20160814
Fork of LSM9DS0 by
LSM9DS0.cpp
- Committer:
- YCTung
- Date:
- 2016-02-26
- Revision:
- 0:0dbf7ee73651
- Child:
- 1:2c34ccab5256
File content as of revision 0:0dbf7ee73651:
//Original author /****************************************************************************** SFE_LSM9DS0.cpp SFE_LSM9DS0 Library Source File Jim Lindblom @ SparkFun Electronics Original Creation Date: February 14, 2014 (Happy Valentines Day!) https://github.com/sparkfun/LSM9DS0_Breakout This file implements all functions of the LSM9DS0 class. Functions here range from higher level stuff, like reading/writing LSM9DS0 registers to low-level, hardware reads and writes. Both SPI and I2C handler functions can be found towards the bottom of this file. Development environment specifics: IDE: Arduino 1.0.5 Hardware Platform: Arduino Pro 3.3V/8MHz LSM9DS0 Breakout Version: 1.0 This code is beerware; if you see me (or any other SparkFun employee) at the local, and you've found our code helpful, please buy us a round! Distributed as-is; no warranty is given. ******************************************************************************/ #include "LSM9DS0.h" #include "mbed.h" //I2C i2c(D14,D15); //SPI spi(D4,D5,D3); //****************************************************************************// // // LSM9DS0 functions. // // Construction arguments: // (interface_mode interface, uint8_t gAddr, uint8_t xmAddr ), // // where gAddr and xmAddr are addresses for I2C_MODE and chip select pin // number for SPI_MODE // // For SPI, construct LSM6DS3 myIMU(SPI_MODE, D9, D6); // //================================= LSM9DS0::LSM9DS0(interface_mode interface, uint8_t gAddr, uint8_t xmAddr) : interfaceMode(SPI_MODE), spi_(D4,D5,D3), i2c_(I2C_SDA,I2C_SCL), csG_(D9), csXM_(D6) { // interfaceMode will keep track of whether we're using SPI or I2C: interfaceMode = interface; // xmAddress and gAddress will store the 7-bit I2C address, if using I2C. // If we're using SPI, these variables store the chip-select pins. gAddress = gAddr; xmAddress = xmAddr; } uint16_t LSM9DS0::begin(gyro_scale gScl, accel_scale aScl, mag_scale mScl, gyro_odr gODR, accel_odr aODR, mag_odr mODR) { // Store the given scales in class variables. These scale variables // are used throughout to calculate the actual g's, DPS,and Gs's. gScale = gScl; aScale = aScl; mScale = mScl; // Once we have the scale values, we can calculate the resolution // of each sensor. That's what these functions are for. One for each sensor calcgRes(); // Calculate DPS / ADC tick, stored in gRes variable calcmRes(); // Calculate Gs / ADC tick, stored in mRes variable calcaRes(); // Calculate g / ADC tick, stored in aRes variable // Now, initialize our hardware interface. if (interfaceMode == I2C_MODE) // If we're using I2C initI2C(); // Initialize I2C else if (interfaceMode == SPI_MODE) // else, if we're using SPI initSPI(); // Initialize SPI // To verify communication, we can read from the WHO_AM_I register of // each device. Store those in a variable so we can return them. uint8_t gTest = gReadByte(WHO_AM_I_G); // Read the gyro WHO_AM_I uint8_t xmTest = xmReadByte(WHO_AM_I_XM); // Read the accel/mag WHO_AM_I // Gyro initialization stuff: initGyro(); // This