVERT_DELAY);
+
+    rt_timer_control(&timer, RT_TIMER_CTRL_SET_TIME, &timer_tick);
+
+    rt_timer_start(&timer);
+}
+
+void vMBMasterPortTimersRespondTimeoutEnable()
+{
+    rt_tick_t timer_tick = MB_MASTER_TIMEOUT_MS_RESPOND * RT_TICK_PER_SECOND / 1000;
+
+    /* Set current timer mode, don't change it.*/
+    vMBMasterSetCurTimerMode(MB_TMODE_RESPOND_TIMEOUT);
+
+    rt_timer_control(&timer, RT_TIMER_CTRL_SET_TIME, &timer_tick);
+
+    rt_timer_start(&timer);
+}
+
+void vMBMasterPortTimersDisable()
+{
+    rt_timer_stop(&timer);
+}
+
+void prvvTIMERExpiredISR(void)
+{
+    (void) pxMBMasterPortCBTimerExpired();
+}
+
+static void timer_timeout_ind(void* parameter)
+{
+    prvvTIMERExpiredISR();
+}
+
+#endif
diff --git a/components/net/freemodbus/port/user_mb_app.c b/components/net/freemodbus/port/user_mb_app.c
new file mode 100644
index 0000000000..8da7376336
--- /dev/null
+++ b/components/net/freemodbus/port/user_mb_app.c
@@ -0,0 +1,286 @@
+/*
+ * FreeModbus Libary: user callback functions and buffer define in slave mode
+ * Copyright (C) 2013 Armink <[email protected]>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * File: $Id: user_mb_app.c,v 1.60 2013/11/23 11:49:05 Armink $
+ */
+#include "user_mb_app.h"
+
+/*------------------------Slave mode use these variables----------------------*/
+//Slave mode:DiscreteInputs variables
+USHORT   usSDiscInStart                               = S_DISCRETE_INPUT_START;
+#if S_DISCRETE_INPUT_NDISCRETES%8
+UCHAR    ucSDiscInBuf[S_DISCRETE_INPUT_NDISCRETES/8+1];
+#else
+UCHAR    ucSDiscInBuf[S_DISCRETE_INPUT_NDISCRETES/8]  ;
+#endif
+//Slave mode:Coils variables
+USHORT   usSCoilStart                                 = S_COIL_START;
+#if S_COIL_NCOILS%8
+UCHAR    ucSCoilBuf[S_COIL_NCOILS/8+1]                ;
+#else
+UCHAR    ucSCoilBuf[S_COIL_NCOILS/8]                  ;
+#endif
+//Slave mode:InputRegister variables
+USHORT   usSRegInStart                                = S_REG_INPUT_START;
+USHORT   usSRegInBuf[S_REG_INPUT_NREGS]               ;
+//Slave mode:HoldingRegister variables
+USHORT   usSRegHoldStart                              = S_REG_HOLDING_START;
+USHORT   usSRegHoldBuf[S_REG_HOLDING_NREGS]           ;
+
+/**
+ * Modbus slave input register callback function.
+ *
+ * @param pucRegBuffer input register buffer
+ * @param usAddress input register address
+ * @param usNRegs input register number
+ *
+ * @return result
+ */
+eMBErrorCode eMBRegInputCB(UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNRegs )
+{
+    eMBErrorCode    eStatus = MB_ENOERR;
+    USHORT          iRegIndex;
+    USHORT *        pusRegInputBuf;
+    USHORT          REG_INPUT_START;
+    USHORT          REG_INPUT_NREGS;
+    USHORT          usRegInStart;
+
+    pusRegInputBuf = usSRegInBuf;
+    REG_INPUT_START = S_REG_INPUT_START;
+    REG_INPUT_NREGS = S_REG_INPUT_NREGS;
+    usRegInStart = usSRegInStart;
+
+    /* it already plus one in modbus function method. */
+    usAddress--;
+
+    if ((usAddress >= REG_INPUT_START)
+            && (usAddress + usNRegs <= REG_INPUT_START + REG_INPUT_NREGS))
+    {
+        iRegIndex = usAddress - usRegInStart;
+        while (usNRegs > 0)
+        {
+            *pucRegBuffer++ = (UCHAR) (pusRegInputBuf[iRegIndex] >> 8);
+            *pucRegBuffer++ = (UCHAR) (pusRegInputBuf[iRegIndex] & 0xFF);
+            iRegIndex++;
+            usNRegs--;
+        }
+    }
+    else
+    {
+        eStatus = MB_ENOREG;
+    }
+
+    return eStatus;
+}
+
+/**
+ * Modbus slave holding register callback function.
+ *
+ * @param pucRegBuffer holding register buffer
+ * @param usAddress holding register address
+ * @param usNRegs holding register number
+ * @param eMode read or write
+ *
+ * @return result
+ */
+eMBErrorCode eMBRegHoldingCB(UCHAR * pucRegBuffer, USHORT usAddress,
+        USHORT usNRegs, eMBRegisterMode eMode)
+{
+    eMBErrorCode    eStatus = MB_ENOERR;
+    USHORT          iRegIndex;
+    USHORT *        pusRegHoldingBuf;
+    USHORT          REG_HOLDING_START;
+    USHORT          REG_HOLDING_NREGS;
+    USHORT          usRegHoldStart;
+
+    pusRegHoldingBuf = usSRegHoldBuf;
+    REG_HOLDING_START = S_REG_HOLDING_START;
+    REG_HOLDING_NREGS = S_REG_HOLDING_NREGS;
+    usRegHoldStart = usSRegHoldStart;
+
+    /* it already plus one in modbus function method. */
+    usAddress--;
+
+    if ((usAddress >= REG_HOLDING_START)
+            && (usAddress + usNRegs <= REG_HOLDING_START + REG_HOLDING_NREGS))
+    {
+        iRegIndex = usAddress - usRegHoldStart;
+        switch (eMode)
+        {
+        /* read current register values from the protocol stack. */
+        case MB_REG_READ:
+            while (usNRegs > 0)
+            {
+                *pucRegBuffer++ = (UCHAR) (pusRegHoldingBuf[iRegIndex] >> 8);
+                *pucRegBuffer++ = (UCHAR) (pusRegHoldingBuf[iRegIndex] & 0xFF);
+                iRegIndex++;
+                usNRegs--;
+            }
+            break;
+
+        /* write current register values with new values from the protocol stack. */
+        case MB_REG_WRITE:
+            while (usNRegs > 0)
+            {
+                pusRegHoldingBuf[iRegIndex] = *pucRegBuffer++ << 8;
+                pusRegHoldingBuf[iRegIndex] |= *pucRegBuffer++;
+                iRegIndex++;
+                usNRegs--;
+            }
+            break;
+        }
+    }
+    else
+    {
+        eStatus = MB_ENOREG;
+    }
+    return eStatus;
+}
+
+/**
+ * Modbus slave coils callback function.
+ *
+ * @param pucRegBuffer coils buffer
+ * @param usAddress coils address
+ * @param usNCoils coils number
+ * @param eMode read or write
+ *
+ * @return result
+ */
+eMBErrorCode eMBRegCoilsCB(UCHAR * pucRegBuffer, USHORT usAddress,
+        USHORT usNCoils, eMBRegisterMode eMode)
+{
+    eMBErrorCode    eStatus = MB_ENOERR;
+    USHORT          iRegIndex , iRegBitIndex , iNReg;
+    UCHAR *         pucCoilBuf;
+    USHORT          COIL_START;
+    USHORT          COIL_NCOILS;
+    USHORT          usCoilStart;
+    iNReg =  usNCoils / 8 + 1;
+
+    pucCoilBuf = ucSCoilBuf;
+    COIL_START = S_COIL_START;
+    COIL_NCOILS = S_COIL_NCOILS;
+    usCoilStart = usSCoilStart;
+
+    /* it already plus one in modbus function method. */
+    usAddress--;
+
+    if( ( usAddress >= COIL_START ) &&
+        ( usAddress + usNCoils <= COIL_START + COIL_NCOILS ) )
+    {
+        iRegIndex = (USHORT) (usAddress - usCoilStart) / 8;
+        iRegBitIndex = (USHORT) (usAddress - usCoilStart) % 8;
+        switch ( eMode )
+        {
+        /* read current coil values from the protocol stack. */
+        case MB_REG_READ:
+            while (iNReg > 0)
+            {
+                *pucRegBuffer++ = xMBUtilGetBits(&pucCoilBuf[iRegIndex++],
+                        iRegBitIndex, 8);
+                iNReg--;
+            }
+            pucRegBuffer--;
+            /* last coils */
+            usNCoils = usNCoils % 8;
+            /* filling zero to high bit */
+            *pucRegBuffer = *pucRegBuffer << (8 - usNCoils);
+            *pucRegBuffer = *pucRegBuffer >> (8 - usNCoils);
+            break;
+
+            /* write current coil values with new values from the protocol stack. */
+        case MB_REG_WRITE:
+            while (iNReg > 1)
+            {
+                xMBUtilSetBits(&pucCoilBuf[iRegIndex++], iRegBitIndex, 8,
+                        *pucRegBuffer++);
+                iNReg--;
+            }
+            /* last coils */
+            usNCoils = usNCoils % 8;
+            /* xMBUtilSetBits has bug when ucNBits is zero */
+            if (usNCoils != 0)
+            {
+                xMBUtilSetBits(&pucCoilBuf[iRegIndex++], iRegBitIndex, usNCoils,
+                        *pucRegBuffer++);
+            }
+            break;
+        }
+    }
+    else
+    {
+        eStatus = MB_ENOREG;
+    }
+    return eStatus;
+}
+
+/**
+ * Modbus slave discrete callback function.
