File content as of revision 2:2645c4d75671:

/**
 * @author Aaron Berk
 * @author Serge Sozonoff
 * Partially based on the work of Aaron Berk for the HMC6352
 *
 * @section LICENSE
 *
 * Copyright (c) 2010 ARM Limited
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @section DESCRIPTION
 *
 * Honeywell HMC6343 tilt compensated digital compass.
 *
 * Datasheet:
 *
 * http://www.ssec.honeywell.com/magnetic/datasheets/HMC6343.pdf
 */

/**
 * Includes
 */
#include "HMC6343.h"

short h, r, p;

template<class TYPE> inline TYPE BIT(const TYPE & x) {
    return TYPE(1) << x;
}

template<class TYPE> inline bool IsBitSet(const TYPE & x, const TYPE & y) {
    return 0 != (x & y);
}

HMC6343::HMC6343(PinName sda, PinName scl) {
    i2c_ = new I2C(sda, scl);
    i2c_->frequency(100000);
    operationMode_ = getOpMode();
}

HMC6343::HMC6343(I2C& p_i2c) : i2c_(&p_i2c) {
    i2c_->frequency(100000);
    operationMode_ = getOpMode();
}

void HMC6343::sampleHeading(Heading* p_heading) {

    char tx[1];
    char rx[6];

    tx[0] = HMC6343_GET_HEADING_DATA;
    i2c_->write((HMC6343_I2C_ADDRESS << 1) & 0xFE, tx, 1);
    wait_ms(1);

    i2c_->read((HMC6343_I2C_ADDRESS << 1) | 0x01, rx, 6, true);
    
    h = ((((int)rx[0] << 8) | (int)rx[1]));
    r = ((((int)rx[4] << 8) | (int)rx[5]));
    p = ((((int)rx[2] << 8) | (int)rx[3]));

    p_heading->heading = (float)h / 10;
    p_heading->roll = (float)r / 10;
    p_heading->pitch = (float)p / 10;
}


void HMC6343::setReset(void) {
    char tx[1];
    tx[0] = HMC6343_RESET;
    i2c_->write((HMC6343_I2C_ADDRESS << 1) & 0xFE, tx, 1);
    wait_ms(500);
}

void HMC6343::setCalibrationMode(int exitOrEnter) {
    char tx[1];
    int delay = 0;

    tx[0] = exitOrEnter;

    if (exitOrEnter == HMC6343_EXIT_CALIB) {
        delay = 50;
    } else if (exitOrEnter == HMC6343_ENTER_CALIB) {
        delay = 1;
    }

    i2c_->write((HMC6343_I2C_ADDRESS << 1) & 0xFE, tx, 1);
    wait_ms(delay);
}

int HMC6343::getSlaveAddress(void) {
    return readEeprom(HMC6343_SLAVE_ADDR);
}

int HMC6343::getOffset(int axis) {

    char rx[2] = {0x00, 0x00};

    if (axis == HMC6343_X_AXIS) {
        rx[0] = readEeprom(HMC6343_XOFFSET_MSB);
        rx[1] = readEeprom(HMC6343_XOFFSET_LSB);

    } else if (axis == HMC6343_Y_AXIS) {
        rx[0] = readEeprom(HMC6343_YOFFSET_MSB);
        rx[1] = readEeprom(HMC6343_YOFFSET_LSB);

    } else {
        rx[0] = readEeprom(HMC6343_ZOFFSET_MSB);
        rx[1] = readEeprom(HMC6343_ZOFFSET_LSB);
    }

    return ((rx[0] << 8) | (rx[1]));