will "turn on" the gyro. Setting up interrupts, etc. setGyroODR(gODR); // Set the gyro output data rate and bandwidth. setGyroScale(gScale); // Set the gyro range // Accelerometer initialization stuff: initAccel(); // "Turn on" all axes of the accel. Set up interrupts, etc. setAccelODR(aODR); // Set the accel data rate. setAccelScale(aScale); // Set the accel range. // Magnetometer initialization stuff: initMag(); // "Turn on" all axes of the mag. Set up interrupts, etc. setMagODR(mODR); // Set the magnetometer output data rate. setMagScale(mScale); // Set the magnetometer's range. // Once everything is initialized, return the WHO_AM_I registers we read: return (xmTest << 8) | gTest; } void LSM9DS0::initGyro() { /* CTRL_REG1_G sets output data rate, bandwidth, power-down and enables Bits[7:0]: DR1 DR0 BW1 BW0 PD Zen Xen Yen DR[1:0] - Output data rate selection 00=95Hz, 01=190Hz, 10=380Hz, 11=760Hz BW[1:0] - Bandwidth selection (sets cutoff frequency) Value depends on ODR. See datasheet table 21. PD - Power down enable (0=power down mode, 1=normal or sleep mode) Zen, Xen, Yen - Axis enable (o=disabled, 1=enabled) */ gWriteByte(CTRL_REG1_G, 0xFF); // Normal mode, enable all axes /* CTRL_REG2_G sets up the HPF Bits[7:0]: 0 0 HPM1 HPM0 HPCF3 HPCF2 HPCF1 HPCF0 HPM[1:0] - High pass filter mode selection 00=normal (reset reading HP_RESET_FILTER, 01=ref signal for filtering, 10=normal, 11=autoreset on interrupt HPCF[3:0] - High pass filter cutoff frequency Value depends on data rate. See datasheet table 26. */ gWriteByte(CTRL_REG2_G, 0x09); // Normal mode, high cutoff frequency /* CTRL_REG3_G sets up interrupt and DRDY_G pins Bits[7:0]: I1_IINT1 I1_BOOT H_LACTIVE PP_OD I2_DRDY I2_WTM I2_ORUN I2_EMPTY I1_INT1 - Interrupt enable on INT_G pin (0=disable, 1=enable) I1_BOOT - Boot status available on INT_G (0=disable, 1=enable) H_LACTIVE - Interrupt active configuration on INT_G (0:high, 1:low) PP_OD - Push-pull/open-drain (0=push-pull, 1=open-drain) I2_DRDY - Data ready on DRDY_G (0=disable, 1=enable) I2_WTM - FIFO watermark interrupt on DRDY_G (0=disable 1=enable) I2_ORUN - FIFO overrun interrupt on DRDY_G (0=disable 1=enable) I2_EMPTY - FIFO empty interrupt on DRDY_G (0=disable 1=enable) */ // Int1 enabled (pp, active low), data read on DRDY_G: gWriteByte(CTRL_REG3_G, 0x00); /* CTRL_REG4_G sets the scale, update mode Bits[7:0] - BDU BLE FS1 FS0 - ST1 ST0 SIM BDU - Block data update (0=continuous, 1=output not updated until read BLE - Big/little endian (0=data LSB @ lower address, 1=LSB @ higher add) FS[1:0] - Full-scale selection 00=245dps, 01=500dps, 10=2000dps, 11=2000dps ST[1:0] - Self-test enable 00=disabled, 01=st 0 (x+, y-, z-), 10=undefined, 11=st 1 (x-, y+, z+) SIM - SPI serial interface mode select 0=4 wire, 1=3 wire */ gWriteByte(CTRL_REG4_G, 0x30); // Set scale to 245 dps /* CTRL_REG5_G sets up the FIFO, HPF, and INT1 Bits[7:0] - BOOT FIFO_EN - HPen INT1_Sel1 INT1_Sel0 Out_Sel1 Out_Sel0 BOOT - Reboot memory content (0=normal, 1=reboot) FIFO_EN - FIFO enable (0=disable, 1=enable) HPen - HPF enable (0=disable, 1=enable) INT1_Sel[1:0] - Int 1 selection configuration Out_Sel[1:0] - Out selection configuration */ gWriteByte(CTRL_REG5_G, 