+ *
+ * @param pucRegBuffer discrete buffer
+ * @param usAddress discrete address
+ * @param usNDiscrete discrete number
+ *
+ * @return result
+ */
+eMBErrorCode eMBRegDiscreteCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNDiscrete )
+{
+    eMBErrorCode    eStatus = MB_ENOERR;
+    USHORT          iRegIndex , iRegBitIndex , iNReg;
+    UCHAR *         pucDiscreteInputBuf;
+    USHORT          DISCRETE_INPUT_START;
+    USHORT          DISCRETE_INPUT_NDISCRETES;
+    USHORT          usDiscreteInputStart;
+    iNReg =  usNDiscrete / 8 + 1;
+
+    pucDiscreteInputBuf = ucSDiscInBuf;
+    DISCRETE_INPUT_START = S_DISCRETE_INPUT_START;
+    DISCRETE_INPUT_NDISCRETES = S_DISCRETE_INPUT_NDISCRETES;
+    usDiscreteInputStart = usSDiscInStart;
+
+    /* it already plus one in modbus function method. */
+    usAddress--;
+
+    if ((usAddress >= DISCRETE_INPUT_START)
+            && (usAddress + usNDiscrete    <= DISCRETE_INPUT_START + DISCRETE_INPUT_NDISCRETES))
+    {
+        iRegIndex = (USHORT) (usAddress - usDiscreteInputStart) / 8;
+        iRegBitIndex = (USHORT) (usAddress - usDiscreteInputStart) % 8;
+
+        while (iNReg > 0)
+        {
+            *pucRegBuffer++ = xMBUtilGetBits(&pucDiscreteInputBuf[iRegIndex++],
+                    iRegBitIndex, 8);
+            iNReg--;
+        }
+        pucRegBuffer--;
+        /* last discrete */
+        usNDiscrete = usNDiscrete % 8;
+        /* filling zero to high bit */
+        *pucRegBuffer = *pucRegBuffer << (8 - usNDiscrete);
+        *pucRegBuffer = *pucRegBuffer >> (8 - usNDiscrete);
+    }
+    else
+    {
+        eStatus = MB_ENOREG;
+    }
+
+    return eStatus;
+}
+
diff --git a/components/net/freemodbus/port/user_mb_app.h b/components/net/freemodbus/port/user_mb_app.h
new file mode 100644
index 0000000000..864c3860bf
--- /dev/null
+++ b/components/net/freemodbus/port/user_mb_app.h
@@ -0,0 +1,46 @@
+#ifndef    USER_APP
+#define USER_APP
+/* ----------------------- Modbus includes ----------------------------------*/
+#include "mb.h"
+#include "mb_m.h"
+#include "mbconfig.h"
+#include "mbframe.h"
+#include "mbutils.h"
+
+/* -----------------------Slave Defines -------------------------------------*/
+#define S_DISCRETE_INPUT_START        0
+#define S_DISCRETE_INPUT_NDISCRETES   16
+#define S_COIL_START                  0
+#define S_COIL_NCOILS                 64
+#define S_REG_INPUT_START             0
+#define S_REG_INPUT_NREGS             100
+#define S_REG_HOLDING_START           0
+#define S_REG_HOLDING_NREGS           100
+/* salve mode: holding register's all address */
+#define          S_HD_RESERVE                     0
+/* salve mode: input register's all address */
+#define          S_IN_RESERVE                     0
+/* salve mode: coil's all address */
+#define          S_CO_RESERVE                     0
+/* salve mode: discrete's all address */
+#define          S_DI_RESERVE                     0
+
+/* -----------------------Master Defines -------------------------------------*/
+#define M_DISCRETE_INPUT_START        0
+#define M_DISCRETE_INPUT_NDISCRETES   16
+#define M_COIL_START                  0
+#define M_COIL_NCOILS                 64
+#define M_REG_INPUT_START             0
+#define M_REG_INPUT_NREGS             100
+#define M_REG_HOLDING_START           0
+#define M_REG_HOLDING_NREGS           100
+/* master mode: holding register's all address */
+#define          M_HD_RESERVE                     0
+/* master mode: input register's all address */
+#define          M_IN_RESERVE                     0
+/* master mode: coil's all address */
+#define          M_CO_RESERVE                     0
+/* master mode: discrete's all address */
+#define          M_DI_RESERVE                     0
+
+#endif
diff --git a/components/net/freemodbus/port/user_mb_app_m.c b/components/net/freemodbus/port/user_mb_app_m.c
new file mode 100644
index 0000000000..12fabf21ac
--- /dev/null
+++ b/components/net/freemodbus/port/user_mb_app_m.c
@@ -0,0 +1,294 @@
+/*
+ * FreeModbus Libary: user callback functions and buffer define in master mode
+ * Copyright (C) 2013 Armink <[email protected]>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * File: $Id: user_mb_app_m.c,v 1.60 2013/11/23 11:49:05 Armink $
+ */
+#include "user_mb_app.h"
+
+/*-----------------------Master mode use these variables----------------------*/
+#if MB_MASTER_RTU_ENABLED > 0 || MB_MASTER_ASCII_ENABLED > 0
+//Master mode:DiscreteInputs variables
+USHORT   usMDiscInStart                             = M_DISCRETE_INPUT_START;
+#if      M_DISCRETE_INPUT_NDISCRETES%8
+UCHAR    ucMDiscInBuf[MB_MASTER_TOTAL_SLAVE_NUM][M_DISCRETE_INPUT_NDISCRETES/8+1];
+#else
+UCHAR    ucMDiscInBuf[MB_MASTER_TOTAL_SLAVE_NUM][M_DISCRETE_INPUT_NDISCRETES/8];
+#endif
+//Master mode:Coils variables
+USHORT   usMCoilStart                               = M_COIL_START;
+#if      M_COIL_NCOILS%8
+UCHAR    ucMCoilBuf[MB_MASTER_TOTAL_SLAVE_NUM][M_COIL_NCOILS/8+1];
+#else
+UCHAR    ucMCoilBuf[MB_MASTER_TOTAL_SLAVE_NUM][M_COIL_NCOILS/8];
+#endif
+//Master mode:InputRegister variables
+USHORT   usMRegInStart                              = M_REG_INPUT_START;
+USHORT   usMRegInBuf[MB_MASTER_TOTAL_SLAVE_NUM][M_REG_INPUT_NREGS];
+//Master mode:HoldingRegister variables
+USHORT   usMRegHoldStart                            = M_REG_HOLDING_START;
+USHORT   usMRegHoldBuf[MB_MASTER_TOTAL_SLAVE_NUM][M_REG_HOLDING_NREGS];
+
+/**
+ * Modbus master input register callback function.
+ *
+ * @param pucRegBuffer input register buffer
+ * @param usAddress input register address
+ * @param usNRegs input register number
+ *
+ * @return result
+ */
+eMBErrorCode eMBMasterRegInputCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNRegs )
+{
+    eMBErrorCode    eStatus = MB_ENOERR;
+    USHORT          iRegIndex;
+    USHORT *        pusRegInputBuf;
+    USHORT          REG_INPUT_START;
+    USHORT          REG_INPUT_NREGS;
+    USHORT          usRegInStart;
+
+    pusRegInputBuf = usMRegInBuf[ucMBMasterGetDestAddress() - 1];
+    REG_INPUT_START = M_REG_INPUT_START;
+    REG_INPUT_NREGS = M_REG_INPUT_NREGS;
+    usRegInStart = usMRegInStart;
+
+    /* it already plus one in modbus function method. */
+    usAddress--;
+
+    if ((usAddress >= REG_INPUT_START)
+            && (usAddress + usNRegs <= REG_INPUT_START + REG_INPUT_NREGS))
+    {
+        iRegIndex = usAddress - usRegInStart;
+        while (usNRegs > 0)
+        {
+            pusRegInputBuf[iRegIndex] = *pucRegBuffer++ << 8;
+            pusRegInputBuf[iRegIndex] |= *pucRegBuffer++;
+            iRegIndex++;
+            usNRegs--;
+        }
+    }
+    else
+    {
+        eStatus = MB_ENOREG;
+    }
+
+    return eStatus;
+}
+
+/**
+ * Modbus master holding register callback function.
+ *
+ * @param pucRegBuffer holding register buffer
+ * @param usAddress holding register address
+ * @param usNRegs holding register number
+ * @param eMode read or write
+ *
+ * @return result
+ */
+eMBErrorCode eMBMasterRegHoldingCB(UCHAR * pucRegBuffer, USHORT usAddress,
+        USHORT usNRegs, eMBRegisterMode eMode)
+{
+    eMBErrorCode    eStatus = MB_ENOERR;
+    USHORT          iRegIndex;
+    USHORT *        pusRegHoldingBuf;
+    USHORT          REG_HOLDING_START;
+    USHORT          REG_HOLDING_NREGS;
+    USHORT          usRegHoldStart;
+
+    pusRegHoldingBuf = usMRegHoldBuf[ucMBMasterGetDestAddress() - 1];
+    REG_HOLDING_START = M_REG_HOLDING_START;
+    REG_HOLDING_NREGS = M_REG_HOLDING_NREGS;
+    usRegHoldStart = usMRegHoldStart;
+    /* if mode is read, the master will write the received date to buffer. */
+    eMode = MB_REG_WRITE;
+
+    /* it already plus one in modbus function method. */
+    usAddress--;
+
+    if ((usAddress >= REG_HOLDING_START)
+            && (usAddress + usNRegs <= REG_HOLDING_START + REG_HOLDING_NREGS))
+    {
+        iRegIndex = usAddress - usRegHoldStart;
+        switch (eMode)
+        {
+        /* read current register values from the protocol stack. */
+        case MB_REG_READ:
+            while (usNRegs > 0)
+            {
+                *pucRegBuffer++ = (UCHAR) (pusRegHoldingBuf[iRegIndex] >> 8);
+                *pucRegBuffer++ = (UCHAR) (pusRegHoldingBuf[iRegIndex] & 0xFF);
+                iRegIndex++;
+                usNRegs--;
+            }
+            break;
+        /* write current register values with new values from the protocol stack. */
+        case MB_REG_WRITE:
+            while (usNRegs > 0)
+            {
+                pusRegHoldingBuf[iRegIndex] = *pucRegBuffer++ << 8;
+                pusRegHoldingBuf[iRegIndex] |= *pucRegBuffer++;
+                iRegIndex++;
+                usNRegs--;
+            }
+            break;
+        }
+    }
+    else
+    {
+        eStatus = MB_ENOREG;
+    }
+    return eStatus;
+}
+
+/**
+ * Modbus master coils callback function.
+ *
+ * @param pucRegBuffer coils buffer
+ * @param usAddress coils address
+ * @param usNCoils coils number
+ * @param eMode read or write
+ *
+ * @return result
+ */
+eMBErrorCode eMBMasterRegCoilsCB(UCHAR * pucRegBuffer, USHORT usAddress,
+        USHORT usNCoils, eMBRegisterMode eMode)
+{
+    eMBErrorCode    eStatus = MB_ENOERR;
+    USHORT          iRegIndex , iRegBitIndex , iNReg;
+    UCHAR *         pucCoilBuf;
+    USHORT          COIL_START;
+    USHORT          COIL_NCOILS;
+    USHORT          usCoilStart;
+    iNReg =  usNCoils / 8 + 1;
+
+    pucCoilBuf = ucMCoilBuf[ucMBMasterGetDestAddress() - 1];
+    COIL_START = M_COIL_START;
+    COIL_NCOILS = M_COIL_NCOILS;
+    usCoilStart = usMCoilStart;
+
+    /* if mode is read,the master will write the received date to buffer. */
+    eMode = MB_REG_WRITE;
+
+    /* it already plus one in modbus function method. */
+    usAddress--;
+
+    if ((usAddress >= COIL_START)
+            && (usAddress + usNCoils <= COIL_START + COIL_NCOILS))
+    {
+        iRegIndex = (USHORT) (usAddress - usCoilStart) / 8;
+        iRegBitIndex = (USHORT) (usAddress - usCoilStart) % 8;
+        switch (eMode)
+        {
+         /* read current coil values from the protocol stack. */
+        case MB_REG_READ:
+            while (iNReg > 0)
+            {
+                *pucRegBuffer++ = xMBUtilGetBits(&pucCoilBuf[iRegIndex++],
+                        iRegBitIndex, 8);
+                iNReg--;
+            }
+            pucRegBuffer--;
+            /* last coils */
+            usNCoils = usNCoils % 8;
+            /* filling zero to high bit */
+            *pucRegBuffer = *pucRegBuffer << (8 - usNCoils);
+            *pucRegBuffer = *pucRegBuffer >> (8 - usNCoils);
+            break;
+
+        /* write current coil values with new values from the protocol stack. */
+        case MB_REG_WRITE:
+            while (iNReg > 1)
+            {
+                xMBUtilSetBits(&pucCoilBuf[iRegIndex++], iRegBitIndex, 8,
+                        *pucRegBuffer++);
+                iNReg--;
+            }
+            /* last coils */
+            usNCoils = usNCoils % 8;
+            /* xMBUtilSetBits has bug when ucNBits is zero */
+            if (usNCoils != 0)
+            {
+                xMBUtilSetBits(&pucCoilBuf[iRegIndex++], iRegBitIndex, usNCoils,
+                        *pucRegBuffer++);
+            }
+            break;
+        }
+    }
+    else
+    {
+        eStatus = MB_ENOREG;
+    }
+    return eStatus;
+}
+
+/**
+ * Modbus master discrete callback function.
