IMU driver (this thing is a mess).

Dependents:   PM2_Libary PM2_Libary

Files at this revision

API Documentation at this revision

Comitter:
pmic
Date:
Wed Feb 23 07:16:58 2022 +0000
Commit message:
Included driver for LSM9DS1 IMU.

Changed in this revision

LSM9DS1_Registers.h Show annotated file Show diff for this revision Revisions of this file
LSM9DS1_Types.h Show annotated file Show diff for this revision Revisions of this file
LSM9DS1_i2c.cpp Show annotated file Show diff for this revision Revisions of this file
LSM9DS1_i2c.h Show annotated file Show diff for this revision Revisions of this file
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/LSM9DS1_Registers.h	Wed Feb 23 07:16:58 2022 +0000
@@ -0,0 +1,113 @@
+/******************************************************************************
+LSM9DS1_Registers.h
+SFE_LSM9DS1 Library - LSM9DS1 Register Map
+Jim Lindblom @ SparkFun Electronics
+Original Creation Date: April 21, 2015
+https://github.com/sparkfun/LSM9DS1_Breakout
+
+This file defines all registers internal to the gyro/accel and magnetometer
+devices in the LSM9DS1.
+
+Development environment specifics:
+    IDE: Arduino 1.6.0
+    Hardware Platform: Arduino Uno
+    LSM9DS1 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.
+******************************************************************************/
+
+#ifndef __LSM9DS1_Registers_H__
+#define __LSM9DS1_Registers_H__
+
+/////////////////////////////////////////
+// LSM9DS1 Accel/Gyro (XL/G) Registers //
+/////////////////////////////////////////
+#define ACT_THS             0x04
+#define ACT_DUR             0x05
+#define INT_GEN_CFG_XL      0x06
+#define INT_GEN_THS_X_XL    0x07
+#define INT_GEN_THS_Y_XL    0x08
+#define INT_GEN_THS_Z_XL    0x09
+#define INT_GEN_DUR_XL      0x0A
+#define REFERENCE_G         0x0B
+#define INT1_CTRL           0x0C
+#define INT2_CTRL           0x0D
+#define WHO_AM_I_XG         0x0F
+#define CTRL_REG1_G         0x10
+#define CTRL_REG2_G         0x11
+#define CTRL_REG3_G         0x12
+#define ORIENT_CFG_G        0x13
+#define INT_GEN_SRC_G       0x14
+#define OUT_TEMP_L          0x15
+#define OUT_TEMP_H          0x16
+#define STATUS_REG_0        0x17
+#define OUT_X_L_G           0x18
+#define OUT_X_H_G           0x19
+#define OUT_Y_L_G           0x1A
+#define OUT_Y_H_G           0x1B
+#define OUT_Z_L_G           0x1C
+#define OUT_Z_H_G           0x1D
+#define CTRL_REG4           0x1E
+#define CTRL_REG5_XL        0x1F
+#define CTRL_REG6_XL        0x20
+#define CTRL_REG7_XL        0x21
+#define CTRL_REG8           0x22
+#define CTRL_REG9           0x23
+#define CTRL_REG10          0x24
+#define INT_GEN_SRC_XL      0x26
+#define STATUS_REG_1        0x27
+#define OUT_X_L_XL          0x28
+#define OUT_X_H_XL          0x29
+#define OUT_Y_L_XL          0x2A
+#define OUT_Y_H_XL          0x2B
+#define OUT_Z_L_XL          0x2C
+#define OUT_Z_H_XL          0x2D
+#define FIFO_CTRL           0x2E
+#define FIFO_SRC            0x2F
+#define INT_GEN_CFG_G       0x30
+#define INT_GEN_THS_XH_G    0x31
+#define INT_GEN_THS_XL_G    0x32
+#define INT_GEN_THS_YH_G    0x33
