i2c.c

测试TI DSP的C6000系列中的I2C能否正常工作

#include "iic.h"

//#define DELAY_TIME 1000
#define DELAY_TIME 200
#define I2CDELAY(iterations)  {      \
    volatile Int j;                  \
    for(j = 0; j < iterations; j ++); \
}    

static I2C_Config EVM642VIDEOIIC_repeat_wr_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;*/
    0x46a0, /* i2cmdr,     */
    		/* master tx mode,     */
            /* i2c runs free,      */
            /* 8-bit data + NACK   */
            /* repeat mode,  i2ccnt is not used  */
    (75-1), /* 4MHz clock, i2cpsc  */
};

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  */
};

static I2C_Config EVM642VIDEOIIC_repeat_rd_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;*/
    0x4420, /* i2cmdr,     */
    		/* master rx mode,     */
            /* i2c runs free,      */
            /* 8-bit data + NACK   */
            /* repeat mode,  i2ccnt is not used  */
    (75-1), /* 4MHz clock, i2cpsc  */
};

Uint8 IIC_read8(I2C_Handle hI2C,
              Uint8   devAddress,
              Uint32  subAddress
              )
{             

    Uint8  read_data;
    int i_read_data;
    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);
	I2C_config(hI2C, &EVM642VIDEOIIC_repeat_wr_Config);

	/* configure the I2C slave address register */
	I2C_RSETH(hI2C, I2CSAR, devAddress); 

	/* Generate start condition */
	I2C_start(hI2C);
    
	I2CDELAY(DELAY_TIME);

	read_data=(subAddress & 0xff);/* subaddress  */
	while(!I2C_xrdy(hI2C));
//	I2C_writeByte(hI2C, read_data);  CAUSE ERROR IN BIG-ENDIAN
	*((Uint32 *)hI2C->i2cdxrAddr) = read_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); 
	I2CDELAY(DELAY_TIME);  /*It has to be added by double delay.Otherwise it refuses to work.*/

	/* set I2C mode register */
	I2C_config(hI2C, &EVM642VIDEOIIC_repeat_rd_Config);
	/* configure the I2C slave address register */
	I2C_RSETH(hI2C, I2CSAR, devAddress); 

	I2CDELAY(DELAY_TIME); 
	/* Generate start condition */


	I2C_start(hI2C);
    

	/* read the data */ 
	while(!I2C_rrdy(hI2C));
//	read_data = I2C_readByte(hI2C);
	read_data = (Uint8) *((Uint32 *)hI2C->i2cdrrAddr);   

	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 */
       
	I2C_config(hI2C, &prevIICConfig);

    I2CDELAY(DELAY_TIME);  
    
    return  read_data;    
           
}  


Uint16 IIC_read16(I2C_Handle hI2C,
              Uint8   devAddress,
              Uint32  subAddress
              )
{             

    Uint16  read_data16;
    Uint8  read1_data8;
    Uint8  read2_data8;
    Uint8 read_add;
    int i_read_data;
    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);
	I2C_config(hI2C, &EVM642VIDEOIIC_repeat_wr_Config);

	/* configure the I2C slave address register */
	I2C_RSETH(hI2C, I2CSAR, devAddress); 

	/* Generate start condition */
	I2C_start(hI2C);
    
	I2CDELAY(DELAY_TIME);

	read_add=(subAddress & 0xff);/* subaddress  */
	while(!I2C_xrdy(hI2C));
//	I2C_writeByte(hI2C, read_data);  CAUSE ERROR IN BIG-ENDIAN
	*((Uint32 *)hI2C->i2cdxrAddr) = read_add;        

	I2CDELAY(DELAY_TIME);

	/* Generate stop condition */
	I2C_sendStop(hI2C); 
    
	I2CDELAY(DELAY_TIME);        
	/* Wait until bus is free */
	while (I2C_bb(hI2C));

	I2CDELAY(DELAY_TIME); 
	I2CDELAY(DELAY_TIME);  /*It has to be added by double delay.Otherwise it refuses to work.*/

	/* set I2C mode register */
	I2C_config(hI2C, &EVM642VIDEOIIC_repeat_rd_Config);
	/* configure the I2C slave address register */
	I2C_RSETH(hI2C, I2CSAR, devAddress); 

	I2CDELAY(DELAY_TIME); 
	/* Generate start condition */


	I2C_start(hI2C);
    

	/* read the data */ 
	while(!I2C_rrdy(hI2C));
	read1_data8 = I2C_readByte(hI2C);
	DM642_wait(10);
    read2_data8 = I2C_readByte(hI2C);
	
	//read1_data8 = (Uint8) *((Uint32 *)hI2C->i2cdrrAddr);  
	//read2_data8 = (Uint8) *((Uint32 *)hI2C->i2cdrrAddr +1);   

	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 */
       
	I2C_config(hI2C, &prevIICConfig);

    I2CDELAY(DELAY_TIME);  
    read_data16 = (read1_data8 | (read1_data8<<8));
    
    return  read_data16;    
           
}  

   
/**********************************/ 

/*
 * ======== _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 ++); CAUSE ERROR IN BIG-ENDIAN
		*((Uint32 *)hI2C->i2cdxrAddr) = *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); 
    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);  
    I2CDELAY(DELAY_TIME);       
}