+ *
+ * @param pucRegBuffer discrete buffer
+ * @param usAddress discrete address
+ * @param usNDiscrete discrete number
+ *
+ * @return result
+ */
+eMBErrorCode eMBMasterRegDiscreteCB( UCHAR * pucRegBuffer, USHORT usAddress, USHORT usNDiscrete )
+{
+    eMBErrorCode    eStatus = MB_ENOERR;
+    USHORT          iRegIndex , iRegBitIndex , iNReg;
+    UCHAR *         pucDiscreteInputBuf;
+    USHORT          DISCRETE_INPUT_START;
+    USHORT          DISCRETE_INPUT_NDISCRETES;
+    USHORT          usDiscreteInputStart;
+    iNReg =  usNDiscrete / 8 + 1;
+
+    pucDiscreteInputBuf = ucMDiscInBuf[ucMBMasterGetDestAddress() - 1];
+    DISCRETE_INPUT_START = M_DISCRETE_INPUT_START;
+    DISCRETE_INPUT_NDISCRETES = M_DISCRETE_INPUT_NDISCRETES;
+    usDiscreteInputStart = usMDiscInStart;
+
+    /* it already plus one in modbus function method. */
+    usAddress--;
+
+    if ((usAddress >= DISCRETE_INPUT_START)
+            && (usAddress + usNDiscrete    <= DISCRETE_INPUT_START + DISCRETE_INPUT_NDISCRETES))
+    {
+        iRegIndex = (USHORT) (usAddress - usDiscreteInputStart) / 8;
+        iRegBitIndex = (USHORT) (usAddress - usDiscreteInputStart) % 8;
+
+        /* write current discrete values with new values from the protocol stack. */
+        while (iNReg > 1)
+        {
+            xMBUtilSetBits(&pucDiscreteInputBuf[iRegIndex++], iRegBitIndex, 8,
+                    *pucRegBuffer++);
+            iNReg--;
+        }
+        /* last discrete */
+        usNDiscrete = usNDiscrete % 8;
+        /* xMBUtilSetBits has bug when ucNBits is zero */
+        if (usNDiscrete != 0)
+        {
+            xMBUtilSetBits(&pucDiscreteInputBuf[iRegIndex++], iRegBitIndex,
+                    usNDiscrete, *pucRegBuffer++);
+        }
+    }
+    else
+    {
+        eStatus = MB_ENOREG;
+    }
+
+    return eStatus;
+}
+#endif
diff --git a/components/net/lwip-1.4.1/src/core/ipv4/ip.c b/components/net/lwip-1.4.1/src/core/ipv4/ip.c
index 95d2db404c..17bcd3929a 100644
--- a/components/net/lwip-1.4.1/src/core/ipv4/ip.c
+++ b/components/net/lwip-1.4.1/src/core/ipv4/ip.c
@@ -312,6 +312,11 @@ ip_input(struct pbuf *p, struct netif *inp)
   int check_ip_src=1;
 #endif /* IP_ACCEPT_LINK_LAYER_ADDRESSING */
 
+#if IP_NAT
+  extern u8_t ip_nat_input(struct pbuf *p);
+  extern u8_t ip_nat_out(struct pbuf *p);
+#endif
+
   IP_STATS_INC(ip.recv);
   snmp_inc_ipinreceives();
 
@@ -487,15 +492,30 @@ ip_input(struct pbuf *p, struct netif *inp)
 
   /* packet not for us? */
   if (netif == NULL) {
+#if IP_FORWARD || IP_NAT
+    u8_t taken = 0;
+#endif /* IP_FORWARD || IP_NAT */
     /* packet not for us, route or discard */
     LWIP_DEBUGF(IP_DEBUG | LWIP_DBG_TRACE, ("ip_input: packet not for us.\n"));
-#if IP_FORWARD
+#if IP_FORWARD || IP_NAT
     /* non-broadcast packet? */
-    if (!ip_addr_isbroadcast(&current_iphdr_dest, inp)) {
-      /* try to forward IP packet on (other) interfaces */
-      ip_forward(p, iphdr, inp);
-    } else
+    if (!ip_addr_isbroadcast(&(iphdr->dest), inp)) {
+#if IP_NAT
+      /* check if we want to perform NAT with this packet. */
+      taken = ip_nat_out(p);
+      if (!taken)
+#endif /* IP_NAT */
+      {
+#if IP_FORWARD
+        /* try to forward IP packet on (other) interfaces */
+        if (ip_forward(p, iphdr, inp) != NULL) {
+          taken = 1;
+        }
 #endif /* IP_FORWARD */
+      }
+    }
+    if (!taken)
+#endif /* IP_FORWARD || IP_NAT */
     {
       snmp_inc_ipinaddrerrors();
       snmp_inc_ipindiscards();
@@ -553,6 +573,13 @@ ip_input(struct pbuf *p, struct netif *inp)
   current_netif = inp;
   current_header = iphdr;
 
+#if IP_NAT
+  if (!ip_addr_isbroadcast(&(iphdr->dest), inp) &&
+      (ip_nat_input(p) != 0)) {
+     LWIP_DEBUGF(IP_DEBUG, ("ip_input: packet consumed by nat layer\n"));
+  } else
+#endif /* IP_NAT */
+
 #if LWIP_RAW
   /* raw input did not eat the packet? */
   if (raw_input(p, inp) == 0)
diff --git a/components/net/lwip-1.4.1/src/lwipopts.h b/components/net/lwip-1.4.1/src/lwipopts.h
index bff172e280..cb7def8ae6 100644
--- a/components/net/lwip-1.4.1/src/lwipopts.h
+++ b/components/net/lwip-1.4.1/src/lwipopts.h
@@ -161,6 +161,12 @@
  */
 #define SYS_LIGHTWEIGHT_PROT        (NO_SYS==0)
 
+#ifdef LWIP_USING_NAT
+#define IP_NAT                      1
+#else
+#define IP_NAT                      0
+#endif
+
 /* ---------- TCP options ---------- */
 #ifdef RT_LWIP_TCP
 #define LWIP_TCP                    1
diff --git a/components/net/lwip_dhcpd/SConscript b/components/net/lwip_dhcpd/SConscript
new file mode 100644
index 0000000000..d5704c8c8b
--- /dev/null
+++ b/components/net/lwip_dhcpd/SConscript
@@ -0,0 +1,10 @@
+from building import *
+
+cwd = GetCurrentDir()
+src = Glob('*.c')
+
+CPPPATH = [cwd]
+
+group = DefineGroup('LwIP', src, depend = ['RT_USING_LWIP', 'LWIP_USING_DHCPD'], CPPPATH = CPPPATH)
+
+Return('group')
diff --git a/components/net/lwip_dhcpd/dhcp_server.c b/components/net/lwip_dhcpd/dhcp_server.c
new file mode 100644
index 0000000000..47547a598b
--- /dev/null
+++ b/components/net/lwip_dhcpd/dhcp_server.c
@@ -0,0 +1,398 @@
+/*
+ * File      : dhcp_server.c
+ *             A simple DHCP server implementation
+ *
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2013-2015, Shanghai Real-Thread Technology Co., Ltd
+ * http://www.rt-thread.com
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2013-01-30     aozima       the first version
+ * 2013-08-08     aozima       support different network segments.
+ * 2015-01-30     bernard      release to RT-Thread RTOS.
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <rtthread.h>
+
+#include <lwip/opt.h>
+#include <lwip/sockets.h>
+#include <lwip/inet_chksum.h>
+#include <netif/etharp.h>
+#include <netif/ethernetif.h>
+#include <lwip/ip.h>
+
+/* DHCP server option */
+
+/* allocated client ip range */
+#ifndef DHCPD_CLIENT_IP_MIN
+#define DHCPD_CLIENT_IP_MIN     2
+#endif
+#ifndef DHCPD_CLIENT_IP_MAX
+#define DHCPD_CLIENT_IP_MAX     254
+#endif
+
+/* the DHCP server address */
+#ifndef DHCPD_SERVER_IPADDR0
+#define DHCPD_SERVER_IPADDR0      192UL
+#define DHCPD_SERVER_IPADDR1      168UL
+#define DHCPD_SERVER_IPADDR2      169UL
+#define DHCPD_SERVER_IPADDR3      1UL
+#endif
+
+//#define DHCP_DEBUG_PRINTF
+
+#ifdef  DHCP_DEBUG_PRINTF
+#define DEBUG_PRINTF        rt_kprintf("[DHCP] "); rt_kprintf
+#else
+#define DEBUG_PRINTF(...)
+#endif /* DHCP_DEBUG_PRINTF */
+
+/* we need some routines in the DHCP of lwIP */
+#undef  LWIP_DHCP
+#define LWIP_DHCP   1
+#include <lwip/dhcp.h>
+
+/* buffer size for receive DHCP packet */
+#define BUFSZ               1024
+
+static uint8_t next_client_ip = DHCPD_CLIENT_IP_MIN;
+static rt_err_t _low_level_dhcp_send(struct netif *netif,
+                                     const void *buffer,
+                                     rt_size_t size)
+{
+    struct pbuf *p;
+    struct eth_hdr *ethhdr;
+    struct ip_hdr *iphdr;
+    struct udp_hdr *udphdr;
+
+    p = pbuf_alloc(PBUF_LINK,
+                   SIZEOF_ETH_HDR + sizeof(struct ip_hdr)
+                   + sizeof(struct udp_hdr) + size,
+                   PBUF_RAM);
+    if (p == RT_NULL) return -RT_ENOMEM;
+
+    ethhdr = (struct eth_hdr *)p->payload;
+    iphdr  = (struct ip_hdr *)((char *)ethhdr + SIZEOF_ETH_HDR);
+    udphdr = (struct udp_hdr *)((char *)iphdr + sizeof(struct ip_hdr));
+
+    ETHADDR32_COPY(&ethhdr->dest, (struct eth_addr *)&ethbroadcast);
+    ETHADDR16_COPY(&ethhdr->src, netif->hwaddr);
+    ethhdr->type = PP_HTONS(ETHTYPE_IP);
+
+    iphdr->src.addr  = 0x00000000; /* src: 0.0.0.0 */
+    iphdr->dest.addr = 0xFFFFFFFF; /* src: 255.255.255.255 */
+
+    IPH_VHL_SET(iphdr, 4, IP_HLEN / 4);
+    IPH_TOS_SET(iphdr, 0x00);
+    IPH_LEN_SET(iphdr, htons(IP_HLEN + sizeof(struct udp_hdr) + size));
+    IPH_ID_SET(iphdr, htons(2));
+    IPH_OFFSET_SET(iphdr, 0);
+    IPH_TTL_SET(iphdr, 255);
+    IPH_PROTO_SET(iphdr, IP_PROTO_UDP);
+    IPH_CHKSUM_SET(iphdr, 0);
+    IPH_CHKSUM_SET(iphdr, inet_chksum(iphdr, IP_HLEN));
+
+    udphdr->src = htons(DHCP_SERVER_PORT);
+    udphdr->dest = htons(DHCP_CLIENT_PORT);
+    udphdr->len = htons(sizeof(struct udp_hdr) + size);
+    udphdr->chksum = 0;
+
+    memcpy((char *)udphdr + sizeof(struct udp_hdr),
+           buffer, size);
+
+    return netif->linkoutput(netif, p);
+}
+
+static void dhcpd_thread_entry(void *parameter)
+{
+    struct netif *netif = RT_NULL;
+    int sock;
+    int bytes_read;
+    char *recv_data;
+    rt_uint32_t addr_len;
+    struct sockaddr_in server_addr, client_addr;
+    struct dhcp_msg *msg;
+    int optval = 1;
+
+    /* get ethernet interface. */
+    netif = (struct netif*) parameter;
+    RT_ASSERT(netif != RT_NULL);
+
+    /* our DHCP server information */
+    DEBUG_PRINTF("DHCP server IP: %d.%d.%d.%d  client IP: %d.%d.%d.%d-%d\n",
+                 DHCPD_SERVER_IPADDR0, DHCPD_SERVER_IPADDR1,
+                 DHCPD_SERVER_IPADDR2, DHCPD_SERVER_IPADDR3,
+                 DHCPD_SERVER_IPADDR0, DHCPD_SERVER_IPADDR1,
+                 DHCPD_SERVER_IPADDR2, DHCPD_CLIENT_IP_MIN, DHCPD_CLIENT_IP_MAX);
+
+    /* allocate buffer for receive */
+    recv_data = rt_malloc(BUFSZ);
+    if (recv_data == RT_NULL)
+    {
+        /* No memory */
+        DEBUG_PRINTF("Out of memory\n");
+        return;
+    }
+
+    /* create a socket with UDP */
+    if ((sock = socket(AF_INET, SOCK_DGRAM, 0)) == -1)
+    {
+        DEBUG_PRINTF("create socket failed, errno = %d\n", errno);
+        rt_free(recv_data);
+        return;
+    }
+
+    /* set to receive broadcast packet */
+    setsockopt(sock, SOL_SOCKET, SO_BROADCAST, &optval, sizeof(optval));
+
+    /* initialize server address */
+    server_addr.sin_family = AF_INET;
+    server_addr.sin_port = htons(DHCP_SERVER_PORT);
+    server_addr.sin_addr.s_addr = INADDR_ANY;
+    rt_memset(&(server_addr.sin_zero), 0, sizeof(server_addr.sin_zero));
+
+    /* bind socket to the server address */
+    if (bind(sock, (struct sockaddr *)&server_addr,
+             sizeof(struct sockaddr)) == -1)
+    {
+        /* bind failed. */
+        DEBUG_PRINTF("bind server address failed, errno=%d\n", errno);
+        rt_free(recv_data);
+        return;
+    }
+
+    addr_len = sizeof(struct sockaddr);
+    DEBUG_PRINTF("DHCP server listen on port %d...\n", DHCP_SERVER_PORT);
+
+    while (1)
+    {
+        bytes_read = recvfrom(sock, recv_data, BUFSZ - 1, 0,
+                              (struct sockaddr *)&client_addr, &addr_len);
+        if (bytes_read < DHCP_MSG_LEN)
+        {
+            DEBUG_PRINTF("packet too short, wait for next!\n");
+            continue;
+        }
+
+        msg = (struct dhcp_msg *)recv_data;
+        /* check message type to make sure we can handle it */
+        if ((msg->op != DHCP_BOOTREQUEST) || (msg->cookie != PP_HTONL(DHCP_MAGIC_COOKIE)))