+#define INT_GEN_THS_YL_G    0x34
+#define INT_GEN_THS_ZH_G    0x35
+#define INT_GEN_THS_ZL_G    0x36
+#define INT_GEN_DUR_G       0x37
+
+///////////////////////////////
+// LSM9DS1 Magneto Registers //
+///////////////////////////////
+#define OFFSET_X_REG_L_M    0x05
+#define OFFSET_X_REG_H_M    0x06
+#define OFFSET_Y_REG_L_M    0x07
+#define OFFSET_Y_REG_H_M    0x08
+#define OFFSET_Z_REG_L_M    0x09
+#define OFFSET_Z_REG_H_M    0x0A
+#define WHO_AM_I_M          0x0F
+#define CTRL_REG1_M         0x20
+#define CTRL_REG2_M         0x21
+#define CTRL_REG3_M         0x22
+#define CTRL_REG4_M         0x23
+#define CTRL_REG5_M         0x24
+#define STATUS_REG_M        0x27
+#define OUT_X_L_M           0x28
+#define OUT_X_H_M           0x29
+#define OUT_Y_L_M           0x2A
+#define OUT_Y_H_M           0x2B
+#define OUT_Z_L_M           0x2C
+#define OUT_Z_H_M           0x2D
+#define INT_CFG_M           0x30
+#define INT_SRC_M           0x30
+#define INT_THS_L_M         0x32
+#define INT_THS_H_M         0x33
+
+////////////////////////////////
+// LSM9DS1 WHO_AM_I Responses //
+////////////////////////////////
+#define WHO_AM_I_AG_RSP     0x68
+#define WHO_AM_I_M_RSP      0x3D
+
+#endif
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/LSM9DS1_Types.h	Wed Feb 23 07:16:58 2022 +0000
@@ -0,0 +1,251 @@
+/******************************************************************************
+LSM9DS1_Types.h
+SFE_LSM9DS1 Library - LSM9DS1 Types and Enumerations
+Jim Lindblom @ SparkFun Electronics
+Original Creation Date: April 21, 2015
+https://github.com/sparkfun/LSM9DS1_Breakout
+
+This file defines all types and enumerations used by the LSM9DS1 class.
+
+Development environment specifics:
+    IDE: Arduino 1.6.0
+    Hardware Platform: Arduino Uno
+    LSM9DS1 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.
+******************************************************************************/
+
+#ifndef __LSM9DS1_Types_H__
+#define __LSM9DS1_Types_H__
+
+#include "LSM9DS1_Registers.h"
+
+// The LSM9DS1 functions over both I2C or SPI. This library supports both.
+// But the interface mode used must be sent to the LSM9DS1 constructor. Use
+// one of these two as the first parameter of the constructor.
+enum interface_mode
+{
+    IMU_MODE_SPI,
+    IMU_MODE_I2C,
+};
+
+// accel_scale defines all possible FSR's of the accelerometer:
+enum accel_scale
+{
+    A_SCALE_2G, // 00:  2g
+    A_SCALE_16G,// 01:  16g
+    A_SCALE_4G, // 10:  4g
+    A_SCALE_8G  // 11:  8g
+};
+
+// gyro_scale defines the possible full-scale ranges of the gyroscope:
+enum gyro_scale
+{
+    G_SCALE_245DPS,     // 00:  245 degrees per second
+    G_SCALE_500DPS,     // 01:  500 dps
+    G_SCALE_2000DPS,    // 11:  2000 dps
+};
+
+// mag_scale defines all possible FSR's of the magnetometer:
+enum mag_scale
+{
+    M_SCALE_4GS,    // 00:  4Gs
+    M_SCALE_8GS,    // 01:  8Gs
+    M_SCALE_12GS,   // 10:  12Gs
+    M_SCALE_16GS,   // 11:  16Gs
+};
+
+// gyro_odr defines all possible data rate/bandwidth combos of the gyro:
+enum gyro_odr
+{
+    //! TODO 
+    G_ODR_PD,   // Power down (0)
+    G_ODR_149,  // 14.9 Hz (1)
