/**
******************************************************************************
* @addtogroup PIOS PIOS Core hardware abstraction layer
* @{
* @addtogroup PIOS_HMC5883 HMC5883 Functions
* @brief Deals with the hardware interface to the magnetometers
* @{
* @file pios_hmc5883.c
* @author The OpenPilot Team, http://www.openpilot.org Copyright (C) 2012.
* @brief HMC5883 Magnetic Sensor Functions from AHRS
* @see The GNU Public License (GPL) Version 3
*
******************************************************************************
*/
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "pios.h"
#ifdef PIOS_INCLUDE_HMC5883
/* Global Variables */
/* Local Types */
/* Local Variables */
volatile bool pios_hmc5883_data_ready;
static int32_t PIOS_HMC5883_Config(const struct pios_hmc5883_cfg *cfg);
static int32_t PIOS_HMC5883_Read(uint8_t address, uint8_t *buffer, uint8_t len);
static int32_t PIOS_HMC5883_Write(uint8_t address, uint8_t buffer);
static const struct pios_hmc5883_cfg *dev_cfg;
/**
* @brief Initialize the HMC5883 magnetometer sensor.
* @return none
*/
void PIOS_HMC5883_Init(const struct pios_hmc5883_cfg *cfg)
{
dev_cfg = cfg; // store config before enabling interrupt
#ifdef PIOS_HMC5883_HAS_GPIOS
PIOS_EXTI_Init(cfg->exti_cfg);
#endif
int32_t val = PIOS_HMC5883_Config(cfg);
PIOS_Assert(val == 0);
pios_hmc5883_data_ready = false;
}
/**
* @brief Initialize the HMC5883 magnetometer sensor
* \return none
* \param[in] PIOS_HMC5883_ConfigTypeDef struct to be used to configure sensor.
*
* CTRL_REGA: Control Register A
* Read Write
* Default value: 0x10
* 7:5 0 These bits must be cleared for correct operation.
* 4:2 DO2-DO0: Data Output Rate Bits
* DO2 | DO1 | DO0 | Minimum Data Output Rate (Hz)
* ------------------------------------------------------
* 0 | 0 | 0 | 0.75
* 0 | 0 | 1 | 1.5
* 0 | 1 | 0 | 3
* 0 | 1 | 1 | 7.5
* 1 | 0 | 0 | 15 (default)
* 1 | 0 | 1 | 30
* 1 | 1 | 0 | 75
* 1 | 1 | 1 | Not Used
* 1:0 MS1-MS0: Measurement Configuration Bits
* MS1 | MS0 | MODE
* ------------------------------
* 0 | 0 | Normal
* 0 | 1 | Positive Bias
* 1 | 0 | Negative Bias
* 1 | 1 | Not Used
*
* CTRL_REGB: Control RegisterB
* Read Write
* Default value: 0x20
* 7:5 GN2-GN0: Gain Configuration Bits.
* GN2 | GN1 | GN0 | Mag Input | Gain | Output Range
* | | | Range[Ga] | [LSB/mGa] |
* ------------------------------------------------------
* 0 | 0 | 0 | ±0.88Ga | 1370 | 0xF8000x07FF (-2048:2047)
* 0 | 0 | 1 | ±1.3Ga (def) | 1090 | 0xF8000x07FF (-2048:2047)
* 0 | 1 | 0 | ±1.9Ga | 820 | 0xF8000x07FF (-2048:2047)
* 0 | 1 | 1 | ±2.5Ga | 660 | 0xF8000x07FF (-2048:2047)
* 1 | 0 | 0 | ±4.0Ga | 440 | 0xF8000x07FF (-2048:2047)
* 1 | 0 | 1 | ±4.7Ga | 390 | 0xF8000x07FF (-2048:2047)
* 1 | 1 | 0 | ±5.6Ga | 330 | 0xF8000x07FF (-2048:2047)
* 1 | 1 | 1 | ±8.1Ga | 230 | 0xF8000x07FF (-2048:2047)
* |Not recommended|
*
* 4:0 CRB4-CRB: 0 This bit must be cleared for correct operation.
*
* _MODE_REG: Mode Register
* Read Write
* Default value: 0x02
* 7:2 0 These bits must be cleared for correct operation.
* 1:0 MD1-MD0: Mode Select Bits
* MS1 | MS0 | MODE
* ------------------------------
* 0 | 0 | Continuous-Conversion Mode.