+        {
+            continue;
+        }
+
+        /* handler. */
+        {
+            uint8_t *dhcp_opt;
+            uint8_t option;
+            uint8_t length;
+
+            uint8_t message_type = 0;
+            uint8_t finished = 0;
+            uint32_t request_ip  = 0;
+
+            dhcp_opt = (uint8_t *)msg + DHCP_OPTIONS_OFS;
+            while (finished == 0)
+            {
+                option = *dhcp_opt;
+                length = *(dhcp_opt + 1);
+
+                switch (option)
+                {
+                case DHCP_OPTION_REQUESTED_IP:
+                    request_ip = *(dhcp_opt + 2) << 24 | *(dhcp_opt + 3) << 16
+                                 | *(dhcp_opt + 4) << 8 | *(dhcp_opt + 5);
+                    break;
+
+                case DHCP_OPTION_END:
+                    finished = 1;
+                    break;
+
+                case DHCP_OPTION_MESSAGE_TYPE:
+                    message_type = *(dhcp_opt + 2);
+                    break;
+
+                default:
+                    break;
+                } /* switch(option) */
+
+                dhcp_opt += (2 + length);
+            }
+
+            /* reply. */
+            dhcp_opt = (uint8_t *)msg + DHCP_OPTIONS_OFS;
+
+            /* check. */
+            if (request_ip)
+            {
+                uint32_t client_ip = DHCPD_SERVER_IPADDR0 << 24 | DHCPD_SERVER_IPADDR1 << 16
+                                     | DHCPD_SERVER_IPADDR2 << 8 | (next_client_ip);
+
+                if (request_ip != client_ip)
+                {
+                    *dhcp_opt++ = DHCP_OPTION_MESSAGE_TYPE;
+                    *dhcp_opt++ = DHCP_OPTION_MESSAGE_TYPE_LEN;
+                    *dhcp_opt++ = DHCP_NAK;
+                    *dhcp_opt++ = DHCP_OPTION_END;
+
+                    DEBUG_PRINTF("requested IP invalid, reply DHCP_NAK\n");
+                    if (netif != RT_NULL)
+                    {
+                        int send_byte = (dhcp_opt - (uint8_t *)msg);
+                        _low_level_dhcp_send(netif, msg, send_byte);
+                        DEBUG_PRINTF("DHCP server send %d byte\n", send_byte);
+                    }
+                    next_client_ip++;
+                    if (next_client_ip > DHCPD_CLIENT_IP_MAX)
+                        next_client_ip = DHCPD_CLIENT_IP_MIN;
+                    continue;
+                }
+            }
+
+            if (message_type == DHCP_DISCOVER)
+            {
+                DEBUG_PRINTF("request DHCP_DISCOVER\n");
+                DEBUG_PRINTF("reply   DHCP_OFFER\n");
+
+                // DHCP_OPTION_MESSAGE_TYPE
+                *dhcp_opt++ = DHCP_OPTION_MESSAGE_TYPE;
+                *dhcp_opt++ = DHCP_OPTION_MESSAGE_TYPE_LEN;
+                *dhcp_opt++ = DHCP_OFFER;
+
+                // DHCP_OPTION_SERVER_ID
+                *dhcp_opt++ = DHCP_OPTION_SERVER_ID;
+                *dhcp_opt++ = 4;
+                *dhcp_opt++ = DHCPD_SERVER_IPADDR0;
+                *dhcp_opt++ = DHCPD_SERVER_IPADDR1;
+                *dhcp_opt++ = DHCPD_SERVER_IPADDR2;
+                *dhcp_opt++ = DHCPD_SERVER_IPADDR3;
+
+                // DHCP_OPTION_LEASE_TIME
+                *dhcp_opt++ = DHCP_OPTION_LEASE_TIME;
+                *dhcp_opt++ = 4;
+                *dhcp_opt++ = 0x00;
+                *dhcp_opt++ = 0x01;
+                *dhcp_opt++ = 0x51;
+                *dhcp_opt++ = 0x80;
+            }
+            else if (message_type == DHCP_REQUEST)
+            {
+                DEBUG_PRINTF("request DHCP_REQUEST\n");
+                DEBUG_PRINTF("reply   DHCP_ACK\n");
+
+                // DHCP_OPTION_MESSAGE_TYPE
+                *dhcp_opt++ = DHCP_OPTION_MESSAGE_TYPE;
+                *dhcp_opt++ = DHCP_OPTION_MESSAGE_TYPE_LEN;
+                *dhcp_opt++ = DHCP_ACK;
+
+                // DHCP_OPTION_SERVER_ID
+                *dhcp_opt++ = DHCP_OPTION_SERVER_ID;
+                *dhcp_opt++ = 4;
+                *dhcp_opt++ = DHCPD_SERVER_IPADDR0;
+                *dhcp_opt++ = DHCPD_SERVER_IPADDR1;
+                *dhcp_opt++ = DHCPD_SERVER_IPADDR2;
+                *dhcp_opt++ = DHCPD_SERVER_IPADDR3;
+
+                // DHCP_OPTION_SUBNET_MASK
+                *dhcp_opt++ = DHCP_OPTION_SUBNET_MASK;
+                *dhcp_opt++ = 4;
+                *dhcp_opt++ = 0xFF;
+                *dhcp_opt++ = 0xFF;
+                *dhcp_opt++ = 0xFF;
+                *dhcp_opt++ = 0x00;
+
+#ifdef DHCPD_USING_ROUTER
+                // DHCP_OPTION_ROUTER
+                *dhcp_opt++ = DHCP_OPTION_ROUTER;
+                *dhcp_opt++ = 4;
+                *dhcp_opt++ = DHCPD_SERVER_IPADDR0;
+                *dhcp_opt++ = DHCPD_SERVER_IPADDR1;
+                *dhcp_opt++ = DHCPD_SERVER_IPADDR2;
+                *dhcp_opt++ = 1;
+#endif
+
+                // DHCP_OPTION_DNS_SERVER, use the default DNS server address in lwIP
+                *dhcp_opt++ = DHCP_OPTION_DNS_SERVER;
+                *dhcp_opt++ = 4;
+                *dhcp_opt++ = 208;
+                *dhcp_opt++ = 67;
+                *dhcp_opt++ = 222;
+                *dhcp_opt++ = 222;
+
+                // DHCP_OPTION_LEASE_TIME
+                *dhcp_opt++ = DHCP_OPTION_LEASE_TIME;
+                *dhcp_opt++ = 4;
+                *dhcp_opt++ = 0x00;
+                *dhcp_opt++ = 0x01;
+                *dhcp_opt++ = 0x51;
+                *dhcp_opt++ = 0x80;
+            }
+            else
+            {
+                DEBUG_PRINTF("un handle message:%d\n", message_type);
+            }
+
+            // append DHCP_OPTION_END
+            *dhcp_opt++ = DHCP_OPTION_END;
+
+            /* send reply. */
+            if ((message_type == DHCP_DISCOVER) || (message_type == DHCP_REQUEST))
+            {
+                msg->op = DHCP_BOOTREPLY;
+                IP4_ADDR(&msg->yiaddr,
+                         DHCPD_SERVER_IPADDR0, DHCPD_SERVER_IPADDR1,
+                         DHCPD_SERVER_IPADDR2, next_client_ip);
+
+                client_addr.sin_addr.s_addr = INADDR_BROADCAST;
+
+                if (netif != RT_NULL)
+                {
+                    int send_byte = (dhcp_opt - (uint8_t *)msg);
+                    _low_level_dhcp_send(netif, msg, send_byte);
+                    DEBUG_PRINTF("DHCP server send %d byte\n", send_byte);
+                }
+            }
+        } /* handler. */
+    }
+}
+
+void dhcpd_start(char* netif_name)
+{
+    rt_thread_t thread;
+    struct netif *netif = RT_NULL;
+
+    /* find ethernet interface. */
+    netif = netif_find(netif_name);
+    if (netif == RT_NULL)
+    {
+        DEBUG_PRINTF("Not found network interface:%s\n", netif_name);
+    }
+
+    thread = rt_thread_create("dhcpd",
+                              dhcpd_thread_entry, netif,
+                              1024,
+                              RT_THREAD_PRIORITY_MAX - 3,
+                              2);
+    if (thread != RT_NULL)
+    {
+        rt_thread_startup(thread);
+    }
+}
+
diff --git a/components/net/lwip_dhcpd/dhcp_server.h b/components/net/lwip_dhcpd/dhcp_server.h
new file mode 100644
index 0000000000..4bd1163706
--- /dev/null
+++ b/components/net/lwip_dhcpd/dhcp_server.h
@@ -0,0 +1,36 @@
+/*
+ * File      : dhcp_server.h
+ *             A simple DHCP server implementation
+ *
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2013-2015, Shanghai Real-Thread Technology Co., Ltd
+ * http://www.rt-thread.com
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2013-01-30     aozima       the first version
+ * 2013-08-08     aozima       support different network segments.
+ * 2015-01-30     bernard      release to RT-Thread RTOS.
+ */
+
+#ifndef DHCPV4_SERVER_H__
+#define DHCPV4_SERVER_H__
+
+void dhcpd_start(char* netif_name);
+
+#endif
+
diff --git a/components/net/lwip_nat/README.md b/components/net/lwip_nat/README.md
new file mode 100644
index 0000000000..9672a11b54
--- /dev/null
+++ b/components/net/lwip_nat/README.md
@@ -0,0 +1,19 @@
+lwIP NAT componenent
+
+If you want to use lwIP NAT componenent, please define LWIP_USING_NAT in rtconfig.h. 
+
+In this case the network 213.129.231.168/29 is nat'ed when packets are sent to the 
+destination network 10.0.0.0/24 (untypical example - most users will have the other 
+way around).
+
+Use following code to add a NAT entry: 
+
+  ip_nat_entry_t nat_entry;
+ 
+  nat_entry.out_if = (struct netif *)&emac_if1;
+  nat_entry.in_if = (struct netif *)&emac_if2;
+  IP4_ADDR(&nat_entry.source_net, 213, 129, 231, 168);
+  IP4_ADDR(&nat_entry.source_netmask, 255, 255, 255, 248);
+  IP4_ADDR(&nat_entry.dest_net, 10, 0, 0, 0);
+  IP4_ADDR(&nat_entry.source_netmask, 255, 0, 0, 0);
+  ip_nat_add(&_nat_entry);
diff --git a/components/net/lwip_nat/SConscript b/components/net/lwip_nat/SConscript
new file mode 100644
index 0000000000..ce684f677a
--- /dev/null
+++ b/components/net/lwip_nat/SConscript
@@ -0,0 +1,10 @@
+from building import *
+
+cwd = GetCurrentDir()
+src = Glob('*.c')
+
+CPPPATH = [cwd]
+
+group = DefineGroup('LwIP', src, depend = ['RT_USING_LWIP', 'LWIP_USING_NAT'], CPPPATH = CPPPATH)
+
+Return('group')
diff --git a/components/net/lwip_nat/ipv4_nat.c b/components/net/lwip_nat/ipv4_nat.c
new file mode 100644
index 0000000000..13c1877f2c
--- /dev/null
+++ b/components/net/lwip_nat/ipv4_nat.c
@@ -0,0 +1,1154 @@
+/**
+ * NAT - NAT implementation for lwIP supporting TCP/UDP and ICMP.
+ * Copyright (c) 2009 Christian Walter, ?Embedded Solutions, Vienna 2009.
+ *
+ * Copyright (c) 2010 lwIP project ;-)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ */
+
+/*
+ * File      : ipv4_nat.c
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2015, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2015-01-26     Hichard      porting to RT-Thread
+ * 2015-01-27     Bernard      code cleanup for lwIP in RT-Thread
+ */
+
+/*
+ * TODOS:
+ *  - we should decide if we want to use static tables for NAT or a linked
+ *    list.
+ *  - we should allocate icmp ping id if multiple clients are sending
+ *    ping requests.
+ *  - maybe we could hash the identifiers for TCP, ICMP and UDP and use
+ *    a single table structure. This would reduce the code amount although
+ *    it will cost performance.
+ *  - NAT code must check for broadcast addresses and NOT forward
+ *    them.
+ *
+ *  - netif_remove must notify NAT code when a NAT'ed interface is removed
+ *  - allocate NAT entries from a new memp pool instead of the heap
+ *  - let ttl be ticks, not seconds
+ *
+ * HOWTO USE:
+ *
+ * Shows how to create NAT between a PPP interface and an internal NIC.
+ * In this case the network 213.129.231.168/29 is nat'ed when packets
+ * are sent to the destination network 10.0.0.0/24 (untypical example -
+ * most users will have the other way around).
