lsm303dlhc.h

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#ifndef LIBPROPELLER_LSM303DLHC_H_
#define LIBPROPELLER_LSM303DLHC_H_

#ifndef UNIT_TEST
#include "libpropeller/i2c/i2c.h"
#else
#include "libpropeller/i2c/i2cMOCK.h"
#endif

class LSM303DLHC {
public:

    LSM303DLHC() {
        bus_ = NULL;
        status_ = false;
    }

    bool Init(I2C * i2c_bus) {
        bus_ = i2c_bus;

        //Check to make sure the LSM303DLHC is actually there.
        status_ = bus_->Ping(kDeviceMagnAddress);
        if (status_ == false) {
            return false;
        }
        
        status_ = bus_->Ping(kDeviceAcclAddress);
        if (status_ == false) {
            return false;
        }


        //Initialize Magn
        bus_->Put(kDeviceMagnAddress, kCRA_REG_M, 0b10011100);
        bus_->Put(kDeviceMagnAddress, kCRB_REG_M, kGain_1_3);
        bus_->Put(kDeviceMagnAddress, kMR_REG_M, 0b00000000);

        //Initialize Accl
        bus_->Put(kDeviceAcclAddress, kCTRL_REG1_A, 0b10010111);
        bus_->Put(kDeviceAcclAddress, kCTRL_REG4_A, 0b00111000);

        return true;
    }

    bool ReadAccl(int& x, int& y, int& z) {
        char data[6];

        if (status_ == false) {
            x = y = z = 0;
            return false;
        }

        if (bus_->Get(kDeviceAcclAddress, kOUT_X_L_A, data, 6) == false) {
            x = y = z = 0;
            return false;
        }

        //16 + 4 = 20, or the 12 bit data given by the LSM303DLHC.
        //We are keeping the last 4 bits, and can divide them out later
        //(SRLM thinks the accl is only 12 bits, but the datasheet doesn't seem to
        //specify.
        x = ((data[0] | (data[1] << 8)) << 16) >> 16;
        y = ((data[2] | (data[3] << 8)) << 16) >> 16;
        z = ((data[4] | (data[5] << 8)) << 16) >> 16;

        return true;
    }

    bool ReadMagn(int& x, int& y, int& z) {
        char data[6];

        if (status_ == false) {
            x = y = z = 0;
            return false;
        }

        if (bus_->Get(kDeviceMagnAddress, kOUT_X_H_M, data, 6) == false) {
            x = y = z = 0;
            return false;
        }

        //Warning: the LSM303DLHC datasheet lists the magnetometer high registers
        //first, instead of the low (backwards compared to the accel and L3GD20).
        //Also note that the order of the parameters is XZY!
        x = ((data[1] | (data[0] << 8)) << 16) >> 16;
        z = ((data[3] | (data[2] << 8)) << 16) >> 16;
        y = ((data[5] | (data[4] << 8)) << 16) >> 16;

        return true;
    }

private:
    I2C * bus_;

    bool status_;

    const static unsigned char kDeviceAcclAddress = 0b00110010;
    const static unsigned char kDeviceMagnAddress = 0b00111100;

    //For the LSM303DLH Accl
    const static unsigned char kCTRL_REG1_A = 0x20;
    const static unsigned char kCTRL_REG4_A = 0x23;
    const static unsigned char kOUT_X_L_A = 0x28 | 0x80; //(turn on auto increment)

    //For the LSM303DLH Magn
    const static unsigned char kCRA_REG_M = 0x00;
    const static unsigned char kCRB_REG_M = 0x01;
    const static unsigned char kMR_REG_M = 0x02;
    const static unsigned char kOUT_X_H_M = 0x03 | 0x80; //(turn on auto increment)
    
    const static unsigned char kGain_1_9 = 0b01000000;
    const static unsigned char kGain_1_3 = 0b00100000;
};

#endif // LIBPROPELLER_LSM303DLHC_H_