0x00); // Temporary !!! For testing !!! Remove !!! Or make useful !!! configGyroInt(0x2A, 0, 0, 0, 0); // Trigger interrupt when above 0 DPS... } void LSM9DS0::initAccel() { /* CTRL_REG0_XM (0x1F) (Default value: 0x00) Bits (7-0): BOOT FIFO_EN WTM_EN 0 0 HP_CLICK HPIS1 HPIS2 BOOT - Reboot memory content (0: normal, 1: reboot) FIFO_EN - Fifo enable (0: disable, 1: enable) WTM_EN - FIFO watermark enable (0: disable, 1: enable) HP_CLICK - HPF enabled for click (0: filter bypassed, 1: enabled) HPIS1 - HPF enabled for interrupt generator 1 (0: bypassed, 1: enabled) HPIS2 - HPF enabled for interrupt generator 2 (0: bypassed, 1 enabled) */ xmWriteByte(CTRL_REG0_XM, 0x00); /* CTRL_REG1_XM (0x20) (Default value: 0x07) Bits (7-0): AODR3 AODR2 AODR1 AODR0 BDU AZEN AYEN AXEN AODR[3:0] - select the acceleration data rate: 0000=power down, 0001=3.125Hz, 0010=6.25Hz, 0011=12.5Hz, 0100=25Hz, 0101=50Hz, 0110=100Hz, 0111=200Hz, 1000=400Hz, 1001=800Hz, 1010=1600Hz, (remaining combinations undefined). BDU - block data update for accel AND mag 0: Continuous update 1: Output registers aren't updated until MSB and LSB have been read. AZEN, AYEN, and AXEN - Acceleration x/y/z-axis enabled. 0: Axis disabled, 1: Axis enabled */ xmWriteByte(CTRL_REG1_XM, 0x97); // 100Hz data rate, x/y/z all enabled //Serial.println(xmReadByte(CTRL_REG1_XM)); /* CTRL_REG2_XM (0x21) (Default value: 0x00) Bits (7-0): ABW1 ABW0 AFS2 AFS1 AFS0 AST1 AST0 SIM ABW[1:0] - Accelerometer anti-alias filter bandwidth 00=773Hz, 01=194Hz, 10=362Hz, 11=50Hz AFS[2:0] - Accel full-scale selection 000=+/-2g, 001=+/-4g, 010=+/-6g, 011=+/-8g, 100=+/-16g AST[1:0] - Accel self-test enable 00=normal (no self-test), 01=positive st, 10=negative st, 11=not allowed SIM - SPI mode selection 0=4-wire, 1=3-wire */ xmWriteByte(CTRL_REG2_XM, 0xD8); // Set scale to 2g /* CTRL_REG3_XM is used to set interrupt generators on INT1_XM Bits (7-0): P1_BOOT P1_TAP P1_INT1 P1_INT2 P1_INTM P1_DRDYA P1_DRDYM P1_EMPTY */ // Accelerometer data ready on INT1_XM (0x04) xmWriteByte(CTRL_REG3_XM, 0x00); } void LSM9DS0::initMag() { /* CTRL_REG5_XM enables temp sensor, sets mag resolution and data rate Bits (7-0): TEMP_EN M_RES1 M_RES0 M_ODR2 M_ODR1 M_ODR0 LIR2 LIR1 TEMP_EN - Enable temperature sensor (0=disabled, 1=enabled) M_RES[1:0] - Magnetometer resolution select (0=low, 3=high) M_ODR[2:0] - Magnetometer data rate select 000=3.125Hz, 001=6.25Hz, 010=12.5Hz, 011=25Hz, 100=50Hz, 101=100Hz LIR2 - Latch interrupt request on INT2_SRC (cleared by reading INT2_SRC) 0=interrupt request not latched, 1=interrupt request latched LIR1 - Latch interrupt request on INT1_SRC (cleared by readging INT1_SRC) 0=irq not latched, 1=irq latched */ xmWriteByte(CTRL_REG5_XM, 0x74); // Mag data rate - 100 Hz, disable temperature sensor /* CTRL_REG6_XM sets the magnetometer full-scale Bits (7-0): 0 MFS1 MFS0 0 0 0 0 0 MFS[1:0] - Magnetic full-scale selection 00:+/-2Gauss, 01:+/-4Gs, 10:+/-8Gs, 11:+/-12Gs */ xmWriteByte(CTRL_REG6_XM, 0x40); // Mag scale to +/- 2GS /* CTRL_REG7_XM sets magnetic sensor mode, low power mode, and filters AHPM1 AHPM0 AFDS 0 0 MLP MD1 MD0 AHPM[1:0] - HPF mode selection 00=normal (resets reference registers), 01=reference signal for filtering, 