/** ****************************************************************************** * @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) 2011. * @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 */ /* Project Includes */ #include "pios.h" #if defined(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 /* Configure EOC pin as input floating */ GPIO_Init(cfg->drdy.gpio, &cfg->drdy.init); /* Configure the End Of Conversion (EOC) interrupt */ SYSCFG_EXTILineConfig(cfg->eoc_exti.port_source, cfg->eoc_exti.pin_source); EXTI_Init(&cfg->eoc_exti.init); /* Enable and set EOC EXTI Interrupt to the lowest priority */ NVIC_Init(&cfg->eoc_irq.init); 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 | 0xF800–0x07FF (-2048:2047) * 0 | 0 | 1 | ±1.3Ga (def) | 1090 | 0xF800–0x07FF (-2048:2047) * 0 | 1 | 0 | ±1.9Ga | 820 | 0xF800–0x07FF (-2048:2047) * 0 | 1 | 1 | ±2.5Ga | 660 | 0xF800–0x07FF (-2048:2047) * 1 | 0 | 0 | ±4.0Ga | 440 | 0xF800–0x07FF (-2048:2047) * 1 | 0 | 1 | ±4.7Ga | 390 | 0xF800–0x07FF (-2048:2047) * 1 | 1 | 0 | ±5.6Ga | 330 | 0xF800–0x07FF (-2048:2047) * 1 | 1 | 1 | ±8.1Ga | 230 | 0xF800–0x07FF (-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 */ uint32_t fail = 0; uint32_t succeed = 0; 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) { fail++; return -1; } succeed++; 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 */ void PIOS_HMC5883_IRQHandler(void) { pios_hmc5883_data_ready = true; } /** * The physical IRQ handler * Soon this will be generic in pios_exti and the BMA180 will register * against it. Right now this is crap! */ uint32_t count = 0; uint32_t count2 = 0; void EXTI9_5_IRQHandler(void) { count++; if (EXTI_GetITStatus(dev_cfg->eoc_exti.init.EXTI_Line) != RESET) { count2++; PIOS_HMC5883_IRQHandler(); EXTI_ClearITPendingBit(dev_cfg->eoc_exti.init.EXTI_Line); } } #endif /* PIOS_INCLUDE_HMC5883 */ /** * @} * @} */