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/**
* \file
*
* \brief TWIHS Master Mode management
*
* Copyright (c) 2014-2015 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 TWIHS_MASTER_H_INCLUDED
#define TWIHS_MASTER_H_INCLUDED
#include <parts.h>
#include <compiler.h>
#if (SAMG || SAMV70 || SAMV71 || SAME70 || SAMS70)
# include "sam_twihs/twihs_master.h"
#else
# error Unsupported chip type
#endif
/**
*
* \defgroup twihs_group Two Wire-interface High Speed(TWIHS)
*
* This is the common API for TWIHS. Additional features are available
* in the documentation of the specific modules.
*
* See \ref twihs_quickstart.
*
* \section twihs_group_platform Platform Dependencies
*
* The TWIHS 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 TWIHS Module initialization
* \code status_code_t twihs_master_setup(*twihs_module_pointer, twihs_master_options_t *opt) \endcode
* - Enables TWIHS Module
* \code void twihs_master_enable(*twihs_module_pointer) \endcode
* - Disables TWIHS Module
* \code void twihs_master_disable(*twihs_module_pointer) \endcode
* - Read data from a slave device
* \code status_code_t twihs_master_read(*twihs_module_pointer, twihs_package_t *package) \endcode
* - Write data from to a slave device
* \code status_code_t twihs_master_write(*twihs_module_pointer, twihs_package_t *package) \endcode
*
* @{
*/
/**
* \typedef twihs_master_t
* This type can be used independently to refer to TWIHS master module for the
* architecture used. It refers to the correct type definition for the
* architecture.
*/
//! @}
/**
* \page twihs_quickstart Quickstart guide for Common service TWIHS
*
* This is the quickstart guide for the \ref twihs_group "Common service TWIHS",
* 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 twihs_basic_use_case Basic use case
* In the most basic use case, the TWIHS module is configured for
* - Master operation
* - addressing one slave device of the bus at address 0x50
* - TWIHS clock of 400kHz
* - polled read/write handling
*
* \section twihs_basic_use_case_setup Setup steps
* \subsection twihs_basic_use_case_setup_code Example code
* Add to your application C-file, for example in SAM series chip:
* \code
void twihs_init(void)
{
twihs_master_options_t opt = {
.speed = 400000,
.chip = 0x50
};
twihs_master_setup(&TWIM0, &opt);
}
\endcode
*
* \subsection twihs_basic_use_case_setup_flow Workflow
* -# Ensure that board_init() has configured selected I/Os for TWIHS 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 TWIHS module in your TWIHS initialization
* function, for example in SAM series chip:
* - \code
twihs_master_options_t opt = {
.speed = 400000,
.chip = 0x50
}; \endcode
* - field \ref speed sets the baudrate of the TWIHS bus
* - field \ref chip sets the address of the slave device you want to communicate with
* -# Call twihs_master_setup and optionally check its return code
* - \note The config structs can be reused for other TWIHS modules
* after this step. Simply reconfigure and write to others modules.
*
* \section twihs_basic_use_case_usage Usage steps
* \subsection twihs_basic_use_case_usage_code_writing Example code : Writing to a slave device
* Use in application C-file, for example in SAM series chip:
* \code
const uint8_t test_pattern[] = {0x55,0xA5,0x5A,0x77,0x99};
twihs_package_t packet_write = {
.addr = EEPROM_MEM_ADDR, // TWIHS slave memory address data
.addr_length = sizeof (uint16_t), // TWIHS slave memory address data size
.chip = EEPROM_BUS_ADDR, // TWIHS slave bus address
.buffer = (void *)test_pattern, // transfer data source buffer
.length = sizeof(test_pattern) // transfer data size (bytes)
};
while (twihs_master_write(&TWIM0, &packet_write) != TWI_SUCCESS);
\endcode
*
* \subsection twihs_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 twihs_package_t structure
* \code twihs_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 twihs_master_write \code twihs_master_write(&TWIM0, &packet_write); \endcode
* and optionally check its return value for TWI_SUCCESS.
* \subsection twihs_basic_use_case_usage_code_reading Example code : Reading from a slave device
* Use in application C-file, for example in SAM series chip:
* \code
uint8_t data_received[10];
twihs_package_t packet_read = {
.addr = EEPROM_MEM_ADDR, // TWIHS slave memory address data
.addr_length = sizeof (uint16_t), // TWIHS slave memory address data size
.chip = EEPROM_BUS_ADDR, // TWIHS 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(twihs_master_read(&TWIM0, &packet_read) == TWI_SUCCESS){
//Check read content
if(data_received[0]==0x55)
do_something();
}
\endcode
*
* \subsection twihs_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 twihs_package_t structure
* \code twihs_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 twihs_master_read \code twihs_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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