+ *
+ * Step 1) Execute when network interfaces are ready.
+ *
+ * new_nat_entry.out_if = (struct netif *)&PPP_IF;
+ * new_nat_entry.in_if = (struct netif *)&EMAC_if;
+ * IP4_ADDR(&new_nat_entry.source_net, 213, 129, 231, 168);
+ * IP4_ADDR(&new_nat_entry.source_netmask, 255, 255, 255, 248);
+ * IP4_ADDR(&new_nat_entry.dest_net, 10, 0, 0, 0);
+ * IP4_ADDR(&new_nat_entry.source_netmask, 255, 0, 0, 0);
+ * ip_nat_add(&new_nat_entry);
+ */
+
+#include "ipv4_nat.h"
+#include "lwip/opt.h"
+
+#ifdef LWIP_USING_NAT
+
+#include "lwip/ip.h"
+#include "lwip/inet.h"
+#include "lwip/netif.h"
+#include "lwip/ip_addr.h"
+#include "lwip/icmp.h"
+#include "lwip/tcp_impl.h"
+#include "lwip/udp.h"
+#include "lwip/mem.h"
+#include "lwip/sys.h"
+#include "lwip/timers.h"
+#include "netif/etharp.h"
+
+#include <limits.h>
+#include <string.h>
+
+/** Define this to enable debug output of this module */
+#ifndef LWIP_NAT_DEBUG
+#define LWIP_NAT_DEBUG      LWIP_DBG_OFF
+#endif
+
+#define LWIP_NAT_TTL_INFINITE                    (INT_MAX)
+#define LWIP_NAT_DEFAULT_TTL_SECONDS             (128)
+#define LWIP_NAT_FORWARD_HEADER_SIZE_MIN         (sizeof(struct eth_hdr))
+
+#define LWIP_NAT_DEFAULT_STATE_TABLES_ICMP       (4)
+#define LWIP_NAT_DEFAULT_STATE_TABLES_TCP        (32)
+#define LWIP_NAT_DEFAULT_STATE_TABLES_UDP        (32)
+
+#define LWIP_NAT_DEFAULT_TCP_SOURCE_PORT         (40000)
+#define LWIP_NAT_DEFAULT_UDP_SOURCE_PORT         (40000)
+
+#define IPNAT_ENTRY_RESET(x) do { \
+  (x)->ttl = 0; \
+} while(0)
+
+typedef struct ip_nat_conf
+{
+  struct ip_nat_conf *next;
+  ip_nat_entry_t      entry;
+} ip_nat_conf_t;
+
+typedef struct ip_nat_entry_common
+{
+  s32_t           ttl; /* @todo: do we really need this to be signed?? */
+  ip_addr_t       source;
+  ip_addr_t       dest;
+  ip_nat_conf_t   *cfg;
+} ip_nat_entry_common_t;
+
+typedef struct ip_nat_entries_icmp
+{
+  ip_nat_entry_common_t common;
+  u16_t                 id;
+  u16_t                 seqno;
+} ip_nat_entries_icmp_t;
+
+typedef struct ip_nat_entries_tcp
+{
+  ip_nat_entry_common_t common;
+  u16_t                 nport;
+  u16_t                 sport;
+  u16_t                 dport;
+} ip_nat_entries_tcp_t;
+
+typedef struct ip_nat_entries_udp
+{
+  ip_nat_entry_common_t common;
+  u16_t                 nport;
+  u16_t                 sport;
+  u16_t                 dport;
+} ip_nat_entries_udp_t;
+
+typedef union u_nat_entry
+{
+  ip_nat_entry_common_t *cmn;
+  ip_nat_entries_tcp_t  *tcp;
+  ip_nat_entries_icmp_t *icmp;
+  ip_nat_entries_udp_t  *udp;
+} nat_entry_t;
+
+static ip_nat_conf_t *ip_nat_cfg = NULL;
+static ip_nat_entries_icmp_t ip_nat_icmp_table[LWIP_NAT_DEFAULT_STATE_TABLES_ICMP];
+static ip_nat_entries_tcp_t ip_nat_tcp_table[LWIP_NAT_DEFAULT_STATE_TABLES_TCP];
+static ip_nat_entries_udp_t ip_nat_udp_table[LWIP_NAT_DEFAULT_STATE_TABLES_UDP];
+
+/* ----------------------- Static functions (COMMON) --------------------*/
+static void     ip_nat_chksum_adjust(u8_t *chksum, const u8_t *optr, s16_t olen, const u8_t *nptr, s16_t nlen);
+static void     ip_nat_cmn_init(ip_nat_conf_t *nat_config, const struct ip_hdr *iphdr,
+                                 ip_nat_entry_common_t *nat_entry);
+static ip_nat_conf_t *ip_nat_shallnat(const struct ip_hdr *iphdr);
+static void     ip_nat_reset_state(ip_nat_conf_t *cfg);
+
+/* ----------------------- Static functions (DEBUG) ---------------------*/
+#if defined(LWIP_DEBUG) && (LWIP_NAT_DEBUG & LWIP_DBG_ON)
+static void     ip_nat_dbg_dump(const char *msg, const struct ip_hdr *iphdr);
+static void     ip_nat_dbg_dump_ip(const ip_addr_t *addr);
+static void     ip_nat_dbg_dump_icmp_nat_entry(const char *msg, const ip_nat_entries_icmp_t *nat_entry);
+static void     ip_nat_dbg_dump_tcp_nat_entry(const char *msg, const ip_nat_entries_tcp_t *nat_entry);
+static void     ip_nat_dbg_dump_udp_nat_entry(const char *msg, const ip_nat_entries_udp_t *nat_entry);
+static void     ip_nat_dbg_dump_init(ip_nat_conf_t *ip_nat_cfg_new);
+static void     ip_nat_dbg_dump_remove(ip_nat_conf_t *cur);
+#else /* defined(LWIP_DEBUG) && (LWIP_NAT_DEBUG & LWIP_DBG_ON) */
+#define ip_nat_dbg_dump(msg, iphdr)
+#define ip_nat_dbg_dump_ip(addr)
+#define ip_nat_dbg_dump_icmp_nat_entry(msg, nat_entry)
+#define ip_nat_dbg_dump_tcp_nat_entry(msg, nat_entry)
+#define ip_nat_dbg_dump_udp_nat_entry(msg, nat_entry)
+#define ip_nat_dbg_dump_init(ip_nat_cfg_new)
+#define ip_nat_dbg_dump_remove(cur)
+#endif /* defined(LWIP_DEBUG) && (LWIP_NAT_DEBUG & LWIP_DBG_ON) */
+
+/* ----------------------- Static functions (TCP) -----------------------*/
+static ip_nat_entries_tcp_t *ip_nat_tcp_lookup_incoming(const struct ip_hdr *iphdr, const struct tcp_hdr *tcphdr);
+static ip_nat_entries_tcp_t *ip_nat_tcp_lookup_outgoing(ip_nat_conf_t *nat_config,
+                                                         const struct ip_hdr *iphdr, const struct tcp_hdr *tcphdr,
+                                                         u8_t allocate);
+
+/* ----------------------- Static functions (UDP) -----------------------*/
+static ip_nat_entries_udp_t *ip_nat_udp_lookup_incoming(const struct ip_hdr *iphdr, const struct udp_hdr *udphdr);
+static ip_nat_entries_udp_t *ip_nat_udp_lookup_outgoing(ip_nat_conf_t *nat_config,
+                                                         const struct ip_hdr *iphdr, const struct udp_hdr *udphdr,
+                                                         u8_t allocate);
+
+/**
+ * Timer callback function that calls ip_nat_tmr() and reschedules itself.
+ *
+ * @param arg unused argument
+ */
+static void
+nat_timer(void *arg)
+{
+  LWIP_UNUSED_ARG(arg);
+  LWIP_DEBUGF(TIMERS_DEBUG, ("tcpip: nat_timer()\n"));
+
+  ip_nat_tmr();
+  sys_timeout(LWIP_NAT_TMR_INTERVAL_SEC, nat_timer, NULL);
+}
+
+/** Initialize this module */
+void
+ip_nat_init(void)
+{
+  int i;
+  extern void lwip_ip_input_set_hook(int (*hook)(struct pbuf *p, struct netif *inp));
+
+  /* @todo: this can be omitted since we trust static variables
+            to be initialized to zero */
+  for (i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_ICMP; i++) {
+    IPNAT_ENTRY_RESET(&ip_nat_icmp_table[i].common);
+  }
+  for (i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_TCP; i++) {
+    IPNAT_ENTRY_RESET(&ip_nat_tcp_table[i].common);
+  }
+  for (i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_UDP; i++) {
+    IPNAT_ENTRY_RESET(&ip_nat_udp_table[i].common);
+  }
+
+  /* we must lock scheduler to protect following code */
+  rt_enter_critical();
+
+  /* add a lwip timer for NAT */
+  sys_timeout(LWIP_NAT_TMR_INTERVAL_SEC, nat_timer, NULL);
+
+  /* un-protect */
+  rt_exit_critical();
+}
+
+/** Allocate a new ip_nat_conf_t item */
+static ip_nat_conf_t*
+ip_nat_alloc(void)
+{
+  ip_nat_conf_t *ret = (ip_nat_conf_t*)mem_malloc(sizeof(ip_nat_conf_t));
+  return ret;
+}
+
+/** Free a removed ip_nat_conf_t item */
+static void
+ip_nat_free(ip_nat_conf_t *item)
+{
+  LWIP_ASSERT("item != NULL", item != NULL);
+  mem_free(item);
+}
+
+/** Add a new NAT entry
+ *
+ * @param new_entry pointer to a structure used to initialize the entry
+ * @return ERR_OK if succeeded
+ */
+err_t
+ip_nat_add(const ip_nat_entry_t *new_entry)
+{
+  err_t err = ERR_VAL;
+  ip_nat_conf_t *cur = ip_nat_cfg;
+  ip_nat_conf_t *ip_nat_cfg_new = ip_nat_alloc();
+  LWIP_ASSERT("new_entry != NULL", new_entry != NULL);
+
+  if (ip_nat_cfg_new != NULL) {
+    SMEMCPY(&ip_nat_cfg_new->entry, new_entry, sizeof(ip_nat_entry_t));
+    ip_nat_cfg_new->next = NULL;
+
+    ip_nat_dbg_dump_init(ip_nat_cfg_new);
+
+    if (ip_nat_cfg == NULL) {
+      ip_nat_cfg = ip_nat_cfg_new;
+    } else {
+      /* @todo: do we really need to enqueue the new entry at the end?? */
+      while (cur->next != NULL) {
+        cur = cur->next;
+      }
+      cur->next = ip_nat_cfg_new;
+    }
+    err = ERR_OK;
+  } else {
+    err = ERR_MEM;
+  }
+  return err;
+}
+
+/** Remove a NAT entry previously added by 'ip_nat_add()'.
+ *
+ * @param remove_entry describes the entry to remove
+ */
+void
+ip_nat_remove(const ip_nat_entry_t *remove_entry)
+{
+  ip_nat_conf_t *cur = ip_nat_cfg;
+  ip_nat_conf_t *next;
+  ip_nat_conf_t *previous = NULL;
+
+  while (cur != NULL) {
+    /* Remove the NAT interfaces */
+    if ((cur->entry.source_net.addr     == remove_entry->source_net.addr) &&
+        (cur->entry.source_netmask.addr == remove_entry->source_netmask.addr) &&
+        (cur->entry.dest_net.addr       == remove_entry->dest_net.addr) &&
+        (cur->entry.dest_netmask.addr   == remove_entry->dest_netmask.addr) &&
+        (cur->entry.out_if              == remove_entry->out_if) &&
+        (cur->entry.in_if               == remove_entry->in_if))
+    {
+      ip_nat_dbg_dump_remove(cur);
+
+      ip_nat_reset_state(cur);
+      next = cur->next;
+      if (cur == ip_nat_cfg) {
+        ip_nat_cfg = next;
+      } else {
+        LWIP_ASSERT("NULL != previous", NULL != previous);
+        previous->next = next;
+      }
+      /* free 'cur' or there will be a memory leak */
+      ip_nat_free(cur);
+      return;
+    } else {
+      previous = cur;
+      cur = cur->next;
+    }
+  }
+}
+
+/** Reset a NAT configured entry to be reused.
+ * Effectively calls IPNAT_ENTRY_RESET() on 'cfg'.
+ *
+ * @param cfg NAT entry to reset
+ */
+static void
+ip_nat_reset_state(ip_nat_conf_t *cfg)
+{
+  int i;
+
+  /* @todo: optimize this!!!