+    G_ODR_595,  // 59.5 Hz (2)
+    G_ODR_119,  // 119 Hz (3)
+    G_ODR_238,  // 238 Hz (4)
+    G_ODR_476,  // 476 Hz (5)
+    G_ODR_952   // 952 Hz (6)
+};
+// accel_oder defines all possible output data rates of the accelerometer:
+enum accel_odr
+{
+    XL_POWER_DOWN,  // Power-down mode (0x0)
+    XL_ODR_10,      // 10 Hz (0x1)
+    XL_ODR_50,      // 50 Hz (0x02)
+    XL_ODR_119,     // 119 Hz (0x3)
+    XL_ODR_238,     // 238 Hz (0x4)
+    XL_ODR_476,     // 476 Hz (0x5)
+    XL_ODR_952      // 952 Hz (0x6)
+};
+
+// accel_abw defines all possible anti-aliasing filter rates of the accelerometer:
+enum accel_abw
+{
+    A_ABW_408,      // 408 Hz (0x0)
+    A_ABW_211,      // 211 Hz (0x1)
+    A_ABW_105,      // 105 Hz (0x2)
+    A_ABW_50,       //  50 Hz (0x3)
+};
+
+
+// mag_odr defines all possible output data rates of the magnetometer:
+enum mag_odr
+{
+    M_ODR_0625, // 0.625 Hz (0)
+    M_ODR_125,  // 1.25 Hz (1)
+    M_ODR_250,  // 2.5 Hz (2)
+    M_ODR_5,    // 5 Hz (3)
+    M_ODR_10,   // 10 Hz (4)
+    M_ODR_20,   // 20 Hz (5)
+    M_ODR_40,   // 40 Hz (6)
+    M_ODR_80    // 80 Hz (7)
+};
+
+enum interrupt_select
+{
+    XG_INT1 = INT1_CTRL,
+    XG_INT2 = INT2_CTRL
+};
+
+enum interrupt_generators
+{
+    INT_DRDY_XL = (1<<0),    // Accelerometer data ready (INT1 & INT2)
+    INT_DRDY_G = (1<<1),     // Gyroscope data ready (INT1 & INT2)
+    INT1_BOOT = (1<<2),  // Boot status (INT1)
+    INT2_DRDY_TEMP = (1<<2),// Temp data ready (INT2)
+    INT_FTH = (1<<3),        // FIFO threshold interrupt (INT1 & INT2)
+    INT_OVR = (1<<4),        // Overrun interrupt (INT1 & INT2)
+    INT_FSS5 = (1<<5),       // FSS5 interrupt (INT1 & INT2)
+    INT_IG_XL = (1<<6),  // Accel interrupt generator (INT1)
+    INT1_IG_G = (1<<7),  // Gyro interrupt enable (INT1)
+    INT2_INACT = (1<<7),     // Inactivity interrupt output (INT2)
+};  
+
+enum accel_interrupt_generator
+{
+    XLIE_XL = (1<<0),
+    XHIE_XL = (1<<1),
+    YLIE_XL = (1<<2),
+    YHIE_XL = (1<<3),
+    ZLIE_XL = (1<<4),
+    ZHIE_XL = (1<<5),
+    GEN_6D = (1<<6)
+};
+
+enum gyro_interrupt_generator
+{
+    XLIE_G = (1<<0),
+    XHIE_G = (1<<1),
+    YLIE_G = (1<<2),
+    YHIE_G = (1<<3),
+    ZLIE_G = (1<<4),
+    ZHIE_G = (1<<5)
+};
+
+enum mag_interrupt_generator
+{
+    ZIEN = (1<<5),
+    YIEN = (1<<6),
+    XIEN = (1<<7)
+};
+
+enum h_lactive
+{
+    INT_ACTIVE_HIGH,
+    INT_ACTIVE_LOW
+};
+
+enum pp_od
+{
+    INT_PUSH_PULL,
+    INT_OPEN_DRAIN
+};
+
+enum fifoMode_type
+{
+    FIFO_OFF = 0,
+    FIFO_THS = 1,
+    FIFO_CONT_TRIGGER = 3,
+    FIFO_OFF_TRIGGER = 4,
+    FIFO_CONT = 5
+};
+
+struct gyroSettings
+{
+    // Gyroscope settings:
+    uint8_t enabled;
+    uint16_t scale; // Changed this to 16-bit
+    uint8_t sampleRate;
+    // New gyro stuff:
+    uint8_t bandwidth;
+    uint8_t lowPowerEnable;
+    uint8_t HPFEnable;
+    uint8_t HPFCutoff;
+    uint8_t flipX;
+    uint8_t flipY;
+    uint8_t flipZ;
+    uint8_t orientation;
+    uint8_t enableX;
+    uint8_t enableY;
+    uint8_t enableZ;
+    uint8_t latchInterrupt;
+};
+
+struct deviceSettings
+{