10=normal, 11=autoreset on interrupt event AFDS - Filtered acceleration data selection 0=internal filter bypassed, 1=data from internal filter sent to FIFO MLP - Magnetic data low-power mode 0=data rate is set by M_ODR bits in CTRL_REG5 1=data rate is set to 3.125Hz MD[1:0] - Magnetic sensor mode selection (default 10) 00=continuous-conversion, 01=single-conversion, 10 and 11=power-down */ xmWriteByte(CTRL_REG7_XM, 0x00); // Continuous conversion mode /* CTRL_REG4_XM is used to set interrupt generators on INT2_XM Bits (7-0): P2_TAP P2_INT1 P2_INT2 P2_INTM P2_DRDYA P2_DRDYM P2_Overrun P2_WTM */ xmWriteByte(CTRL_REG4_XM, 0x00); // Magnetometer data ready on INT2_XM (0x08) /* INT_CTRL_REG_M to set push-pull/open drain, and active-low/high Bits[7:0] - XMIEN YMIEN ZMIEN PP_OD IEA IEL 4D MIEN XMIEN, YMIEN, ZMIEN - Enable interrupt recognition on axis for mag data PP_OD - Push-pull/open-drain interrupt configuration (0=push-pull, 1=od) IEA - Interrupt polarity for accel and magneto 0=active-low, 1=active-high IEL - Latch interrupt request for accel and magneto 0=irq not latched, 1=irq latched 4D - 4D enable. 4D detection is enabled when 6D bit in INT_GEN1_REG is set MIEN - Enable interrupt generation for magnetic data 0=disable, 1=enable) */ xmWriteByte(INT_CTRL_REG_M, 0x09); // Enable interrupts for mag, active-low, push-pull } // This is a function that uses the FIFO to accumulate sample of accelerometer and gyro data, average // them, scales them to gs and deg/s, respectively, and then passes the biases to the main sketch // for subtraction from all subsequent data. There are no gyro and accelerometer bias registers to store // the data as there are in the ADXL345, a precursor to the LSM9DS0, or the MPU-9150, so we have to // subtract the biases ourselves. This results in a more accurate measurement in general and can // remove errors due to imprecise or varying initial placement. Calibration of sensor data in this manner // is good practice. void LSM9DS0::calLSM9DS0(float * gbias, float * abias) { uint8_t data[6] = {0, 0, 0, 0, 0, 0}; int16_t gyro_bias[3] = {0, 0, 0}, accel_bias[3] = {0, 0, 0}; int samples, ii; // First get gyro bias uint8_t c = gReadByte(CTRL_REG5_G); gWriteByte(CTRL_REG5_G, c | 0x40); // Enable gyro FIFO wait_ms(20); // Wait for change to take effect gWriteByte(FIFO_CTRL_REG_G, 0x20 | 0x1F); // Enable gyro FIFO stream mode and set watermark at 32 samples wait_ms(1000); // delay 1000 milliseconds to collect FIFO samples samples = (gReadByte(FIFO_SRC_REG_G) & 0x1F); // Read number of stored samples for(ii = 0; ii < samples ; ii++) { // Read the gyro data stored in the FIFO gReadBytes(OUT_X_L_G, &data[0], 6); gyro_bias[0] += (((int16_t)data[1] << 8) | data[0]); gyro_bias[1] += (((int16_t)data[3] << 8) | data[2]); gyro_bias[2] += (((int16_t)data[5] << 8) | data[4]); } gyro_bias[0] /= samples; // average the data gyro_bias[1] /= samples; gyro_bias[2] /= samples; gbias[0] = (float)gyro_bias[0]*gRes; // Properly scale the data to get deg/s gbias[1] = (float)gyro_bias[1]*gRes; gbias[2] = (float)gyro_bias[2]*gRes; c = gReadByte(CTRL_REG5_G); gWriteByte(CTRL_REG5_G, c & ~0x40); // Disable gyro FIFO wait_ms(20); gWriteByte(FIFO_CTRL_REG_G, 