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/*
* Author: Brendan Le Foll <brendan.le.foll@intel.com>
* Copyright (c) 2014 Intel Corporation.
*
* Code based on LSM303DLH sample by Jim Lindblom SparkFun Electronics
* and the CompensatedCompass.ino by Frankie Chu from SeedStudio
*
* 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.
*/
#include <iostream>
#include <string>
#include <stdexcept>
#include <unistd.h>
#include <stdlib.h>
#include "lsm303.h"
using namespace upm;
LSM303::LSM303(int bus, int addrMag, int addrAcc, int accScale) : m_i2c(bus)
{
m_addrMag = addrMag;
m_addrAcc = addrAcc;
// 0x27 is the 'normal' mode with X/Y/Z enable
setRegisterSafe(m_addrAcc, CTRL_REG1_A, 0x27);
// scale can be 2, 4 or 8
if (2 == accScale) {
setRegisterSafe(m_addrAcc, CTRL_REG4_A, 0x00);
} else if (4 == accScale) {
setRegisterSafe(m_addrAcc, CTRL_REG4_A, 0x10);
} else { // default; equivalent to 8g
setRegisterSafe(m_addrAcc, CTRL_REG4_A, 0x30);
}
// 0x10 = minimum datarate ~15Hz output rate
setRegisterSafe(m_addrMag, CRA_REG_M, 0x10);
// magnetic scale = +/-1.3
// Gaussmagnetic scale = +/-1.3Gauss (0x20)
// +-8.1Gauss (0xe0)
setRegisterSafe(m_addrMag, CRB_REG_M, 0xe0);
// 0x00 = continouous conversion mode
setRegisterSafe(m_addrMag, MR_REG_M, 0x00);
}
float
LSM303::getHeading()
{
if (getCoordinates() != mraa::SUCCESS) {
return -1;
}
float heading = 180.0 * atan2(double(coor[Y]), double(coor[X]))/M_PI;
if (heading < 0.0)
heading += 360.0;
return heading;
}
int16_t*
LSM303::getRawAccelData()
{
return &accel[0];
}
int16_t*
LSM303::getRawCoorData()
{
return &coor[0];
}
int16_t
LSM303::getAccelX()
{
return accel[X];
}
int16_t
LSM303::getAccelY()
{
return accel[Y];
}
int16_t
LSM303::getAccelZ()
{
return accel[Z];
}
mraa::Result
LSM303::getCoordinates()
{
mraa::Result ret = mraa::SUCCESS;
memset(&buf[0], 0, sizeof(uint8_t)*6);
ret = m_i2c.address(m_addrMag);
ret = m_i2c.writeByte(OUT_X_H_M);
ret = m_i2c.address(m_addrMag);
int num = m_i2c.read(buf, 6);
if (num != 6) {
return ret;
}
// convert to coordinates
for (int i=0; i<3; i++) {
coor[i] = (int16_t(buf[2*i] << 8))
| int16_t(buf[(2*i)+1]);
}
// swap elements 1 and 2 to get things in natural XYZ order
int16_t t = coor[2];
coor[2] = coor[1];
coor[1] = t;
//printf("X=%x, Y=%x, Z=%x\n", coor[X], coor[Y], coor[Z]);
return ret;
}
int16_t
LSM303::getCoorX() {
return coor[X];
}
int16_t
LSM303::getCoorY() {
return coor[Y];
}
int16_t
LSM303::getCoorZ() {
return coor[Z];
}
// helper function that writes a value to the acc and then reads
// FIX: shouldn't this be write-then-read?
int
LSM303::readThenWrite(uint8_t reg)
{
m_i2c.address(m_addrAcc);
m_i2c.writeByte(reg);
m_i2c.address(m_addrAcc);
return (int) m_i2c.readByte();
}
mraa::Result
LSM303::getAcceleration()
{
mraa::Result ret = mraa::SUCCESS;
accel[X] = (int16_t(readThenWrite(OUT_X_H_A)) << 8)
| int16_t(readThenWrite(OUT_X_L_A));
accel[Y] = (int16_t(readThenWrite(OUT_Y_H_A)) << 8)
| int16_t(readThenWrite(OUT_Y_L_A));
accel[Z] = (int16_t(readThenWrite(OUT_Z_H_A)) << 8)
| int16_t(readThenWrite(OUT_Z_L_A));
//printf("X=%x, Y=%x, Z=%x\n", accel[X], accel[Y], accel[Z]);
return ret;
}
// helper function that sets a register and then checks the set was succesful
mraa::Result
LSM303::setRegisterSafe(uint8_t slave, uint8_t sregister, uint8_t data)
{
buf[0] = sregister;
buf[1] = data;
if (m_i2c.address(slave) != mraa::SUCCESS) {
throw std::invalid_argument(std::string(__FUNCTION__) +
": mraa_i2c_address() failed");
return mraa::ERROR_INVALID_HANDLE;
}
if (m_i2c.write(buf, 2) != mraa::SUCCESS) {
throw std::invalid_argument(std::string(__FUNCTION__) +
": mraa_i2c_write() failed");
return mraa::ERROR_INVALID_HANDLE;
}
uint8_t val = m_i2c.readReg(sregister);
if (val != data) {
throw std::invalid_argument(std::string(__FUNCTION__) +
": failed to set register correctly");
return mraa::ERROR_UNSPECIFIED;
}
return mraa::SUCCESS;
}
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