* 0 | 1 | Single-Conversion Mode
* 1 | 0 | Negative Bias
* 1 | 1 | Sleep Mode
*/
static uint8_t CTRLB = 0x00;
static int32_t PIOS_HMC5883_Config(const struct pios_hmc5883_cfg *cfg)
{
uint8_t CTRLA = 0x00;
uint8_t MODE = 0x00;
CTRLB = 0;
CTRLA |= (uint8_t)(cfg->M_ODR | cfg->Meas_Conf);
CTRLB |= (uint8_t)(cfg->Gain);
MODE |= (uint8_t)(cfg->Mode);
// CRTL_REGA
if (PIOS_HMC5883_Write(PIOS_HMC5883_CONFIG_REG_A, CTRLA) != 0) {
return -1;
}
// CRTL_REGB
if (PIOS_HMC5883_Write(PIOS_HMC5883_CONFIG_REG_B, CTRLB) != 0) {
return -1;
}
// Mode register
if (PIOS_HMC5883_Write(PIOS_HMC5883_MODE_REG, MODE) != 0) {
return -1;
}
return 0;
}
/**
* @brief Read current X, Z, Y values (in that order)
* \param[out] int16_t array of size 3 to store X, Z, and Y magnetometer readings
* \return 0 for success or -1 for failure
*/
int32_t PIOS_HMC5883_ReadMag(int16_t out[3])
{
pios_hmc5883_data_ready = false;
uint8_t buffer[6];
int32_t temp;
int32_t sensitivity;
if (PIOS_HMC5883_Read(PIOS_HMC5883_DATAOUT_XMSB_REG, buffer, 6) != 0) {
return -1;
}
switch (CTRLB & 0xE0) {
case 0x00:
sensitivity = PIOS_HMC5883_Sensitivity_0_88Ga;
break;
case 0x20:
sensitivity = PIOS_HMC5883_Sensitivity_1_3Ga;
break;
case 0x40:
sensitivity = PIOS_HMC5883_Sensitivity_1_9Ga;
break;
case 0x60:
sensitivity = PIOS_HMC5883_Sensitivity_2_5Ga;
break;
case 0x80:
sensitivity = PIOS_HMC5883_Sensitivity_4_0Ga;
break;
case 0xA0:
sensitivity = PIOS_HMC5883_Sensitivity_4_7Ga;
break;
case 0xC0:
sensitivity = PIOS_HMC5883_Sensitivity_5_6Ga;
break;
case 0xE0:
sensitivity = PIOS_HMC5883_Sensitivity_8_1Ga;
break;
default:
PIOS_Assert(0);
}
for (int i = 0; i < 3; i++) {
temp = ((int16_t)((uint16_t)buffer[2 * i] << 8)
+ buffer[2 * i + 1]) * 1000 / sensitivity;
out[i] = temp;
}
// Data reads out as X,Z,Y
temp = out[2];
out[2] = out[1];
out[1] = temp;
// This should not be necessary but for some reason it is coming out of continuous conversion mode
PIOS_HMC5883_Write(PIOS_HMC5883_MODE_REG, PIOS_HMC5883_MODE_CONTINUOUS);
return 0;
}
/**
* @brief Read the identification bytes from the HMC5883 sensor
* \param[out] uint8_t array of size 4 to store HMC5883 ID.
* \return 0 if successful, -1 if not
*/
uint8_t PIOS_HMC5883_ReadID(uint8_t out[4])
{
uint8_t retval = PIOS_HMC5883_Read(PIOS_HMC5883_DATAOUT_IDA_REG, out, 3);
out[3] = '\0';
return retval;
}
/**
* @brief Tells whether new magnetometer readings are available
* \return true if new data is available
* \return false if new data is not available
*/
bool PIOS_HMC5883_NewDataAvailable(void)
{
return pios_hmc5883_data_ready;
}
/**
* @brief Reads one or more bytes into a buffer
* \param[in] address HMC5883 register address (depends on size)
* \param[out] buffer destination buffer
* \param[in] len number of bytes which should be read
* \return 0 if operation was successful
* \return -1 if error during I2C transfer
* \return -2 if unable to claim i2c device
*/
static int32_t PIOS_HMC5883_Read(uint8_t address, uint8_t *buffer, uint8_t len)
{
uint8_t addr_buffer[] = {
address,
};
const struct pios_i2c_txn txn_list[] = {
{
.info = __func__,
.addr = PIOS_HMC5883_I2C_ADDR,
.rw = PIOS_I2C_TXN_WRITE,
.len = sizeof(addr_buffer),
.buf = addr_buffer,
}
,
{
.info = __func__,
.addr = PIOS_HMC5883_I2C_ADDR,
.rw = PIOS_I2C_TXN_READ,
.len = len,
.buf = buffer,
}
};
return PIOS_I2C_Transfer(PIOS_I2C_MAIN_ADAPTER, txn_list, NELEMENTS(txn_list));
}
/**
* @brief Writes one or more bytes to the HMC5883
* \param[in] address Register address
* \param[in] buffer source buffer
* \return 0 if operation was successful
* \return -1 if error during I2C transfer
* \return -2 if unable to claim i2c device
*/
static int32_t PIOS_HMC5883_Write(uint8_t address, uint8_t buffer)
{
uint8_t data[] = {
address,
buffer,
};
const struct pios_i2c_txn txn_list[] = {
{
.info = __func__,
.addr = PIOS_HMC5883_I2C_ADDR,
.rw = PIOS_I2C_TXN_WRITE,
.len = sizeof(data),
.buf = data,
}
,
};
;
return PIOS_I2C_Transfer(PIOS_I2C_MAIN_ADAPTER, txn_list, NELEMENTS(txn_list));
}
/**
* @brief Run self-test operation. Do not call this during operational use!!