0x00); // Enable gyro bypass mode // Now get the accelerometer biases c = xmReadByte(CTRL_REG0_XM); xmWriteByte(CTRL_REG0_XM, c | 0x40); // Enable accelerometer FIFO wait_ms(20); // Wait for change to take effect xmWriteByte(FIFO_CTRL_REG, 0x20 | 0x1F); // Enable accelerometer FIFO stream mode and set watermark at 32 samples wait_ms(1000); // delay 1000 milliseconds to collect FIFO samples samples = (xmReadByte(FIFO_SRC_REG) & 0x1F); // Read number of stored accelerometer samples for(ii = 0; ii < samples ; ii++) { // Read the accelerometer data stored in the FIFO xmReadBytes(OUT_X_L_A, &data[0], 6); accel_bias[0] += (((int16_t)data[1] << 8) | data[0]); accel_bias[1] += (((int16_t)data[3] << 8) | data[2]); accel_bias[2] += (((int16_t)data[5] << 8) | data[4]) - (int16_t)(1.0f/aRes); // Assumes sensor facing up! } accel_bias[0] /= samples; // average the data accel_bias[1] /= samples; accel_bias[2] /= samples; abias[0] = (float)accel_bias[0]*aRes; // Properly scale data to get gs abias[1] = (float)accel_bias[1]*aRes; abias[2] = (float)accel_bias[2]*aRes; c = xmReadByte(CTRL_REG0_XM); xmWriteByte(CTRL_REG0_XM, c & ~0x40); // Disable accelerometer FIFO wait_ms(20); xmWriteByte(FIFO_CTRL_REG, 0x00); // Enable accelerometer bypass mode } void LSM9DS0::readAccel() { uint8_t temp[6]; // We'll read six bytes from the accelerometer into temp xmReadBytes(OUT_X_L_A, temp, 6); // Read 6 bytes, beginning at OUT_X_L_A ax = (temp[1] << 8) | temp[0]; // Store x-axis values into ax ay = (temp[3] << 8) | temp[2]; // Store y-axis values into ay az = (temp[5] << 8) | temp[4]; // Store z-axis values into az } void LSM9DS0::readMag() { uint8_t temp[6]; // We'll read six bytes from the mag into temp xmReadBytes(OUT_X_L_M, temp, 6); // Read 6 bytes, beginning at OUT_X_L_M mx = (temp[1] << 8) | temp[0]; // Store x-axis values into mx my = (temp[3] << 8) | temp[2]; // Store y-axis values into my mz = (temp[5] << 8) | temp[4]; // Store z-axis values into mz } void LSM9DS0::readTemp() { uint8_t temp[2]; // We'll read two bytes from the temperature sensor into temp xmReadBytes(OUT_TEMP_L_XM, temp, 2); // Read 2 bytes, beginning at OUT_TEMP_L_M temperature = (((int16_t) temp[1] << 12) | temp[0] << 4 ) >> 4; // Temperature is a 12-bit signed integer } void LSM9DS0::readGyro() { uint8_t temp[6]; // We'll read six bytes from the gyro into temp gReadBytes(OUT_X_L_G, temp, 6); // Read 6 bytes, beginning at OUT_X_L_G gx = (temp[1] << 8) | temp[0]; // Store x-axis values into gx gy = (temp[3] << 8) | temp[2]; // Store y-axis values into gy gz = (temp[5] << 8) | temp[4]; // Store z-axis values into gz } float LSM9DS0::calcGyro(int16_t gyro) { // Return the gyro raw reading times our pre-calculated DPS / (ADC tick): return gRes * gyro; } float LSM9DS0::calcAccel(int16_t accel) { // Return the accel raw reading times our pre-calculated g's / (ADC tick): return aRes * accel; } float LSM9DS0::calcMag(int16_t mag) { // Return the mag raw reading times our pre-calculated Gs / (ADC tick): return mRes * mag; } void LSM9DS0::setGyroScale(gyro_scale gScl) { // We need to preserve the other bytes in CTRL_REG4_G. So, first read it: uint8_t temp = gReadByte(CTRL_REG4_G); // Then mask out the gyro scale