+     why do we search for it anyway, if we have the pointer??? */
+  for (i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_ICMP; i++) {
+    if(ip_nat_icmp_table[i].common.cfg == cfg) {
+      IPNAT_ENTRY_RESET(&ip_nat_icmp_table[i].common);
+    }
+  }
+  for (i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_TCP; i++) {
+    if(ip_nat_icmp_table[i].common.cfg == cfg) {
+      IPNAT_ENTRY_RESET(&ip_nat_tcp_table[i].common);
+    }
+  }
+  for (i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_UDP; i++) {
+    if(ip_nat_icmp_table[i].common.cfg == cfg) {
+      IPNAT_ENTRY_RESET(&ip_nat_udp_table[i].common);
+    }
+  }
+}
+
+/** Check if this packet should be routed or should be translated
+ *
+ * @param iphdr the IP header to check
+ * @return - a NAT entry if the packet shall be translated,
+ *         - NULL if the packet shall be routed normally
+ */
+static ip_nat_conf_t *
+ip_nat_shallnat(const struct ip_hdr *iphdr)
+{
+  ip_nat_conf_t *nat_config = ip_nat_cfg;
+
+  for (nat_config = ip_nat_cfg; nat_config != NULL; nat_config = nat_config->next) {
+      if (ip_addr_netcmp(&(iphdr->dest), &(nat_config->entry.dest_net),
+                       &(nat_config->entry.dest_netmask)) ||
+      ip_addr_netcmp(&(iphdr->src), &(nat_config->entry.source_net),
+                     &(nat_config->entry.source_netmask))) {
+        break;
+    }
+  }
+
+  return nat_config;
+}
+
+/** Check if the IP header can be hidden and if the remaining packet
+ * is long enough. p->payload is reset to the IP header on return.
+ *
+ * @param p received packet, p->payload pointing to IP header
+ * @param min_size minimum p->tot_len after hiding IP header
+ * @return a pointer to the next header (after IP header),
+ *         NULL if hiding IP header fails or the packet is too short
+ */
+static void*
+ip_nat_check_header(struct pbuf *p, u16_t min_size)
+{
+  void *ret = NULL;
+  struct ip_hdr  *iphdr = (struct ip_hdr*)p->payload;
+  s16_t iphdr_len = IPH_HL(iphdr) * 4;
+
+  if(!pbuf_header(p, -iphdr_len)) {
+    if(p->tot_len >= min_size) {
+      ret = p->payload;
+    }
+    /* Restore pbuf payload pointer from previous header check. */
+    pbuf_header(p, iphdr_len);
+  }
+  return ret;
+}
+
+/** Input processing: check if a received packet belongs to a NAT entry
+ * and if so, translated it and send it on.
+ *
+ * @param p received packet
+ * @return 1 if the packet has been consumed (it was a NAT packet),
+ *         0 if the packet has not been consumed (no NAT packet)
+ */
+u8_t
+ip_nat_input(struct pbuf *p)
+{
+  struct ip_hdr        *iphdr = (struct ip_hdr*)p->payload;
+  struct tcp_hdr       *tcphdr;
+  struct udp_hdr       *udphdr;
+  struct icmp_echo_hdr *icmphdr;
+  nat_entry_t           nat_entry;
+  err_t                 err;
+  u8_t                  consumed = 0;
+  int                   i;
+  struct pbuf          *q = NULL;
+
+  nat_entry.cmn = NULL;
+  ip_nat_dbg_dump("ip_nat_in: checking nat for", iphdr);
+
+  switch (IPH_PROTO(iphdr)) {
+    case IP_PROTO_TCP:
+      tcphdr = (struct tcp_hdr*)ip_nat_check_header(p, sizeof(struct tcp_hdr));
+      if (tcphdr == NULL) {
+        LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_input: short tcp packet (%" U16_F " bytes) discarded\n", p->tot_len));
+      } else {
+        nat_entry.tcp = ip_nat_tcp_lookup_incoming(iphdr, tcphdr);
+        if (nat_entry.tcp != NULL) {
+          /* Refresh TCP entry */
+          nat_entry.tcp->common.ttl = LWIP_NAT_DEFAULT_TTL_SECONDS;
+          tcphdr->dest = nat_entry.tcp->sport;
+          /* Adjust TCP checksum for changed destination port */
+          ip_nat_chksum_adjust((u8_t *)&(tcphdr->chksum),
+            (u8_t *)&(nat_entry.tcp->nport), 2, (u8_t *)&(tcphdr->dest), 2);
+          /* Adjust TCP checksum for changing dest IP address */
+          ip_nat_chksum_adjust((u8_t *)&(tcphdr->chksum),
+            (u8_t *)&(nat_entry.cmn->cfg->entry.out_if->ip_addr.addr), 4,
+            (u8_t *)&(nat_entry.cmn->source.addr), 4);
+
+          consumed = 1;
+        }
+      }
+      break;
+
+    case IP_PROTO_UDP:
+      udphdr = (struct udp_hdr *)ip_nat_check_header(p, sizeof(struct udp_hdr));
+      if (udphdr == NULL) {
+        LWIP_DEBUGF(LWIP_NAT_DEBUG,
+          ("ip_nat_input: short udp packet (%" U16_F " bytes) discarded\n",
+          p->tot_len));
+      } else {
+        nat_entry.udp = ip_nat_udp_lookup_incoming(iphdr, udphdr);
+        if (nat_entry.udp != NULL) {
+          /* Refresh UDP entry */
+          nat_entry.udp->common.ttl = LWIP_NAT_DEFAULT_TTL_SECONDS;
+          udphdr->dest = nat_entry.udp->sport;
+          /* Adjust UDP checksum for changed destination port */
+          ip_nat_chksum_adjust((u8_t *)&(udphdr->chksum),
+            (u8_t *)&(nat_entry.udp->nport), 2, (u8_t *)&(udphdr->dest), 2);
+          /* Adjust UDP checksum for changing dest IP address */
+          ip_nat_chksum_adjust((u8_t *)&(udphdr->chksum),
+            (u8_t *)&(nat_entry.cmn->cfg->entry.out_if->ip_addr.addr), 4,
+            (u8_t *)&(nat_entry.cmn->source.addr), 4);
+
+          consumed = 1;
+        }
+      }
+      break;
+
+    case IP_PROTO_ICMP:
+      icmphdr = (struct icmp_echo_hdr *)ip_nat_check_header(p, sizeof(struct icmp_echo_hdr));
+      if (icmphdr == NULL) {
+        LWIP_DEBUGF(LWIP_NAT_DEBUG,
+          ("ip_nat_out: short icmp echo reply packet (%" U16_F " bytes) discarded\n",
+          p->tot_len));
+      } else {
+        if (ICMP_ER == ICMPH_TYPE(icmphdr)) {
+          for (i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_ICMP; i++) {
+            nat_entry.icmp = &ip_nat_icmp_table[i];
+            if ((nat_entry.icmp->common.ttl) &&
+                (iphdr->src.addr == nat_entry.icmp->common.dest.addr) &&
+                (nat_entry.icmp->id == icmphdr->id) &&
+                (nat_entry.icmp->seqno == icmphdr->seqno)) {
+              ip_nat_dbg_dump_icmp_nat_entry("found existing nat entry: ", nat_entry.icmp);
+              consumed = 1;
+              IPNAT_ENTRY_RESET(nat_entry.cmn);
+              break;
+            }
+          }
+        }
+      }
+      break;
+
+    default:
+      break;
+  }
+
+  if(consumed) {
+    /* packet consumed, send it out on in_if */
+    struct netif *in_if;
+
+    /* check if the pbuf has room for link headers */
+    if (pbuf_header(p, PBUF_LINK_HLEN)) {
+      /* pbuf has no room for link headers, allocate an extra pbuf */
+      q = pbuf_alloc(PBUF_LINK, 0, PBUF_RAM);
+      if (q == NULL) {
+        LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_input: no pbuf for outgoing header\n"));
+        // rt_kprintf("ip_nat_input: no pbuf for outgoing header\n");
+        /* @todo: stats? */
+        pbuf_free(p);
+        p = NULL;
+        return 1;
+      } else {
+        pbuf_cat(q, p);
+      }
+    } else {
+      /* restore p->payload to IP header */
+      if (pbuf_header(p, -PBUF_LINK_HLEN)) {
+        LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_input: restoring header failed\n"));
+        // rt_kprintf("ip_nat_input: restoring header failed\n");
+        /* @todo: stats? */
+        pbuf_free(p);
+        p = NULL;
+        return 1;
+      }
+      else q = p;
+    }
+    /* if we come here, q is the pbuf to send (either points to p or to a chain) */
+    in_if = nat_entry.cmn->cfg->entry.in_if;
+    iphdr->dest.addr = nat_entry.cmn->source.addr;
+    ip_nat_chksum_adjust((u8_t *) & IPH_CHKSUM(iphdr),
+      (u8_t *) & (nat_entry.cmn->cfg->entry.out_if->ip_addr.addr), 4,
+      (u8_t *) & (iphdr->dest.addr), 4);
+
+    ip_nat_dbg_dump("ip_nat_input: packet back to source after nat: ", iphdr);
+    LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_input: sending packet on interface ("));
+    ip_nat_dbg_dump_ip(&(in_if->ip_addr));
+    LWIP_DEBUGF(LWIP_NAT_DEBUG, (")\n"));
+
+    err = in_if->output(in_if, q, (ip_addr_t *)&(iphdr->dest));
+    if(err != ERR_OK) {
+      LWIP_DEBUGF(LWIP_NAT_DEBUG,
+        ("ip_nat_input: failed to send rewritten packet. link layer returned %d\n",
+        err));
+      // rt_kprintf("ip_nat_input: failed to send rewritten packet. link layer returned %d\n", err);
+    }
+    /* now that q (and/or p) is sent (or not), give up the reference to it
+       this frees the input pbuf (p) as we have consumed it. */
+    pbuf_free(q);
+  }
+  return consumed;
+}
+
+/** Check if one NAT entry timed out */
+static void
+ip_nat_check_timeout(ip_nat_entry_common_t *nat_entry)
+{
+  if(nat_entry->ttl > 0) {
+    if(nat_entry->ttl != LWIP_NAT_TTL_INFINITE) {
+      /* this is not a 'no-timeout' entry */
+      if(nat_entry->ttl > LWIP_NAT_TMR_INTERVAL_SEC) {
+        nat_entry->ttl -= LWIP_NAT_TMR_INTERVAL_SEC;
+      } else {
+        nat_entry->ttl = 0;
+      }
+    }
+  }
+}
+
+/** The NAT timer function, to be called at an interval of
+ * LWIP_NAT_TMR_INTERVAL_SEC seconds.
+ */
+void
+ip_nat_tmr(void)
+{
+  int i;
+
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_tmr: removing old entries\n"));
+
+  for(i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_ICMP; i++) {
+    ip_nat_check_timeout((ip_nat_entry_common_t *) & ip_nat_icmp_table[i]);
+  }
+  for(i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_TCP; i++) {
+    ip_nat_check_timeout((ip_nat_entry_common_t *) & ip_nat_tcp_table[i]);
+  }
+  for(i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_UDP; i++) {
+    ip_nat_check_timeout((ip_nat_entry_common_t *) & ip_nat_udp_table[i]);
+  }
+}
+
+/** Vheck if we want to perform NAT with this packet. If so, send it out on
+ * the correct interface.