}

char HMC6343::getMeasurementRate() {
    if (IsBitSet(operationMode_, HMC6343_CM_MR_10HZ) && !IsBitSet(operationMode_, HMC6343_CM_MR_5HZ)) { return 10; }
    else if (IsBitSet(operationMode_, HMC6343_CM_MR_5HZ) && !IsBitSet(operationMode_, HMC6343_CM_MR_10HZ)) { return 5; }
    else return 1;
}

int HMC6343::getSoftwareVersion(void) {
    return readEeprom(HMC6343_SOFT_VER);
}

int HMC6343::getOpMode(void) {
    char tx[1];
    tx[0] = HMC6343_GET_OPMODE;

    char rx[2];

    i2c_->write((HMC6343_I2C_ADDRESS << 1) & 0xFE, tx, 1);
    wait_ms(1);
    i2c_->read((HMC6343_I2C_ADDRESS << 1) | 0x01, rx, 2, true);

    operationMode_ = (rx[1] << 8) | (rx[0]);

    return operationMode_;
}

bool HMC6343::isOpModeFlagSet(int flag) {
    return IsBitSet(operationMode_, flag);
}

void HMC6343::setOpMode(int opMode) {
    writeShort(HMC6343_OPMOD_REG1, (short)opMode);
    operationMode_ = getOpMode();
}

void HMC6343::writeShort(int lsb_address, short data) {
    writeEeprom(lsb_address, data & 0x00FF);
    writeEeprom(lsb_address + 1, data >> 8);
}

short HMC6343::readShort(int lsb_eprom_address) {
    return (short)(readEeprom(lsb_eprom_address + 1) << 8) | (readEeprom(lsb_eprom_address));
}

void HMC6343::setMagneticDeviation(float data) {
    short v;
    v = (short)(data * 100); // move decimal right two places
    if (v <= 1800 && v >= -1800) {
        writeShort(HMC6343_DEV_LSB, v);
    }
}

float HMC6343::getMagneticDeviation() {
    return (float)(readShort(HMC6343_DEV_LSB)) / 100;
}

void HMC6343::setMagneticVariation(float data) {
    short v;
    v = (short)(data * 100); // move decimal right two places
    if (v <= 1800 && v >= -1800) {
        writeShort(HMC6343_VAR_LSB, v);
    }
}

float HMC6343::getMagneticVariation() {
    return (float)(readShort(HMC6343_VAR_LSB)) / 100;
}

void HMC6343::setIIRFilter(short data) {
    writeShort(HMC6343_IIRF_LSB, data);
}

short HMC6343::getIIRFilter() {
    return (short)readShort(HMC6343_IIRF_LSB);
}

void HMC6343::setMagOffset(int axis, int offset) {
    if (axis == HMC6343_X_AXIS) {
        writeShort(HMC6343_XOFFSET_LSB, offset);
    } else if (axis == HMC6343_Y_AXIS) {
        writeShort(HMC6343_YOFFSET_LSB, offset);
    } else {
        writeShort(HMC6343_ZOFFSET_LSB, offset);
    }
}

int HMC6343::getMagOffset(int axis) {
    if (axis == HMC6343_X_AXIS) {
        return readShort(HMC6343_XOFFSET_LSB);
    } else if (axis == HMC6343_Y_AXIS) {
        return readShort(HMC6343_YOFFSET_LSB);
    } else {
        return readShort(HMC6343_ZOFFSET_LSB);
    }
}

void HMC6343::writeEeprom(int address, int data) {
    char tx[3];

    tx[0] = HMC6343_EEPROM_WRITE;
    tx[1] = address;
    tx[2] = data;

    i2c_->write((HMC6343_I2C_ADDRESS << 1) & 0xFE, tx, 3, false);
    wait_ms(10);
}

int HMC6343::readEeprom(int address) {
    char tx[2];
    char rx[1];

    tx[0] = HMC6343_EEPROM_READ;
    tx[1] = address;

    i2c_->write((HMC6343_I2C_ADDRESS << 1) & 0xFE, tx, 2, false);
    wait_ms(1);
    i2c_->read((HMC6343_I2C_ADDRESS << 1) | 0x01, rx, 1);
    wait_ms(1);

    return rx[0];
}