bits: temp &= 0xFF^(0x3 << 4); // Then shift in our new scale bits: temp |= gScl << 4; // And write the new register value back into CTRL_REG4_G: gWriteByte(CTRL_REG4_G, temp); // We've updated the sensor, but we also need to update our class variables // First update gScale: gScale = gScl; // Then calculate a new gRes, which relies on gScale being set correctly: calcgRes(); } void LSM9DS0::setAccelScale(accel_scale aScl) { // We need to preserve the other bytes in CTRL_REG2_XM. So, first read it: uint8_t temp = xmReadByte(CTRL_REG2_XM); // Then mask out the accel scale bits: temp &= 0xFF^(0x7 << 3); // Then shift in our new scale bits: temp |= aScl << 3; // And write the new register value back into CTRL_REG2_XM: xmWriteByte(CTRL_REG2_XM, temp); // We've updated the sensor, but we also need to update our class variables // First update aScale: aScale = aScl; // Then calculate a new aRes, which relies on aScale being set correctly: calcaRes(); } void LSM9DS0::setMagScale(mag_scale mScl) { // We need to preserve the other bytes in CTRL_REG6_XM. So, first read it: uint8_t temp = xmReadByte(CTRL_REG6_XM); // Then mask out the mag scale bits: temp &= 0xFF^(0x3 << 5); // Then shift in our new scale bits: temp |= mScl << 5; // And write the new register value back into CTRL_REG6_XM: xmWriteByte(CTRL_REG6_XM, temp); // We've updated the sensor, but we also need to update our class variables // First update mScale: mScale = mScl; // Then calculate a new mRes, which relies on mScale being set correctly: calcmRes(); } void LSM9DS0::setGyroODR(gyro_odr gRate) { // We need to preserve the other bytes in CTRL_REG1_G. So, first read it: uint8_t temp = gReadByte(CTRL_REG1_G); // Then mask out the gyro ODR bits: temp &= 0xFF^(0xF << 4); // Then shift in our new ODR bits: temp |= (gRate << 4); // And write the new register value back into CTRL_REG1_G: gWriteByte(CTRL_REG1_G, temp); } void LSM9DS0::setAccelODR(accel_odr aRate) { // We need to preserve the other bytes in CTRL_REG1_XM. So, first read it: uint8_t temp = xmReadByte(CTRL_REG1_XM); // Then mask out the accel ODR bits: temp &= 0xFF^(0xF << 4); // Then shift in our new ODR bits: temp |= (aRate << 4); // And write the new register value back into CTRL_REG1_XM: xmWriteByte(CTRL_REG1_XM, temp); } void LSM9DS0::setAccelABW(accel_abw abwRate) { // We need to preserve the other bytes in CTRL_REG2_XM. So, first read it: uint8_t temp = xmReadByte(CTRL_REG2_XM); // Then mask out the accel ABW bits: temp &= 0xFF^(0x3 << 6); // Then shift in our new ODR bits: temp |= (abwRate << 6); // And write the new register value back into CTRL_REG2_XM: xmWriteByte(CTRL_REG2_XM, temp); } void LSM9DS0::setMagODR(mag_odr mRate) { // We need to preserve the other bytes in CTRL_REG5_XM. So, first read it: uint8_t temp = xmReadByte(CTRL_REG5_XM); // Then mask out the mag ODR bits: temp &= 0xFF^(0x7 << 2); // Then shift in our new ODR bits: temp |= (mRate << 2); // And write the new register value back into CTRL_REG5_XM: xmWriteByte(CTRL_REG5_XM, temp); } void LSM9DS0::configGyroInt(uint8_t int1Cfg, uint16_t int1ThsX, uint16_t int1ThsY, uint16_t int1ThsZ, uint8_t duration) { gWriteByte(INT1_CFG_G, int1Cfg); gWriteByte(INT1_THS_XH_G, (int1ThsX & 0xFF00) >> 8); gWriteByte(INT1_THS_XL_G, (int1ThsX & 0xFF)); gWriteByte(INT1_THS_YH_G, (int1ThsY & 0xFF00) >> 8); gWriteByte(INT1_THS_YL_G, (int1ThsY & 0xFF)); gWriteByte(INT1_THS_ZH_G, (int1ThsZ & 0xFF00) >> 8); gWriteByte(INT1_THS_ZL_G, (int1ThsZ & 0xFF)); if (duration) gWriteByte(INT1_DURATION_G, 0x80 | duration); else gWriteByte(INT1_DURATION_G, 0x00); } void LSM9DS0::calcgRes() { // Possible gyro scales (and their register bit settings) are: // 245 DPS (00), 500 DPS (01), 2000 DPS (10). Here's a bit of an algorithm // to calculate DPS/(ADC tick) based on that 2-bit value: switch (gScale) { case G_SCALE_245DPS: gRes = 245.0 / 32768.0; break; case G_SCALE_500DPS: gRes = 500.0 / 32768.0; break; case G_SCALE_2000DPS: gRes = 2000.0 / 32768.0; break; } } void LSM9DS0::calcaRes() { // Possible accelerometer scales (and their register bit settings) are: // 2 g (000), 4g (001), 6g (010) 8g (011), 16g (100). Here's a bit of an // algorithm to calculate g/(ADC tick) based on that 3-bit value: aRes = aScale == A_SCALE_16G ? 16.0 / 32768.0 : (((float) aScale + 1.0f) * 2.0f) / 32768.0f; } void LSM9DS0::calcmRes() { // Possible magnetometer scales (and their register bit settings) are: // 2 Gs (00), 4 Gs (01), 8 Gs (10) 12 Gs (11). Here's a bit of an algorithm // to calculate Gs/(ADC tick) based on that 2-bit value: mRes = mScale == M_SCALE_2GS ? 2.0 / 32768.0 : (float) (mScale << 2) / 32768.0f; } void LSM9DS0::gWriteByte(uint8_t subAddress, uint8_t data) { // Whether we're using I2C or SPI, write a byte using the // gyro-specific I2C address or SPI CS pin. if (interfaceMode == I2C_MODE) I2CwriteByte(gAddress, subAddress, data); else if (interfaceMode == SPI_MODE) SPIwriteByte(gAddress, subAddress, data); } void LSM9DS0::xmWriteByte(uint8_t subAddress, uint8_t data) { // Whether we're using I2C or SPI, write a byte using the // accelerometer-specific I2C address or SPI CS pin. if (interfaceMode == I2C_MODE) return I2CwriteByte(xmAddress, subAddress, data); else if (interfaceMode == SPI_MODE) return SPIwriteByte(xmAddress, subAddress, data); } uint8_t LSM9DS0::gReadByte(uint8_t subAddress) { // Whether we're using I2C or SPI, read a byte using the // gyro-specific I2C address or SPI CS pin. if (interfaceMode == I2C_MODE) return I2CreadByte(gAddress, subAddress); else if (interfaceMode == SPI_MODE) return SPIreadByte(gAddress, subAddress); else return SPIreadByte(gAddress, subAddress); } void LSM9DS0::gReadBytes(uint8_t subAddress, uint8_t * dest, uint8_t count) { // Whether we're using I2C or SPI, read multiple bytes using the // gyro-specific I2C address or SPI CS pin. if (interfaceMode == I2C_MODE) I2CreadBytes(gAddress, subAddress, dest, count); else if (interfaceMode == SPI_MODE) SPIreadBytes(gAddress, subAddress, dest, count); } uint8_t LSM9DS0::xmReadByte(uint8_t subAddress) { // Whether we're using I2C or SPI, read a byte using the // accelerometer-specific I2C address or SPI CS pin. if (interfaceMode == I2C_MODE) return I2CreadByte(xmAddress, subAddress); else if (interfaceMode == SPI_MODE) return SPIreadByte(xmAddress, subAddress); else return SPIreadByte(xmAddress, subAddress); } void LSM9DS0::xmReadBytes(uint8_t subAddress, uint8_t * dest, uint8_t