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/**
* \file
*
* \brief TWI Master Mode management
*
* Copyright (c) 2010-2015 Atmel Corporation. All rights reserved.
*
* \asf_license_start
*
* \page License
*
* 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 Atmel may not be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* 4. This software may only be redistributed and used in connection with an
* Atmel microcontroller product.
*
* THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
* EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL 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.
*
* \asf_license_stop
*
*/
/*
* Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a>
*/
#ifndef TWI_MASTER_H_INCLUDED
#define TWI_MASTER_H_INCLUDED
#include <compiler.h>
#if (SAM4L)
# include "sam_twim/twi_master.h"
#elif (SAM3S || SAM3U || SAM3N || SAM3XA || SAM4S || SAM4E || SAM4N || SAM4C || SAMG || SAM4CP || SAM4CM)
# include "sam_twi/twi_master.h"
#elif XMEGA
# include "xmega_twi/twi_master.h"
#elif MEGA_RF
# include "megarf_twi/twi_master.h"
#elif UC3
# if (defined AVR32_TWI)
# include "uc3_twi/twi_master.h"
# else
# include "uc3_twim/twi_master.h"
# endif
#else
# error Unsupported chip type
#endif
/**
*
* \defgroup twi_group Two Wire-interface(TWI)
*
* This is the common API for TWIs. Additional features are available
* in the documentation of the specific modules.
*
* See \ref twi_quickstart.
*
* \section twi_group_platform Platform Dependencies
*
* The TWI API is partially chip- or platform-specific. While all
* platforms provide mostly the same functionality, there are some
* variations around how different bus types and clock tree structures
* are handled.
*
* The following functions are available on all platforms, but there may
* be variations in the function signature (i.e. parameters) and
* behaviour. These functions are typically called by platform-specific
* parts of drivers, and applications that aren't intended to be
* portable:
* - Master TWI Module initialization
* \code status_code_t twi_master_setup(*twi_module_pointer, twi_master_options_t *opt) \endcode
* - Enables TWI Module
* \code void twi_master_enable(*twi_module_pointer) \endcode
* - Disables TWI Module
* \code void twi_master_disable(*twi_module_pointer) \endcode
* - Read data from a slave device
* \code status_code_t twi_master_read(*twi_module_pointer, twi_package_t *package) \endcode
* - Write data from to a slave device
* \code status_code_t twi_master_write(*twi_module_pointer, twi_package_t *package) \endcode
*
* @{
*/
/**
* \typedef twi_master_t
* This type can be used independently to refer to TWI master module for the
* architecture used. It refers to the correct type definition for the
* architecture, ie. TWI_t* for XMEGA or avr32_twim_t* for UC3
*/
//! @}
/**
* \page twi_quickstart Quickstart guide for Common service TWI
*
* This is the quickstart guide for the \ref twi_group "Common service TWI",
* with step-by-step instructions on how to configure and use the driver in a
* selection of use cases.
*
* The use cases contain several code fragments. The code fragments in the
* steps for setup can be copied into a custom initialization function, while
* the steps for usage can be copied into, e.g., the main application function.
*
* \section twi_basic_use_case Basic use case
* In the most basic use case, the TWI module is configured for
* - Master operation
* - addressing one slave device of the bus at address 0x50
* - TWI clock of 50kHz
* - polled read/write handling
*
* \section twi_basic_use_case_setup Setup steps
* \subsection twi_basic_use_case_setup_code Example code
* Add to your application C-file:
* \code
void twi_init(void)
{
twi_master_options_t opt = {
.speed = 50000,
.chip = 0x50
};
twi_master_setup(&TWIM0, &opt);
}
\endcode
*
* \subsection twi_basic_use_case_setup_flow Workflow
* -# Ensure that board_init() has configured selected I/Os for TWI function.
* -# Ensure that \ref conf_twim.h is present for the driver.
* - \note This file is only for the driver and should not be included by the
* user.
* -# Define and initialize config structs for TWI module in your TWI initialization
* function:
* - \code
twi_master_options_t opt = {
.speed = 50000,
.chip = 0x50
}; \endcode
* - field \ref speed sets the baudrate of the TWI bus
* - field \ref chip sets the address of the slave device you want to communicate with
* -# Call twi_master_setup and optionally check its return code
* - \note The config structs can be reused for other TWI modules
* after this step. Simply reconfigure and write to others modules.
*
* \section twi_basic_use_case_usage Usage steps
* \subsection twi_basic_use_case_usage_code_writing Example code : Writing to a slave device
* Use in application C-file:
* \code
const uint8_t test_pattern[] = {0x55,0xA5,0x5A,0x77,0x99};
twi_package_t packet_write = {
.addr = EEPROM_MEM_ADDR, // TWI slave memory address data
.addr_length = sizeof (uint16_t), // TWI slave memory address data size
.chip = EEPROM_BUS_ADDR, // TWI slave bus address
.buffer = (void *)test_pattern, // transfer data source buffer
.length = sizeof(test_pattern) // transfer data size (bytes)
};
while (twi_master_write(&TWIM0, &packet_write) != TWI_SUCCESS);
\endcode
*
* \subsection twi_basic_use_case_usage_flow Workflow
* -# Prepare the data you want to send to the slave device:
* - \code const uint8_t test_pattern[] = {0x55,0xA5,0x5A,0x77,0x99}; \endcode
* -# Prepare a twi_package_t structure
* \code twi_package_t packet_write; \endcode
* Fill all the fields of the structure :
* - addr is the address in the slave device
* - addr_length is the size of the address in the slave (support for large TWI memory devices)
* - chip sets the 7 bit address of the slave device you want to communicate with
* - buffer is a pointer on the data to write to slave
* - length is the number of data to write
*
* -# Finally, call twi_master_write \code twi_master_write(&TWIM0, &packet_write); \endcode
* and optionally check its return value for TWI_SUCCESS.
* \subsection twi_basic_use_case_usage_code_reading Example code : Reading from a slave device
* Use in application C-file:
* \code
uint8_t data_received[10];
twi_package_t packet_read = {
.addr = EEPROM_MEM_ADDR, // TWI slave memory address data
.addr_length = sizeof (uint16_t), // TWI slave memory address data size
.chip = EEPROM_BUS_ADDR, // TWI slave bus address
.buffer = data_received, // transfer data destination buffer
.length = 10 // transfer data size (bytes)
};
// Perform a multi-byte read access then check the result.
if(twi_master_read(&TWIM0, &packet_read) == TWI_SUCCESS){
//Check read content
if(data_received[0]==0x55)
do_something();
}
\endcode
*
* \subsection twi_basic_use_case_usage_flow Workflow
* -# Prepare a data buffer that will receive the data from the slave device:
* \code uint8_t data_received[10]; \endcode
* -# Prepare a twi_package_t structure
* \code twi_package_t packet_read; \endcode
* Fill all the fields of the structure :
* - addr is the address in the slave device
* - addr_length is the size of the address in the slave (support for large TWI memory devices)
* - chip sets the 7 bit address of the slave device you want to communicate with
* - buffer is a pointer on the data buffer that will receive the data from the slave device
* - length is the number of data to read
*
* -# Finally, call twi_master_read \code twi_master_read(&TWIM0, &packet_read); \endcode
* and optionally check its return value for TWI_SUCCESS.
* the data read from the device are now in data_received.
*/
#endif /* TWI_MASTER_H_INCLUDED */
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