TM4C123GH6PM: I2C communication with HMC5883L (3-Axis Digital Compass IC)

Hello Everyone,

I am trying to read data from HMC5883L. I have tried to establish a communication network according to HMC5883L datasheet but I can not read the data. I would appreciate it if you could go through my code and advise me how I could fix the problem. Thanks in advance for your time.

#include "tm4c123gh6pm.h"

//Global Variables
int i=0;
unsigned long DATA;

//


#define I2C_MCS_ACK             0x00000008  // Data Acknowledge Enable
#define I2C_MCS_DATACK          0x00000008  // Acknowledge Data
#define I2C_MCS_ADRACK          0x00000004  // Acknowledge Address
#define I2C_MCS_STOP            0x00000004  // Generate STOP
#define I2C_MCS_START           0x00000002  // Generate START
#define I2C_MCS_ERROR           0x00000002  // Error
#define I2C_MCS_RUN             0x00000001  // I2C Master Enable
#define I2C_MCS_BUSY            0x00000001  // I2C Busy
#define I2C_MCR_MFE             0x00000010  // I2C Master Function Enable

#define MAXRETRIES              5           // number of receive attempts before giving up

void I2C0_Init(void){
  SYSCTL_RCGCI2C_R |= 0x0001;            // activate I2C0
  SYSCTL_RCGCGPIO_R |= 0x0002;           // activate port B
  while((SYSCTL_PRGPIO_R&0x0002) == 0){};// ready?

  GPIO_PORTB_AFSEL_R |= 0x0C;           // 3) enable alt funct on PB2,3
  GPIO_PORTB_ODR_R |= 0x08;             // 4) enable open drain on PB3 only
  GPIO_PORTB_DEN_R |= 0x0C;             // 5) enable digital I/O on PB2,3
                                        // 6) configure PB2,3 as I2C
  GPIO_PORTB_PCTL_R = (GPIO_PORTB_PCTL_R&0xFFFF00FF)+0x00003300;
  GPIO_PORTB_AMSEL_R &= ~0x0C;          // 7) disable analog functionality on PB2,3
  I2C0_MCR_R = I2C_MCR_MFE;      // 9) master function enable
  I2C0_MTPR_R = 0x07;              // 8) configure for 100 kbps clock
  // 16MHZ*(TPR+1)*20ns => TPR=7
}

void Slave_Address (unsigned long slaveAddress){
	
	I2C1_MSA_R= ((slaveAddress) << 1);
	
}

void EndTransmission (void){
  while(I2C0_MCS_R&I2C_MCS_BUSY){};// wait for I2C ready
  //I2C0_MSA_R &= ~0x01;             // MSA[0] is 0 for send
 // I2C0_MDR_R = data1&0xFF;         // prepare first byte
  I2C0_MCS_R = (0
                        //  & ~I2C_MCS_ACK     // no data ack (no data on send)
														| I2C_MCS_STOP     // generate stop
                        //  | I2C_MCS_START    // no start/restart
                            | I2C_MCS_RUN);    // master enable
  while(I2C0_MCS_R&I2C_MCS_BUSY){};// wait for transmission done
                                        
}

unsigned long I2C_Send_NO_START ( unsigned long data1){
  while(I2C0_MCS_R&I2C_MCS_BUSY){};// wait for I2C ready
  I2C0_MSA_R &= ~0x01;             // MSA[0] is 0 for send
  I2C0_MDR_R = data1&0xFF;         // prepare first byte
  I2C0_MCS_R = (0
                      // & ~I2C_MCS_ACK     // no data ack (no data on send)
                      // | I2C_MCS_STOP     // no stop
                      // | I2C_MCS_START    // no start/restart
                         | I2C_MCS_RUN);    // master enable
  while(I2C0_MCS_R&I2C_MCS_BUSY){};// wait for transmission done
                                          // return error bits
  return (I2C0_MCS_R&(I2C_MCS_DATACK|I2C_MCS_ADRACK|I2C_MCS_ERROR));
}


unsigned long I2C_Send_NO_STOP ( unsigned long data1){
  while(I2C0_MCS_R&I2C_MCS_BUSY){};// wait for I2C ready
  I2C0_MSA_R &= ~0x01;             // MSA[0] is 0 for send
  I2C0_MDR_R = data1&0xFF;         // prepare first byte
  I2C0_MCS_R = (0
                    //   & ~I2C_MCS_ACK     // no data ack (no data on send)
                    //   | I2C_MCS_STOP     // generate stop
                         | I2C_MCS_START    // generate start/restart
                         | I2C_MCS_RUN);    // master enable
  while(I2C0_MCS_R&I2C_MCS_BUSY){};// wait for transmission done
                                          // return error bits
  return (I2C0_MCS_R&(I2C_MCS_DATACK|I2C_MCS_ADRACK|I2C_MCS_ERROR));
}

unsigned long I2C_Recv(unsigned long slave){
  int retryCounter = 1;
  do{
    while(I2C0_MCS_R&I2C_MCS_BUSY){};// wait for I2C ready
    I2C0_MSA_R = (slave<<1)&0xFE;    // MSA[7:1] is slave address
    I2C0_MSA_R |= 0x01;              // MSA[0] is 1 for receive
    I2C0_MCS_R = (0
                        // & ~I2C_MCS_ACK     // negative data ack (last byte)
                         | I2C_MCS_STOP     // generate stop
                         | I2C_MCS_START    // generate start/restart
                         | I2C_MCS_RUN);    // master enable
    while(I2C0_MCS_R&I2C_MCS_BUSY){};// wait for transmission done
    retryCounter = retryCounter + 1;        // increment retry counter
  }                                         // repeat if error
  while(((I2C0_MCS_R&(I2C_MCS_ADRACK|I2C_MCS_ERROR)) != 0) && (retryCounter <= MAXRETRIES));
  return (I2C0_MDR_R&0xFF);          // usually returns 0xFF on error
}


void SystemInit (void){}
	
int main (void){
I2C0_Init();
Slave_Address (0x1E);        // Slave Address is 0x1E according to HMC5883L datasheet

//initialization process for “continuous-measurement mode (HMC5883L) Page 18
   
 //(8-average, 15 Hz default, normal measurement)
	I2C_Send_NO_STOP (0x3C);
	I2C_Send_NO_START (0x00);
	I2C_Send_NO_START (0x70);

 //(Gain=5, or any other desired gain)
	I2C_Send_NO_STOP (0x3C);
	I2C_Send_NO_START (0x01);
	I2C_Send_NO_START (0xA0);

 //(Continuous-measurement mode)
  I2C_Send_NO_STOP  (0x3C);
	I2C_Send_NO_START (0x02);
	I2C_Send_NO_START (0x00);

//Delay
	for ( i =0 ; i< 100000; i++){};
	for ( i =0 ; i< 100000; i++){};

// End Transmission
EndTransmission ();


while (1){

Slave_Address (0x1E);
I2C_Send_NO_STOP (0x3D);		// I2C Address to Read Data according to HMC5883L datasheet page 2
I2C_Send_NO_START (0x03);		// Address location 03 which is X-MSB  
DATA = I2C_Recv(0x1E);			//Reading X-MSB  

}

}