count) { // Whether we're using I2C or SPI, read multiple bytes using the // accelerometer-specific I2C address or SPI CS pin. if (interfaceMode == I2C_MODE) I2CreadBytes(xmAddress, subAddress, dest, count); else if (interfaceMode == SPI_MODE) SPIreadBytes(xmAddress, subAddress, dest, count); } void LSM9DS0::initSPI() { csG_ = 1; csXM_= 1; // Maximum SPI frequency is 10MHz: // spi_.frequency(1000000); spi_.format(8,0b11); } void LSM9DS0::SPIwriteByte(uint8_t csPin, uint8_t subAddress, uint8_t data) { // Initiate communication if(csPin == gAddress) csG_ = 0; else if(csPin == xmAddress) csXM_= 0; // If write, bit 0 (MSB) should be 0 // If single write, bit 1 should be 0 spi_.write(subAddress & 0x3F); // Send Address spi_.write(data); // Send data csG_ = 1; // Close communication csXM_= 1; } uint8_t LSM9DS0::SPIreadByte(uint8_t csPin, uint8_t subAddress) { uint8_t temp; // Use the multiple read function to read 1 byte. // Value is returned to `temp`. SPIreadBytes(csPin, subAddress, &temp, 1); return temp; } void LSM9DS0::SPIreadBytes(uint8_t csPin, uint8_t subAddress, uint8_t * dest, uint8_t count) { // Initiate communication if(csPin == gAddress) csG_ = 0; else if(csPin == xmAddress) csXM_= 0; // To indicate a read, set bit 0 (msb) to 1 // If we're reading multiple bytes, set bit 1 to 1 // The remaining six bytes are the address to be read if (count > 1) spi_.write(0xC0 | (subAddress & 0x3F)); else spi_.write(0x80 | (subAddress & 0x3F)); for (int i=0; i<count; i++) { dest[i] = spi_.write(0x00); // Read into destination array } csG_ = 1; // Close communication csXM_= 1; } void LSM9DS0::initI2C() { // Wire.begin(); // Initialize I2C library ; } // Wire.h read and write protocols void LSM9DS0::I2CwriteByte(uint8_t address, uint8_t subAddress, uint8_t data) { ; // Wire.beginTransmission(address); // Initialize the Tx buffer // Wire.write(subAddress); // Put slave register address in Tx buffer // Wire.write(data); // Put data in Tx buffer // Wire.endTransmission(); // Send the Tx buffer } uint8_t LSM9DS0::I2CreadByte(uint8_t address, uint8_t subAddress) { return 0; // uint8_t data; // `data` will store the register data // Wire.beginTransmission(address); // Initialize the Tx buffer // Wire.write(subAddress); // Put slave register address in Tx buffer // Wire.endTransmission(false); // Send the Tx buffer, but send a restart to keep connection alive // Wire.requestFrom(address, (uint8_t) 1); // Read one byte from slave register address // data = Wire.read(); // Fill Rx buffer with result // return data; // Return data read from slave register } void LSM9DS0::I2CreadBytes(uint8_t address, uint8_t subAddress, uint8_t * dest, uint8_t count) { ; // Wire.beginTransmission(address); // Initialize the Tx buffer // // Next send the register to be read. OR with 0x80 to indicate multi-read. // Wire.write(subAddress | 0x80); // Put slave register address in Tx buffer // Wire.endTransmission(false); // Send the Tx buffer, but send a restart to keep connection alive // uint8_t i = 0; // Wire.requestFrom(address, count); // Read bytes from slave register address // while (Wire.available()) // { // dest[i++] = Wire.read(); // Put read results in the Rx buffer // } }