* \return 0 if success, -1 if test failed
*/
int32_t PIOS_HMC5883_Test(void)
{
int32_t failed = 0;
uint8_t registers[3] = { 0, 0, 0 };
uint8_t status;
uint8_t ctrl_a_read;
uint8_t ctrl_b_read;
uint8_t mode_read;
int16_t values[3];
/* Verify that ID matches (HMC5883 ID is null-terminated ASCII string "H43") */
char id[4];
PIOS_HMC5883_ReadID((uint8_t *)id);
if ((id[0] != 'H') || (id[1] != '4') || (id[2] != '3')) { // Expect H43
return -1;
}
/* Backup existing configuration */
if (PIOS_HMC5883_Read(PIOS_HMC5883_CONFIG_REG_A, registers, 3) != 0) {
return -1;
}
/* Stop the device and read out last value */
PIOS_DELAY_WaitmS(10);
if (PIOS_HMC5883_Write(PIOS_HMC5883_MODE_REG, PIOS_HMC5883_MODE_IDLE) != 0) {
return -1;
}
if (PIOS_HMC5883_Read(PIOS_HMC5883_DATAOUT_STATUS_REG, &status, 1) != 0) {
return -1;
}
if (PIOS_HMC5883_ReadMag(values) != 0) {
return -1;
}
/*
* Put HMC5883 into self test mode
* This is done by placing measurement config into positive (0x01) or negative (0x10) bias
* and then placing the mode register into single-measurement mode. This causes the HMC5883
* to create an artificial magnetic field of ~1.1 Gauss.
*
* If gain were PIOS_HMC5883_GAIN_2_5, for example, X and Y will read around +766 LSB
* (1.16 Ga * 660 LSB/Ga) and Z would read around +713 LSB (1.08 Ga * 660 LSB/Ga)
*
* Changing measurement config back to PIOS_HMC5883_MEASCONF_NORMAL will leave self-test mode.
*/
PIOS_DELAY_WaitmS(10);
if (PIOS_HMC5883_Write(PIOS_HMC5883_CONFIG_REG_A, PIOS_HMC5883_MEASCONF_BIAS_POS | PIOS_HMC5883_ODR_15) != 0) {
return -1;
}
PIOS_DELAY_WaitmS(10);
if (PIOS_HMC5883_Write(PIOS_HMC5883_CONFIG_REG_B, PIOS_HMC5883_GAIN_8_1) != 0) {
return -1;
}
PIOS_DELAY_WaitmS(10);
if (PIOS_HMC5883_Write(PIOS_HMC5883_MODE_REG, PIOS_HMC5883_MODE_SINGLE) != 0) {
return -1;
}
/* Must wait for value to be updated */
PIOS_DELAY_WaitmS(200);
if (PIOS_HMC5883_ReadMag(values) != 0) {
return -1;
}
/*
if(abs(values[0] - 766) > 20)
failed |= 1;
if(abs(values[1] - 766) > 20)
failed |= 1;
if(abs(values[2] - 713) > 20)
failed |= 1;
*/
PIOS_HMC5883_Read(PIOS_HMC5883_CONFIG_REG_A, &ctrl_a_read, 1);
PIOS_HMC5883_Read(PIOS_HMC5883_CONFIG_REG_B, &ctrl_b_read, 1);
PIOS_HMC5883_Read(PIOS_HMC5883_MODE_REG, &mode_read, 1);
PIOS_HMC5883_Read(PIOS_HMC5883_DATAOUT_STATUS_REG, &status, 1);
/* Restore backup configuration */
PIOS_DELAY_WaitmS(10);
if (PIOS_HMC5883_Write(PIOS_HMC5883_CONFIG_REG_A, registers[0]) != 0) {
return -1;
}
PIOS_DELAY_WaitmS(10);
if (PIOS_HMC5883_Write(PIOS_HMC5883_CONFIG_REG_B, registers[1]) != 0) {
return -1;
}
PIOS_DELAY_WaitmS(10);
if (PIOS_HMC5883_Write(PIOS_HMC5883_MODE_REG, registers[2]) != 0) {
return -1;
}
return failed;
}
/**
* @brief IRQ Handler
*/
bool PIOS_HMC5883_IRQHandler(void)
{
pios_hmc5883_data_ready = true;
return false;
}
#endif /* PIOS_INCLUDE_HMC5883 */
/**
* @}
* @}
*/