Subversion Repositories oms8051mini

/*

 * I2C Master Burst Write and Read Test

 *

 * I2C Master Write to Slave Chip with Id: 0x20

 *

 * Burst 4 Byte Write  to address starting from 0x66 with 0x12, 0x34, 0x56 and 0x78

 * Read Back in Burst mode and verify the expected data

 */

/*---------------------------------------------------------------------------*/

#include <8051.h>

char cErrCnt;

/*---------------------------------------------------------------------------*/

__xdata __at (0xA000) unsigned char i2c_prescale_low;

__xdata __at (0xA001) unsigned char i2c_prescale_high;

__xdata __at (0xA002) unsigned char i2c_control;

volatile __xdata __at (0xA003) unsigned char i2c_data;

volatile __xdata __at (0xA004) unsigned char i2c_cmd;

void main() {

   int ErrCnt = 0;

  //Wrire Prescale registers

   i2c_prescale_low  = 0xC7;

   i2c_prescale_high = 0x00;

  // Core Enable

  i2c_control = 0x80;

  // Writing Data

  i2c_data = 0x20; // Slave Addr + WR

  i2c_cmd  = 0x90;

  while(i2c_cmd & 0x2);

  // Memory Address 

  i2c_data = 0x66;

  i2c_cmd  = 0x10;

  while(i2c_cmd & 0x2);

 /* Byte1: 12 */

  i2c_data = 0x12;

  i2c_cmd  = 0x10;

  while(i2c_cmd & 0x2);

 /* Byte2: 34 */

  i2c_data = 0x34;

  i2c_cmd  = 0x10;

  while(i2c_cmd & 0x2);

 /* Byte3: 56 */

  i2c_data = 0x56;

  i2c_cmd  = 0x10;

  while(i2c_cmd & 0x2);

 /* Byte4: 78 */

  i2c_data = 0x78;

  i2c_cmd  = 0x50; // Stop + Write

  while(i2c_cmd & 0x2);

  //Reading Data

  // Slave Address + Write 

  i2c_data = 0x20;

  i2c_cmd  = 0x90;

  while(i2c_cmd & 0x2);

  // Memorry Address

  i2c_data = 0x66;

  i2c_cmd  = 0x50; // Stop 

  while(i2c_cmd & 0x2);

  //Burst Read

  i2c_data = 0x21;

  i2c_cmd  = 0x90;

  while(i2c_cmd & 0x2);

  /* BYTE-1 : 0x12  */

  i2c_cmd  = 0x20;

  while(i2c_cmd & 0x2);

  if(i2c_data != 0x12) ErrCnt++;

  /* BYTE-2 : 0x34  */

  i2c_cmd  = 0x20;

  while(i2c_cmd & 0x2);

  if(i2c_data != 0x34) ErrCnt++;

  /* BYTE-3 : 0x56  */

  i2c_cmd  = 0x20;

  while(i2c_cmd & 0x2);

  if(i2c_data != 0x56) ErrCnt++;

  /* BYTE-4 : 0x78  */

  i2c_cmd  = 0x68; // STOP + RD + NACK 

  while(i2c_cmd & 0x2);

  if(i2c_data != 0x78) ErrCnt++;

    if(ErrCnt !=0) {

        P2 = 0x55; // Test Fail

        P3 = ErrCnt;

    } else {

       P2 = 0xAA; // Test PASS

       P3 = 0xAA; // Test PASS

    }

    while(1);

}