I2C.rar_at91sam7s64 twi

#include"..\inc\headfile.h" #define AT91C_EEPROM_I2C_ADDRESS (0x56<<16) int AT91F_TWI_Write(const AT91PS_TWI pTwi ,int drivers,int address, char *data2send, int size) { unsigned int status; //pTwi->TWI_MMR=(AT91C_EEPROM_I2C_ADDRESS| AT91C_TWI_IADRSZ_2_BYTE ) & ~AT91C_TWI_MREAD;//设置TWI工作模式，写 pTwi->TWI_MMR=(drivers) & ~AT91C_TWI_MREAD;//设置TWI工作模式，写 pTwi->TWI_IADR = address; //设置从机要访问的内部地址 status = pTwi->TWI_SR; //读取TWI状态寄存器 pTwi->TWI_THR = *(data2send++); //把第一个数据加载到发送保持寄存器 pTwi->TWI_CR = AT91C_TWI_START; //启动TWI的START while (size-- >1) { while (!(pTwi->TWI_SR & AT91C_TWI_TXRDY)); //等待TWI_THR为空 pTwi->TWI_THR = *(data2send++); // 把数据加载到发送保持寄存器 } pTwi->TWI_CR = AT91C_TWI_STOP; //启动TWI的STOP status = pTwi->TWI_SR; //读取TWI的状态寄存器 while (!(pTwi->TWI_SR & AT91C_TWI_TXCOMP)); // 等待发送完成 return 0; } int AT91F_TWI_Read(const AT91PS_TWI pTwi ,int drivers,int address, char *data2rec, int size) { unsigned int status; //int drivers; //pTwi->TWI_MMR=(AT91C_EEPROM_I2C_ADDRESS| AT91C_TWI_IADRSZ_2_BYTE ) | AT91C_TWI_MREAD;//设置TWI工作模式，读 pTwi->TWI_MMR=(drivers) | AT91C_TWI_MREAD;//设置TWI工作模式，读 pTwi->TWI_IADR = address; //设置从机要访问的内部地址 pTwi->TWI_CR = AT91C_TWI_START; // Start transfer status = pTwi->TWI_SR; //读取TWI状态寄存器 while (size-- >1) { while (!(pTwi->TWI_SR & AT91C_TWI_RXRDY)); //等待TWI_RHR为空 *(data2rec++) = pTwi->TWI_RHR; //读取数据 } pTwi->TWI_CR = AT91C_TWI_STOP; //启动TWI的STOP status = pTwi->TWI_SR; //读取TWI的状态寄存器 while (!(pTwi->TWI_SR & AT91C_TWI_TXCOMP)); // 等待发送完成 *data2rec = pTwi->TWI_RHR; // 读取最后一个数据 return 0; } void AT91F_SetTwiClock(const AT91PS_TWI pTwi) { int sclock; sclock = (10*MCK /AT91C_TWI_CLOCK); sclock = (MCK /AT91C_TWI_CLOCK); if (sclock % 10 >= 5) sclock = (sclock /10) - 5; else sclock = (sclock /10)- 6; sclock = (sclock + (4 - sclock %4)) >> 2; pTwi->TWI_CWGR = 0x00010000 | sclock | (sclock << 8); } void InitTwi(void) { AT91F_TWI_CfgPIO(); //配置TWI的TWD和TWCK管脚 AT91F_TWI_CfgPMC (); //使能TWI外围时钟 AT91F_TWI_Configure (AT91C_BASE_TWI); //将TWI设置成主模式 AT91F_SetTwiClock(AT91C_BASE_TWI); //计算、设置时钟发生寄存器 }