CODEWITHSUNDEEP
cpici2c
darthvader211
darthvader211

Reputation: 11

I2C Communication with EEPROM

I basically have this problem that has been bugging me for a while. I have a PIC32MX128L128H processor and a Basic I/O Shield. The pins and everything is done correctly, except for my communication with the EEPROM with I2C. I will copy my code below, but before, I there are the controls:

I2C1CON: bit 0 SEN: Start Condition Enable bit bit 2 PEN: Stop Condition Enable bit bit 3 RCEN: Receive Enable bit bit 4 ACKEN: Acknowledge Sequence Enable bit bit 5 ACKDT: Acknowledge Data bit

I2C1STAT: bit 15 ACKSTAT: Acknowledge Status bit (1 = not received, 0 = received) bit 14 TRSTAT: Transmit Status bit bit 6 I2COV: I2C Receive Overflow Status bit

Thank you!

void EEPROM_wait(){
  while(I2C1STAT & (1 << 15)){

    I2C1CON |= 0x1;
    while(I2C1CON & 0x1);

    I2C1TRN = 0xa0;
    while(I2C1STAT & (1 << 14));

  }
}

void i2c_wait(){
  while(I2C1CON & 0x1f || I2C1STAT & (1 << 14));
}




void writeByte(uint8_t lowByte, uint8_t highByte, uint8_t data){


  //Start Procedure
  do{
  I2C1CON |= 0x1;
  i2c_wait();
  I2C1TRN = 0xa0;
  i2c_wait();
  } while(I2C1STAT & (1 << 15));
  //Send the adress of the EEPROM and also R/W bit

  //Send highByte
  I2C1TRN = highByte;
  i2c_wait();

  //Send lowByte
  I2C1TRN = lowByte;
  i2c_wait();

  //Send actual data
  I2C1TRN = data;
  i2c_wait();

  //Stop the procedure
  I2C1CON |= 0x4;
  i2c_wait();

  EEPROM_wait();



}


uint8_t readByte(uint8_t lowByte, uint8_t highByte)
{



  //Initialize Procedure
  do{
  I2C1CON |= 0x1;
  i2c_wait();
  I2C1TRN = 0xa0;
  i2c_wait();
  }while(I2C1STAT & (1 << 15));

  //Send the address of the EEPROM
  //I2C1TRN = 0xa0;
  //i2c_wait();

  //Send highByte
  I2C1TRN = highByte;
  i2c_wait();

  //Send lowByte

  I2C1TRN = lowByte;
  i2c_wait();

  //Initialize Procedure Read
  do{
  I2C1CON |= 0x1;
  i2c_wait();
  I2C1TRN = 0xa1;
  i2c_wait();
  } while (I2C1STAT & (1 << 15));

  //Send the address of the EEPROM with Read bit
  //I2C1TRN = 0xa1;
  //i2c_wait();

  //Enable Receive Procedure
  I2C1CON |= 1 << 3;
  i2c_wait();
  I2C1STATCLR = 1 << 6;

  //Read from the EEPROM
  uint8_t rtn = I2C1RCV;

  //Acknowledge
  I2C1CON &= ~(1 << 5);
  I2C1CON |= 1 << 4;

  //Stop Procedure
  I2C1CON |= 1 << 2;
  i2c_wait();

  return rtn;

}

Upvotes: 0

Views: 251

Answers (1)

darthvader211
darthvader211

Reputation: 11

I realised what the problem was. The chipkit bus clock rate was not set the same as the i2c bus clock which led in midwriting or misreading.

Upvotes: 0

Related Questions