+ *
+ * @param p the packet to test/send
+ * @return 1: the packet has been sent using NAT,
+ *         0: the packet did not belong to a NAT entry
+ */
+u8_t
+ip_nat_out(struct pbuf *p)
+{
+  u8_t                  sent = 0;
+  err_t                 err;
+  struct ip_hdr        *iphdr = p->payload;
+  struct icmp_echo_hdr *icmphdr;
+  struct tcp_hdr       *tcphdr;
+  struct udp_hdr       *udphdr;
+  ip_nat_conf_t        *nat_config;
+  nat_entry_t           nat_entry;
+  int             i;
+
+  nat_entry.cmn = NULL;
+
+  ip_nat_dbg_dump("ip_nat_out: checking nat for", iphdr);
+
+  /* Check if this packet should be routed or should be translated */
+  nat_config = ip_nat_shallnat(iphdr);
+  if (nat_config != NULL ) {
+    if (nat_config->entry.out_if == NULL) {
+      LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_out: no external interface for nat table entry\n"));
+    } else {
+      switch (IPH_PROTO(iphdr))
+      {
+      case IP_PROTO_TCP:
+        tcphdr = (struct tcp_hdr *)ip_nat_check_header(p, sizeof(struct tcp_hdr));
+        if (tcphdr == NULL) {
+          LWIP_DEBUGF(LWIP_NAT_DEBUG,
+            ("ip_nat_out: short tcp packet (%" U16_F " bytes) discarded\n", p->tot_len));
+        } else {
+          nat_entry.tcp = ip_nat_tcp_lookup_outgoing(nat_config, iphdr, tcphdr, 1);
+          if (nat_entry.tcp != NULL) {
+            /* Adjust TCP checksum for changing source port */
+            tcphdr->src = nat_entry.tcp->nport;
+            ip_nat_chksum_adjust((u8_t *)&(tcphdr->chksum),
+              (u8_t *)&(nat_entry.tcp->sport), 2, (u8_t *)&(tcphdr->src), 2);
+            /* Adjust TCP checksum for changing source IP address */
+            ip_nat_chksum_adjust((u8_t *)&(tcphdr->chksum),
+              (u8_t *)&(nat_entry.cmn->source.addr), 4,
+              (u8_t *)&(nat_entry.cmn->cfg->entry.out_if->ip_addr.addr), 4);
+          }
+        }
+        break;
+
+      case IP_PROTO_UDP:
+        udphdr = (struct udp_hdr *)ip_nat_check_header(p, sizeof(struct udp_hdr));
+        if (udphdr == NULL) {
+          LWIP_DEBUGF(LWIP_NAT_DEBUG,
+            ("ip_nat_out: short udp packet (%" U16_F " bytes) discarded\n", p->tot_len));
+        } else {
+          nat_entry.udp = ip_nat_udp_lookup_outgoing(nat_config, iphdr, udphdr, 1);
+          if (nat_entry.udp != NULL) {
+            /* Adjust UDP checksum for changing source port */
+            udphdr->src = nat_entry.udp->nport;
+            ip_nat_chksum_adjust((u8_t *)&(udphdr->chksum),
+              (u8_t *)&(nat_entry.udp->sport), 2, (u8_t *) & (udphdr->src), 2);
+            /* Adjust UDP checksum for changing source IP address */
+            ip_nat_chksum_adjust((u8_t *)&(udphdr->chksum),
+              (u8_t *)&(nat_entry.cmn->source.addr), 4,
+              (u8_t *)&(nat_entry.cmn->cfg->entry.out_if->ip_addr.addr), 4);
+          }
+        }
+        break;
+
+      case IP_PROTO_ICMP:
+        icmphdr = (struct icmp_echo_hdr *)ip_nat_check_header(p, sizeof(struct icmp_echo_hdr));
+        if(icmphdr == NULL) {
+          LWIP_DEBUGF(LWIP_NAT_DEBUG,
+            ("ip_nat_out: short icmp echo packet (%" U16_F " bytes) discarded\n", p->tot_len));
+        } else {
+          if (ICMPH_TYPE(icmphdr) == ICMP_ECHO) {
+            for (i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_ICMP; i++) {
+              if (!ip_nat_icmp_table[i].common.ttl) {
+                nat_entry.icmp = &ip_nat_icmp_table[i];
+                ip_nat_cmn_init(nat_config, iphdr, nat_entry.cmn);
+                nat_entry.icmp->id = icmphdr->id;
+                nat_entry.icmp->seqno = icmphdr->seqno;
+                ip_nat_dbg_dump_icmp_nat_entry(" ip_nat_out: created new NAT entry ", nat_entry.icmp);
+                break;
+              }
+            }
+            if (NULL == nat_entry.icmp)
+            {
+              LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_out: no more NAT entries for ICMP available\n"));
+            }
+          }
+        }
+        break;
+      default:
+        break;
+      }
+
+      if (nat_entry.cmn != NULL) {
+        struct netif *out_if = nat_entry.cmn->cfg->entry.out_if;
+        /* Exchange the IP source address with the address of the interface
+        * where the packet will be sent.
+        */
+        /* @todo: check nat_config->entry.out_if agains nat_entry.cmn->cfg->entry.out_if */
+        iphdr->src.addr = nat_config->entry.out_if->ip_addr.addr;
+        ip_nat_chksum_adjust((u8_t *) & IPH_CHKSUM(iphdr),
+          (u8_t *) & (nat_entry.cmn->source.addr), 4, (u8_t *) & iphdr->src.addr, 4);
+
+        ip_nat_dbg_dump("ip_nat_out: rewritten packet", iphdr);
+        LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_out: sending packet on interface ("));
+        ip_nat_dbg_dump_ip(&(out_if->ip_addr));
+        LWIP_DEBUGF(LWIP_NAT_DEBUG, (")\n"));
+
+        err = out_if->output(out_if, p, (ip_addr_t *)&(iphdr->dest));
+        if (err != ERR_OK) {
+          LWIP_DEBUGF(LWIP_NAT_DEBUG,
+            ("ip_nat_out: failed to send rewritten packet. link layer returned %d\n", err));
+          // rt_kprintf("ip_nat_out: failed to send rewritten packet. link layer returned %d\n", err);
+        } else {
+          sent = 1;
+        }
+      }
+    }
+  }
+
+  return sent;
+}
+
+/** Initialize common parts of a NAT entry
+ *
+ * @param nat_config NAT config entry
+ * @param iphdr IP header from which to initialize the entry
+ * @param nat_entry entry to initialize
+ */
+static void
+ip_nat_cmn_init(ip_nat_conf_t *nat_config, const struct ip_hdr *iphdr, ip_nat_entry_common_t *nat_entry)
+{
+  LWIP_ASSERT("NULL != nat_entry", NULL != nat_entry);
+  LWIP_ASSERT("NULL != nat_config", NULL != nat_config);
+  LWIP_ASSERT("NULL != iphdr", NULL != iphdr);
+  nat_entry->cfg = nat_config;
+  nat_entry->dest = *((ip_addr_t *)&iphdr->dest);
+  nat_entry->source = *((ip_addr_t *)&iphdr->src);
+  nat_entry->ttl = LWIP_NAT_DEFAULT_TTL_SECONDS;
+}
+
+/**
+ * This function checks for incoming packets if we already have a NAT entry.
+ * If yes a pointer to the NAT entry is returned. Otherwise NULL.
+ *
+ * @param nat_config NAT configuration.
+ * @param iphdr The IP header.
+ * @param udphdr The UDP header.
+ * @return A pointer to an existing NAT entry or
+ *         NULL if none is found.
+ */
+static ip_nat_entries_udp_t *
+ip_nat_udp_lookup_incoming(const struct ip_hdr *iphdr, const struct udp_hdr *udphdr)
+{
+  int i;
+  ip_nat_entries_udp_t *nat_entry = NULL;
+
+  for (i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_UDP; i++) {
+    if (ip_nat_udp_table[i].common.ttl) {
+      if ((iphdr->src.addr == ip_nat_udp_table[i].common.dest.addr) &&
+          (udphdr->src == ip_nat_udp_table[i].dport) &&
+          (udphdr->dest == ip_nat_udp_table[i].nport)) {
+        nat_entry = &ip_nat_udp_table[i];
+        ip_nat_dbg_dump_udp_nat_entry("ip_nat_udp_lookup_incoming: found existing nat entry: ",
+                                      nat_entry);
+        break;
+      }
+    }
+  }
+  return nat_entry;
+}
+
+/**
+ * This function checks if we already have a NAT entry for this UDP connection.
+ * If yes the a pointer to this NAT entry is returned.
+ *
+ * @param iphdr The IP header.
+ * @param udphdr The UDP header.
+ * @param allocate If no existing NAT entry is found and this flag is true
+ *        a NAT entry is allocated.
+ */
+static ip_nat_entries_udp_t *
+ip_nat_udp_lookup_outgoing(ip_nat_conf_t *nat_config, const struct ip_hdr *iphdr,
+                           const struct udp_hdr *udphdr, u8_t allocate)
+{
+  int i;
+  nat_entry_t nat_entry;
+  int last_free = -1;
+
+  nat_entry.cmn = NULL;
+  for (i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_UDP; i++) {
+    if (ip_nat_udp_table[i].common.ttl) {
+      if ((iphdr->src.addr == ip_nat_udp_table[i].common.source.addr) &&
+          (iphdr->dest.addr == ip_nat_udp_table[i].common.dest.addr) &&
+          (udphdr->src == ip_nat_udp_table[i].sport) &&
+          (udphdr->dest == ip_nat_udp_table[i].dport)) {
+        nat_entry.udp = &ip_nat_udp_table[i];
+
+        ip_nat_dbg_dump_udp_nat_entry("ip_nat_udp_lookup_outgoing: found existing nat entry: ",
+                                      nat_entry.udp);
+        break;
+      }
+    } else {
+        last_free = i;
+    }
+  }
+  if (nat_entry.cmn == NULL) {
+    if (allocate) {
+      if (last_free != -1) {
+        nat_entry.udp = &ip_nat_udp_table[last_free];
+        nat_entry.udp->nport = htons((u16_t) (LWIP_NAT_DEFAULT_UDP_SOURCE_PORT + i));
+        nat_entry.udp->sport = udphdr->src;
+        nat_entry.udp->dport = udphdr->dest;
+        ip_nat_cmn_init(nat_config, iphdr, nat_entry.cmn);
+
+        ip_nat_dbg_dump_udp_nat_entry("ip_nat_udp_lookup_outgoing: created new nat entry: ",
+                                      nat_entry.udp);
+      } else {
+        LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_udp_lookup_outgoing: no more NAT entries available\n"));
+        // rt_kprintf("ip_nat_udp_lookup_outgoing: no more NAT entries available\n");
+      }
+    }
+  }
+  return nat_entry.udp;
+}
+
+/**
+ * This function checks for incoming packets if we already have a NAT entry.
+ * If yes a pointer to the NAT entry is returned. Otherwise NULL.
+ *
+ * @param nat_config NAT configuration.
+ * @param iphdr The IP header.
+ * @param tcphdr The TCP header.
+ * @return A pointer to an existing NAT entry or NULL if none is found.
+ */
+static ip_nat_entries_tcp_t *
+ip_nat_tcp_lookup_incoming(const struct ip_hdr *iphdr, const struct tcp_hdr *tcphdr)
+{
+  int i;
+  ip_nat_entries_tcp_t *nat_entry = NULL;
+
+  for (i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_TCP; i++) {
+    if (ip_nat_tcp_table[i].common.ttl) {
+      if ((iphdr->src.addr == ip_nat_tcp_table[i].common.dest.addr) &&
+          (tcphdr->src == ip_nat_tcp_table[i].dport) &&
+          (tcphdr->dest == ip_nat_tcp_table[i].nport)) {
+        nat_entry = &ip_nat_tcp_table[i];
+
+        ip_nat_dbg_dump_tcp_nat_entry("ip_nat_tcp_lookup_incoming: found existing nat entry: ",
+                                      nat_entry);
+        break;
+      }
+    }
+  }
+  return nat_entry;
+}
+
+/**
+ * This function checks if we already have a NAT entry for this TCP connection.
+ * If yes the a pointer to this NAT entry is returned.
+ *
+ * @param iphdr The IP header.
+ * @param tcphdr The TCP header.
+ * @param allocate If no existing NAT entry is found and this flag is true
+ *   a NAT entry is allocated.
