?? twi.c
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//*--------------------------------------------------------------------------------------
//* ATMEL Microcontroller Software Support - ROUSSET -
//*--------------------------------------------------------------------------------------
//* The software is delivered "AS IS" without warranty or condition of any
//* kind, either express, implied or statutory. This includes without
//* limitation any warranty or condition with respect to merchantability or
//* fitness for any particular purpose, or against the infringements of
//* intellectual property rights of others.
//*--------------------------------------------------------------------------------------
//* File Name : twi.c
//* Object : Basic TWI EEPROM driver
//* Translator :
//* 1.0 25/11/02 NL : Creation
//*--------------------------------------------------------------------------------------
#include <AT91RM9200.H> // AT91RM9200 definitions
#include <lib_AT91RM9200.h> // Library function definitions
#include "main.h"
#include "twi.h"
//*=========================================================
//* WRITE
//*=========================================================
//*----------------------------------------------------------------------------
//* \fn AT91F_TWI_Write
//* \brief Send n bytes to a slave device
//*----------------------------------------------------------------------------
int AT91F_TWI_Write(const AT91PS_TWI pTwi ,int address, char *data2send, int size)
{
// Set the TWI Master Mode Register
pTwi->TWI_MMR = ( AT91C_EEPROM_I2C_ADDRESS | AT91C_TWI_IADRSZ_2_BYTE ) & ~AT91C_TWI_MREAD;
// Set TWI Internal Address Register
pTwi->TWI_IADR = address;
pTwi->TWI_THR = *(data2send++);
pTwi->TWI_CR = AT91C_TWI_START;
while (size-- >1){
// Wait THR Holding register to be empty
while (!(pTwi->TWI_SR & AT91C_TWI_TXRDY));
// Send first byte
pTwi->TWI_THR = *(data2send++);
}
pTwi->TWI_CR = AT91C_TWI_STOP;
// Wait transfer is finished
while (!(pTwi->TWI_SR & AT91C_TWI_TXCOMP));
return AT91C_EEPROM_WRITE_OK;
}
//*=========================================================
//* READ
//*=========================================================
//*----------------------------------------------------------------------------
//* \fn AT91F_TWI_Read
//* \brief Read n bytes from a slave device
//*----------------------------------------------------------------------------
int AT91F_TWI_Read(const AT91PS_TWI pTwi , int address, char *data, int size)
{
// Set the TWI Master Mode Register
pTwi->TWI_MMR = AT91C_EEPROM_I2C_ADDRESS | AT91C_TWI_IADRSZ_2_BYTE | AT91C_TWI_MREAD;
// Set TWI Internal Address Register
pTwi->TWI_IADR = address;
// Start transfer
pTwi->TWI_CR = AT91C_TWI_START;
while (size-- >1){
// Wait RHR Holding register is full
while (!(pTwi->TWI_SR & AT91C_TWI_RXRDY));
// Read byte
*(data++) = pTwi->TWI_RHR;
}
pTwi->TWI_CR = AT91C_TWI_STOP;
// Wait transfer is finished
while (!(pTwi->TWI_SR & AT91C_TWI_TXCOMP));
// Read last byte
*data = pTwi->TWI_RHR;
return AT91C_EEPROM_READ_OK;
}
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