iic.rar_DM642_DM642 IIC_I2C DM642 _RTC_dm642 i2c

/***********************************************************/ /* Copyright 2003 by SEED Incorporated. */ /* All rights reserved. Property of SEED Incorporated. */ /* */ /***********************************************************/ #include "iic.h" #define I2CDELAY(iterations) { \ volatile Int j; \ for(j = 0; j < iterations; j ++); \ } #define DELAY_TIME 0x4000 /*SEEDDM642的IIC的设置结构*/ I2C_Config SEEDDM642IIC_Configt = { 0, /* master mode, i2coar;采用主模式 */ 0, /* no interrupt, i2cimr;只写，不读，采用无中断方式*/ (20-5), /* scl low time, i2cclkl; */ (20-5), /* scl high time,i2cclkh; */ 2, /* configure later, i2ccnt;*/ 0, /* configure later, i2csar;*/ 0x4620, /* master tx mode, */ /* i2c runs free, */ /* 8-bit data + NACK */ /* no repeat mode */ (75-1), /* 2MHz clock, i2cpsc */ }; I2C_Config SEEDDM642IIC_Configr = { 0, /* master mode, i2coar;采用主模式 */ 0, /* no interrupt, i2cimr;只写，不读，采用无中断方式*/ (20-5), /* scl low time, i2cclkl; */ (20-5), /* scl high time,i2cclkh; */ 1, /* configure later, i2ccnt;*/ 0, /* configure later, i2csar;*/ 0x4420, /* master tx mode, */ /* i2c runs free, */ /* 8-bit data + NACK */ /* no repeat mode */ (75-1), /* 2MHz clock, i2cpsc */ }; /* * ======== _IIC_write ======== * This function performs write operation via I2C bus. */ /* Spin in a delay loop for delay iterations */ void EVMDM642_wait(Uint32 delay) { volatile Uint32 i, n; n = 0; for (i = 0; i < delay; i++) { n = n + 1; } } /* Spin in a delay loop for delay microseconds */ void EVMDM642_waitusec(Uint32 delay) { EVMDM642_wait(delay * 21); } void _IIC_write(I2C_Handle hI2C, Uint8 devAddress, Uint32 subAddress, Uint8 data ) { I2C_Config prevI2CCfg; /* Wait until bus is free */ while (I2C_bb(hI2C)); /* Save old settings */ I2C_getConfig(hI2C, &prevI2CCfg); /* Restore settings for AIC23 */ SEEDDM642IIC_Configt.i2csar = devAddress; I2C_config(hI2C, &SEEDDM642IIC_Configt); /* Submit the MSB for transmit */ I2C_RSETH(hI2C, I2CDXR, (subAddress) & 0xff); /* Generate start condition, starts transmission */ I2C_start(hI2C); /* Wait until MSB transmit is done */ while(!I2C_xrdy(hI2C)); /* Submit the LSB for transmit */ I2C_RSETH(hI2C, I2CDXR,data); // EVMDM642_waitusec(350); /* Generate stop condition */ I2C_sendStop(hI2C); /* Wait until bus is free */ while (I2C_bb(hI2C)); EVMDM642_waitusec(350); /* Reconfigure I2C with old settings */ I2C_config(hI2C, &prevI2CCfg); } /* * ======== _IIC_read ======== * This function performs read from operation via I2C bus. */ void _IIC_read(I2C_Handle hI2C, Uint8 devAddress, Uint32 subAddress, Uint8 *data ) { I2C_Config prevI2CCfg; /* Wait until bus is free */ while (I2C_bb(hI2C)); /* Save old settings */ I2C_getConfig(hI2C, &prevI2CCfg); /* Restore settings for AIC23 */ SEEDDM642IIC_Configt.i2csar = devAddress; I2C_config(hI2C, &SEEDDM642IIC_Configt); /* Submit the MSB for transmit */ I2C_RSETH(hI2C, I2CDXR, (subAddress) & 0xff); /* Generate start condition, starts transmission */ I2C_start(hI2C); /* Wait until MSB transmit is done */ while(!I2C_xrdy(hI2C)); /* Generate stop condition */ I2C_sendStop(hI2C); EVMDM642_waitusec(20); /* Reconfigure I2C with old settings */ I2C_config(hI2C, &prevI2CCfg); I2C_getConfig(hI2C, &prevI2CCfg); /*从发送到接收需一段时间转换*/ EVMDM642_waitusec(0x200); /* Restore settings for AIC23 */ SEEDDM642IIC_Configr.i2csar = devAddress; I2C_config(hI2C, &SEEDDM642IIC_Configr); /* Generate start condition, starts transmission */ I2C_start(hI2C); while(I2C_FGETH(hI2C,I2CSTR,ARDY)); /* Wait until MSB transmit is done */ while(!I2C_rrdy(hI2C)); /* Submit the MSB for transmit */ *data = I2C_RGETH(hI2C, I2CDRR); /* Generate stop condition */ I2C_sendStop(hI2C); /* Wait until bus is free */ while (I2C_bb(hI2C)); /* Short delay for AIC23 to accept command */ EVMDM642_waitusec(20); /* Reconfigure I2C with old settings */ I2C_config(hI2C, &prevI2CCfg); }