File content as of revision 6:5fe568883921:

/**************************************************************************************************************************************************************
//  This is a modified version of mbed /users/bclaus/code/LSM303DLHC/ for LSM303DLHC
//
//  Changes made by Ryan Spillman:
//  Added initialization function to configure ODR, filters, and other settings
//  Added seperate functions for reading the magnetometer and acclerometer seperately (they do not operate at the same ODR)
**************************************************************************************************************************************************************/
#include "mbed.h"
#include "LSM303DLHC.h"


const int addr_acc = 0x32;
const int addr_mag = 0x3c;

enum REG_ADDRS {
    /* --- Mag --- */
    CRA_REG_M   = 0x00,
    CRB_REG_M   = 0x01,
    MR_REG_M    = 0x02,
    OUT_X_M     = 0x03,
    OUT_Y_M     = 0x05,
    OUT_Z_M     = 0x07,
    /* --- Acc --- */
    CTRL_REG1_A = 0x20,
    CTRL_REG4_A = 0x23,
    OUT_X_A     = 0x28,
    OUT_Y_A     = 0x2A,
    OUT_Z_A     = 0x2C,
};

bool LSM303DLHC::write_reg(int addr_i2c,int addr_reg, char v)
{
    char data[2] = {addr_reg, v}; 
    return LSM303DLHC::_LSM303.write(addr_i2c, data, 2) == 0;
}

bool LSM303DLHC::read_reg(int addr_i2c,int addr_reg, char *v)
{
    char data = addr_reg; 
    bool result = false;
    
    __disable_irq();
    if ((_LSM303.write(addr_i2c, &data, 1) == 0) && (_LSM303.read(addr_i2c, &data, 1) == 0)){
        *v = data;
        result = true;
    }
    __enable_irq();
    return result;
}


LSM303DLHC::LSM303DLHC(PinName sda, PinName scl):
    _LSM303(sda, scl)
{
    char reg_v;
    _LSM303.frequency(100000);
        
    reg_v = 0;
    
    reg_v |= 0x27;          /* X/Y/Z axis enable. */
    write_reg(addr_acc,CTRL_REG1_A,reg_v);

    reg_v = 0;
   // reg_v |= 0x01 << 6;     /* 1: data MSB @ lower address */
    reg_v = 0x01 << 4;     /* +/- 4g */
    write_reg(addr_acc,CTRL_REG4_A,reg_v);

    /* -- mag --- */
    reg_v = 0;
    //leave line below commented for 0.75Hz data output rate (less noise)
    //reg_v |= 0x04 << 2;     /* Minimum data output rate = 15Hz */
    write_reg(addr_mag,CRA_REG_M,reg_v);
    
    reg_v = 0;
    reg_v |= 0x01 << 5;     /* +-1.3Gauss */
    //reg_v |= 0x07 << 5;     /* +-8.1Gauss */
    write_reg(addr_mag,CRB_REG_M,reg_v);

    reg_v = 0;              /* Continuous-conversion mode */
    write_reg(addr_mag,MR_REG_M,reg_v);
}


bool LSM303DLHC::read(float *ax, float *ay, float *az, float *mx, float *my, float *mz) {
    char acc[6], mag[6];
 
    if (recv(addr_acc, OUT_X_A, acc, 6) && recv(addr_mag, OUT_X_M, mag, 6)) {
        *ax = float(short(acc[1] << 8 | acc[0]))/8192;  //32768/4=8192
        //*ax = float(short(acc[1] << 8 | acc[0]));
        *ay =  float(short(acc[3] << 8 | acc[2]))/8192;
        //*ay =  float(short(acc[3] << 8 | acc[2]));
        *az =  float(short(acc[5] << 8 | acc[4]))/8192;
        //*az =  float(short(acc[5] << 8 | acc[4]));
        //full scale magnetic readings are from -2048 to 2047
        //gain is x,y =1100; z = 980 LSB/gauss
        *mx = float(short(mag[0] << 8 | mag[1]))/1100;
        //*mx = float(short(mag[0] << 8 | mag[1]))/450;
        //*mx = float(short(mag[0] << 8 | mag[1]));
        *mz = float(short(mag[2] << 8 | mag[3]))/980;
        //*mz = float(short(mag[2] << 8 | mag[3]))/400;
        //*mz = float(short(mag[2] << 8 | mag[3]));
        *my = float(short(mag[4] << 8 | mag[5]))/1100;
        //*my = float(short(mag[4] << 8 | mag[5]))/450;
        //*my = float(short(mag[4] << 8 | mag[5]));
 
        return true;
    }
 
    return false;
}

bool LSM303DLHC::ReadAccOnly(float *ax, float *ay, float *az) 
{
    char acc[6];
 
    if (recv(addr_acc, OUT_X_A, acc, 6)) 
    {
        *ax = float(short(acc[1] << 8 | acc[0]))/8192;  //32768/4=8192
        //*ax = float(short(acc[1] << 8 | acc[0]));
        *ay =  float(short(acc[3] << 8 | acc[2]))/8192;
        //*ay =  float(short(acc[3] << 8 | acc[2]));
        *az =  float(short(acc[5] << 8 | acc[4]))/8192;
        //*az =  float(short(acc[5] << 8 | acc[4]));
 
        return true;
    }
 
    return false;
}

bool LSM303DLHC::ReadMagnOnly(float *mx, float *my, float *mz) 
{
    char mag[6];
 
    if (recv(addr_mag, OUT_X_M, mag, 6)) 
    {
        *mx = float(short(mag[0] << 8 | mag[1]))/1100;
        //*mx = float(short(mag[0] << 8 | mag[1]))/450;
        //*mx = float(short(mag[0] << 8 | mag[1]));
        *mz = float(short(mag[2] << 8 | mag[3]))/980;
        //*mz = float(short(mag[2] << 8 | mag[3]))/400;
        //*mz = float(short(mag[2] << 8 | mag[3]));
        *my = float(short(mag[4] << 8 | mag[5]))/1100;
        //*my = float(short(mag[4] << 8 | mag[5]))/450;
        //*my = float(short(mag[4] << 8 | mag[5]));
 
        return true;
    }
 
    return false;
}

bool LSM303DLHC::recv(char sad, char sub, char *buf, int length) {
    if (length > 1) sub |= 0x80;
 
    return _LSM303.write(sad, &sub, 1, true) == 0 && _LSM303.read(sad, buf, length) == 0;
}
 
void LSM303DLHC::init(void)
{
    char reg_v;
    _LSM303.frequency(100000);
        
    reg_v = 0;
    
    reg_v |= 0x47;          // X/Y/Z axis enable. ODR set to 50 Hz
    write_reg(addr_acc,CTRL_REG1_A,reg_v);

    reg_v = 0;
   // reg_v |= 0x01 << 6;     /* 1: data MSB @ lower address */
    reg_v = 0x01 << 4;     /* +/- 4g */
    write_reg(addr_acc,CTRL_REG4_A,reg_v);

    /* -- mag --- */
    reg_v = 0;
    //leave line below commented for 0.75Hz data output rate (less noise)
    reg_v |= 0x04 << 2;     /* Minimum data output rate = 15Hz */
    write_reg(addr_mag,CRA_REG_M,reg_v);
    
    reg_v = 0;
    reg_v |= 0x01 << 5;     /* +-1.3Gauss */
    //reg_v |= 0x07 << 5;     /* +-8.1Gauss */
    write_reg(addr_mag,CRB_REG_M,reg_v);

    reg_v = 0;              /* Continuous-conversion mode */
    write_reg(addr_mag,MR_REG_M,reg_v);
}