www.pudn.com > H265+_C64X_2008.8.rar > _iic.c

/* 
 *  Copyright 2003 by Texas Instruments Incorporated. 
 *  All rights reserved. Property of Texas Instruments Incorporated. 
 *  Restricted rights to use, duplicate or disclose this code are 
 *  granted through contract. 
 *   
 */ 
/* "@(#) DDK 1.10.00.23 07-02-03 (ddk-b12)" */ 
#include "_iic.h"       
 
#define I2CDELAY(iterations)  {      \ 
    volatile Int j;                  \ 
    for(j = 0; j < iterations; j ++); \ 
}    
#define DELAY_TIME 1000 
 
static const I2C_Config EVM642VIDEOIIC_Config = { 
    0,  /* master mode,  i2coar;   */ 
    0,  /* no interrupt, i2cimr;   */ 
    (20-5), /* scl low time, i2cclkl;  */ 
    (20-5), /* scl high time,i2cclkh;  */ 
    1,  /* configure later, i2ccnt;*/ 
    0,  /* configure later, i2csar;*/ 
    0x4620, /* master tx mode,     */ 
            /* i2c runs free,      */ 
            /* 8-bit data + NACK   */ 
            /* no repeat mode      */ 
    (75-1), /* 4MHz clock, i2cpsc  */ 
}; 
 
/* 
 * ======== _IIC_write ======== 
 * This function performs write operation via I2C bus. 
 */ 
 
void _IIC_write(I2C_Handle hI2C, 
              Uint8 devAddress, 
              Uint32  subAddress, 
              Uint8 *data, 
              Uint16  numBytes 
              ) 
{              
    Int i; 
    I2C_Config prevIICConfig;  
     
    /* make sure handle is valid */ 
    if(hI2C == INV) { 
        return; 
    } 
     
    /* Wait until bus is free */ 
    while (I2C_bb(hI2C)); 
 
    /* save old settings */ 
    I2C_getConfig(hI2C, &prevIICConfig); 
 
    /* set I2C mode register */ 
    I2C_RSETH(hI2C, I2CMDR, EVM642VIDEOIIC_Config.i2cmdr); 
     
    /* set I2C imr register  */ 
    I2C_RSETH(hI2C, I2CIMR, EVM642VIDEOIIC_Config.i2cimr); 
     
    /* configure the I2C slave address register */ 
    I2C_RSETH(hI2C, I2CSAR, devAddress); 
     
    /* set I2C count register */ 
    I2C_RSETH(hI2C, I2CCNT, numBytes + 1); 
     
    /* write the sub address */ 
    I2C_RSETH(hI2C, I2CDXR, subAddress); 
     
    /* Generate start condition */ 
    I2C_start(hI2C); 
     
    I2CDELAY(DELAY_TIME); 
 
    /* write the data */  
    for(i = 0; i < numBytes; i ++) { 
        while(!I2C_xrdy(hI2C)); 
        I2C_writeByte(hI2C, *data ++); 
        I2CDELAY(DELAY_TIME); 
    } 
 
    /* Generate stop condition */ 
    I2C_sendStop(hI2C);  
     
    I2CDELAY(DELAY_TIME);         
    /* Wait until bus is free */ 
    while (I2C_bb(hI2C)); 
 
    I2CDELAY(DELAY_TIME);         
    /* now restore the previous I2C settings */ 
     
    /* set I2C mode register */ 
    I2C_RSETH(hI2C, I2CMDR, prevIICConfig.i2cmdr); 
     
    /* set I2C imr register  */ 
    I2C_RSETH(hI2C, I2CIMR, prevIICConfig.i2cimr); 
     
    /* configure the I2C slave address register */ 
    I2C_RSETH(hI2C, I2CSAR, prevIICConfig.i2csar); 
     
    /* set I2C count register */ 
    I2C_RSETH(hI2C, I2CCNT, prevIICConfig.i2ccnt); 
 
    I2CDELAY(DELAY_TIME);         
}