+ */
+static ip_nat_entries_tcp_t *
+ip_nat_tcp_lookup_outgoing(ip_nat_conf_t *nat_config, const struct ip_hdr *iphdr,
+                           const struct tcp_hdr *tcphdr, u8_t allocate)
+{
+  int i;
+  nat_entry_t nat_entry;
+  int last_free = -1;
+
+  nat_entry.cmn = NULL;
+  for (i = 0; i < LWIP_NAT_DEFAULT_STATE_TABLES_TCP; i++) {
+    if (ip_nat_tcp_table[i].common.ttl) {
+      if ((iphdr->src.addr == ip_nat_tcp_table[i].common.source.addr) &&
+          (iphdr->dest.addr == ip_nat_tcp_table[i].common.dest.addr) &&
+          (tcphdr->src == ip_nat_tcp_table[i].sport) &&
+          (tcphdr->dest == ip_nat_tcp_table[i].dport)) {
+        nat_entry.tcp = &ip_nat_tcp_table[i];
+
+        ip_nat_dbg_dump_tcp_nat_entry("ip_nat_tcp_lookup_outgoing: found existing nat entry: ",
+                                      nat_entry.tcp);
+        break;
+      }
+    } else {
+        last_free = i;
+    }
+  }
+  if (nat_entry.cmn == NULL) {
+    if (allocate) {
+      if (last_free != -1) {
+        nat_entry.tcp = &ip_nat_tcp_table[last_free];
+        nat_entry.tcp->nport = htons((u16_t) (LWIP_NAT_DEFAULT_TCP_SOURCE_PORT + i));
+        nat_entry.tcp->sport = tcphdr->src;
+        nat_entry.tcp->dport = tcphdr->dest;
+        ip_nat_cmn_init(nat_config, iphdr, nat_entry.cmn);
+
+        ip_nat_dbg_dump_tcp_nat_entry("ip_nat_tcp_lookup_outgoing: created new nat entry: ",
+                                      nat_entry.tcp);
+      } else {
+        LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_udp_lookup_outgoing: no more NAT entries available\n"));
+        // rt_kprintf("ip_nat_udp_lookup_outgoing: no more NAT entries available\n");
+      }
+    }
+  }
+  return nat_entry.tcp;
+}
+
+/** Adjusts the checksum of a NAT'ed packet without having to completely recalculate it
+ * @todo: verify this works for little- and big-endian
+ *
+ * @param chksum points to the chksum in the packet
+ * @param optr points to the old data in the packet
+ * @param olen length of old data
+ * @param nptr points to the new data in the packet
+ * @param nlen length of new data
+ */
+static void
+ip_nat_chksum_adjust(u8_t *chksum, const u8_t *optr, s16_t olen, const u8_t *nptr, s16_t nlen)
+{
+  s32_t x, oldval, newval;
+
+  LWIP_ASSERT("NULL != chksum", NULL != chksum);
+  LWIP_ASSERT("NULL != optr", NULL != optr);
+  LWIP_ASSERT("NULL != nptr", NULL != nptr);
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_chksum_adjust: chksum=%p, optr=%p, olen=%" U16_F ", nptr=%p, nlen=%" U16_F "\n",
+    chksum, optr, olen, nptr, nlen));
+  x = chksum[0] * 256 + chksum[1];
+  x = ~x & 0xFFFF;
+  while (olen) {
+    oldval = optr[0] * 256 + optr[1];
+    optr += 2;
+    x -= oldval & 0xffff;
+    if (x <= 0) {
+      x--;
+      x &= 0xffff;
+    }
+    olen -= 2;
+  }
+  while (nlen) {
+    newval = nptr[0] * 256 + nptr[1];
+    nptr += 2;
+    x += newval & 0xffff;
+    if (x & 0x10000) {
+      x++;
+      x &= 0xffff;
+    }
+    nlen -= 2;
+  }
+  x = ~x & 0xFFFF;
+  chksum[0] = x / 256;
+  chksum[1] = x & 0xff;
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_chksum_adjust: chksum = 0x%x\n", *((u16_t *) chksum)));
+}
+
+#if defined(LWIP_DEBUG) && (LWIP_NAT_DEBUG & LWIP_DBG_ON)
+/**
+ * This function dumps an IP address
+ *
+ * @param addr IP address
+ */
+static void
+ip_nat_dbg_dump_ip(const ip_addr_t *addr)
+{
+  LWIP_ASSERT("NULL != addr", NULL != addr);
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("%" U16_F ".%" U16_F ".%" U16_F ".%" U16_F,
+    ip4_addr1(addr), ip4_addr2(addr), ip4_addr3(addr), ip4_addr4(addr)));
+}
+
+/**
+ * This function dumps an IP header
+ *
+ * @param msg a message to print
+ * @param iphdr IP header
+ */
+static void
+ip_nat_dbg_dump(const char *msg, const struct ip_hdr *iphdr)
+{
+  LWIP_ASSERT("NULL != msg", NULL != msg);
+  LWIP_ASSERT("NULL != iphdr", NULL != iphdr);
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("%s: IP: (", msg));
+  ip_nat_dbg_dump_ip((ip_addr_t *)&(iphdr->src));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (" --> "));
+  ip_nat_dbg_dump_ip((ip_addr_t *)&(iphdr->dest));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (" id=%" U16_F ", chksum=%" U16_F ")\n",
+    ntohs(IPH_ID(iphdr)), ntohs(IPH_CHKSUM(iphdr))));
+}
+
+/**
+ * This function dumps an ICMP echo reply/recho request nat entry.
+ *
+ * @param msg a message to print
+ * @param nat_entry the ICMP NAT entry to print
+ */
+static void
+ip_nat_dbg_dump_icmp_nat_entry(const char *msg, const ip_nat_entries_icmp_t *nat_entry)
+{
+  LWIP_ASSERT("NULL != msg", NULL != msg);
+  LWIP_ASSERT("NULL != nat_entry", NULL != nat_entry);
+  LWIP_ASSERT("NULL != nat_entry->common.cfg", NULL != nat_entry->common.cfg);
+  LWIP_ASSERT("NULL != nat_entry->common.cfg->entry.out_if",
+    NULL != nat_entry->common.cfg->entry.out_if);
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("%s", msg));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ICMP : ("));
+  ip_nat_dbg_dump_ip(&(nat_entry->common.source));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (" --> "));
+  ip_nat_dbg_dump_ip(&(nat_entry->common.dest));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (" id=%" U16_F, ntohs(nat_entry->id)));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (", seq=%" U16_F, ntohs(nat_entry->seqno)));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (") mapped at ("));
+  ip_nat_dbg_dump_ip(&(nat_entry->common.cfg->entry.out_if->ip_addr));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (" --> "));
+  ip_nat_dbg_dump_ip(&(nat_entry->common.dest));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (" id=%" U16_F, ntohs(nat_entry->id)));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (", seq=%" U16_F, ntohs(nat_entry->seqno)));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (")\n"));
+}
+
+/**
+ * This function dumps an TCP nat entry.
+ *
+ * @param msg a message to print
+ * @param nat_entry the TCP NAT entry to print
+ */
+static void
+ip_nat_dbg_dump_tcp_nat_entry(const char *msg, const ip_nat_entries_tcp_t *nat_entry)
+{
+  LWIP_ASSERT("NULL != msg", NULL != msg);
+  LWIP_ASSERT("NULL != nat_entry", NULL != nat_entry);
+  LWIP_ASSERT("NULL != nat_entry->common.cfg", NULL != nat_entry->common.cfg);
+  LWIP_ASSERT("NULL != nat_entry->common.cfg->entry.out_if",
+    NULL != nat_entry->common.cfg->entry.out_if);
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("%s", msg));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("TCP : ("));
+  ip_nat_dbg_dump_ip(&(nat_entry->common.source));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (":%" U16_F, ntohs(nat_entry->sport)));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (" --> "));
+  ip_nat_dbg_dump_ip(&(nat_entry->common.dest));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (":%" U16_F, ntohs(nat_entry->dport)));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (") mapped at ("));
+  ip_nat_dbg_dump_ip(&(nat_entry->common.cfg->entry.out_if->ip_addr));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (":%" U16_F, ntohs(nat_entry->nport)));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (" --> "));
+  ip_nat_dbg_dump_ip(&(nat_entry->common.dest));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (":%" U16_F, ntohs(nat_entry->dport)));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (")\n"));
+}
+
+/**
+ * This function dumps a UDP NAT entry.
+ *
+ * @param msg a message to print
+ * @param nat_entry the UDP NAT entry to print
+ */
+static void
+ip_nat_dbg_dump_udp_nat_entry(const char *msg, const ip_nat_entries_udp_t *nat_entry)
+{
+  LWIP_ASSERT("NULL != msg", NULL != msg);
+  LWIP_ASSERT("NULL != nat_entry", NULL != nat_entry);
+  LWIP_ASSERT("NULL != nat_entry->common.cfg", NULL != nat_entry->common.cfg);
+  LWIP_ASSERT("NULL != nat_entry->common.cfg->entry.out_if",
+    NULL != nat_entry->common.cfg->entry.out_if);
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("%s", msg));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("UDP : ("));
+  ip_nat_dbg_dump_ip(&(nat_entry->common.source));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (":%" U16_F, ntohs(nat_entry->sport)));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (" --> "));
+  ip_nat_dbg_dump_ip(&(nat_entry->common.dest));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (":%" U16_F, ntohs(nat_entry->dport)));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (") mapped at ("));
+  ip_nat_dbg_dump_ip(&(nat_entry->common.cfg->entry.out_if->ip_addr));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (":%" U16_F, ntohs(nat_entry->nport)));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (" --> "));
+  ip_nat_dbg_dump_ip(&(nat_entry->common.dest));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (":%" U16_F, ntohs(nat_entry->dport)));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (")\n"));
+}
+
+/** Prints some info when creating a new NAT entry */
+static void
+ip_nat_dbg_dump_init(ip_nat_conf_t *ip_nat_cfg_new)
+{
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_init: added new NAT interface\n"));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_init:   "));
+  ip_nat_dbg_dump_ip(&(ip_nat_cfg_new->entry.source_net));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("/"));
+  ip_nat_dbg_dump_ip(&(ip_nat_cfg_new->entry.source_netmask));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("@"));
+  ip_nat_dbg_dump_ip(&(ip_nat_cfg_new->entry.in_if->ip_addr));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (" --> "));
+  ip_nat_dbg_dump_ip(&(ip_nat_cfg_new->entry.dest_net));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("/"));
+  ip_nat_dbg_dump_ip(&(ip_nat_cfg_new->entry.dest_netmask));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("@"));
+  ip_nat_dbg_dump_ip(&(ip_nat_cfg_new->entry.out_if->ip_addr));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("\n"));
+}
+
+/** Prints some info when removing a NAT entry */
+static void
+ip_nat_dbg_dump_remove(ip_nat_conf_t *cur)
+{
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_remove: removing existing NAT interface\n"));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("ip_nat_remove:   "));
+  ip_nat_dbg_dump_ip(&(cur->entry.source_net));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("/"));
+  ip_nat_dbg_dump_ip(&(cur->entry.source_netmask));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("@"));
+  ip_nat_dbg_dump_ip(&(cur->entry.in_if->ip_addr));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, (" --> "));
+  ip_nat_dbg_dump_ip(&(cur->entry.dest_net));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("/"));
+  ip_nat_dbg_dump_ip(&(cur->entry.dest_netmask));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("@"));
+  ip_nat_dbg_dump_ip(&(cur->entry.out_if->ip_addr));
+  LWIP_DEBUGF(LWIP_NAT_DEBUG, ("\n"));
+}
+#endif /* defined(LWIP_DEBUG) && (LWIP_NAT_DEBUG & LWIP_DBG_ON) */
+
+#endif /* IP_NAT */
diff --git a/components/net/lwip_nat/ipv4_nat.h b/components/net/lwip_nat/ipv4_nat.h
new file mode 100644
index 0000000000..e369c781da
--- /dev/null
+++ b/components/net/lwip_nat/ipv4_nat.h
@@ -0,0 +1,103 @@
+/**
+ * NAT - NAT implementation for lwIP supporting TCP/UDP and ICMP.
+ * Copyright (c) 2009 Christian Walter, ?Embedded Solutions, Vienna 2009.
+ *
+ * Copyright (c) 2010 lwIP project ;-)
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
+ * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
+ * OF SUCH DAMAGE.
+ *
+ * This file is part of the lwIP TCP/IP stack.
+ */
+
+/*
+ * File      : ipv4_nat.h
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2015, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2015-01-26     Hichard      porting to RT-Thread
+ * 2015-01-27     Bernard      code cleanup for lwIP in RT-Thread
+ */
+
+#ifndef __LWIP_NAT_H__
+#define __LWIP_NAT_H__
+
+#include <rtthread.h>
+
+#ifdef LWIP_USING_NAT
+
+#include "lwip/err.h"
+#include "lwip/ip_addr.h"
+#include "lwip/opt.h"
+
+/** Timer interval at which to call ip_nat_tmr() */
+#define LWIP_NAT_TMR_INTERVAL_SEC        (30*1000)
+
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+struct netif;
+struct pbuf;
+
+typedef struct ip_nat_entry
+{
+  ip_addr_t    source_net;
+  ip_addr_t    source_netmask;
+  ip_addr_t    dest_net;
+  ip_addr_t    dest_netmask;
+  struct netif *out_if;
+  struct netif *in_if;
+} ip_nat_entry_t;
+
+void  ip_nat_init(void);
+void  ip_nat_tmr(void);
+u8_t  ip_nat_input(struct pbuf *p);
+u8_t  ip_nat_out(struct pbuf *p);
+
+err_t ip_nat_add(const ip_nat_entry_t *new_entry);
+void  ip_nat_remove(const ip_nat_entry_t *remove_entry);
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* IP_NAT */
+
+#endif /* __LWIP_NAT_H__ */