+    uint8_t commInterface; // Can be I2C, SPI 4-wire or SPI 3-wire
+    uint8_t agAddress;  // I2C address or SPI CS pin
+    uint8_t mAddress;   // I2C address or SPI CS pin
+};
+
+struct accelSettings
+{
+    // Accelerometer settings:
+    uint8_t enabled;
+    uint8_t scale;
+    uint8_t sampleRate;
+    // New accel stuff:
+    uint8_t enableX;
+    uint8_t enableY;
+    uint8_t enableZ;
+    int8_t  bandwidth;
+    uint8_t highResEnable;
+    uint8_t highResBandwidth;
+};
+
+struct magSettings
+{
+    // Magnetometer settings:
+    uint8_t enabled;
+    uint8_t scale;
+    uint8_t sampleRate;
+    // New mag stuff:
+    uint8_t tempCompensationEnable;
+    uint8_t XYPerformance;
+    uint8_t ZPerformance;
+    uint8_t lowPowerEnable;
+    uint8_t operatingMode;
+};
+
+struct temperatureSettings
+{
+    // Temperature settings
+    uint8_t enabled;
+};
+
+struct IMUSettings
+{
+    deviceSettings device;
+    
+    gyroSettings gyro;
+    accelSettings accel;
+    magSettings mag;
+    
+    temperatureSettings temp;
+};
+
+#endif
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/LSM9DS1_i2c.cpp	Wed Feb 23 07:16:58 2022 +0000
@@ -0,0 +1,1246 @@
+/******************************************************************************
+SFE_LSM9DS1.cpp
+SFE_LSM9DS1 Library Source File
+Jim Lindblom @ SparkFun Electronics
+Original Creation Date: February 27, 2015
+https://github.com/sparkfun/LSM9DS1_Breakout
+
+This file implements all functions of the LSM9DS1 class. Functions here range
+from higher level stuff, like reading/writing LSM9DS1 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 1.6
+    Hardware Platform: Arduino Uno
+    LSM9DS1 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.
+
+Modified: Nicolas Borla, 20.01.2019
+******************************************************************************/
+
+#include "LSM9DS1_i2c.h"
+#include "LSM9DS1_Registers.h"
+#include "LSM9DS1_Types.h"
+//#include <Wire.h> // Wire library is used for I2C
+//#include <SPI.h>  // SPI library is used for...SPI.
+
+//#if defined(ARDUINO) && ARDUINO >= 100
+//  #include "Arduino.h"
+//#else
+//  #include "WProgram.h"
+//#endif
+
+#define LSM9DS1_COMMUNICATION_TIMEOUT 1000
+
+float magSensitivity[4] = {0.00014, 0.00029, 0.00043, 0.00058};
+//extern Serial pc;
+
+LSM9DS1::LSM9DS1(PinName sda, PinName scl, uint8_t xgAddr, uint8_t mAddr)
+    :i2c(sda, scl)
+{
+    init(IMU_MODE_I2C, xgAddr, mAddr); // dont know about 0xD6 or 0x3B
+    begin();
+}
+
+LSM9DS1::LSM9DS1(PinName sda, PinName scl)
+    :i2c(sda, scl)
+{
+    init(IMU_MODE_I2C, 0xD6, 0x3C); // dont know about 0xD6 or 0x3B
+    begin();
+}
+
+/*
+LSM9DS1::LSM9DS1()
+{
+    init(IMU_MODE_I2C, LSM9DS1_AG_ADDR(1), LSM9DS1_M_ADDR(1));
+}
+
+LSM9DS1::LSM9DS1(interface_mode interface, uint8_t xgAddr, uint8_t mAddr)
+{
+    init(interface, xgAddr, mAddr);
+}
+*/
+
+void LSM9DS1::init(interface_mode interface, uint8_t xgAddr, uint8_t mAddr)
+{
+    settings.device.commInterface = interface;
+    settings.device.agAddress = xgAddr;
+    settings.device.mAddress = mAddr;
+
+    settings.gyro.enabled = true;
+    settings.gyro.enableX = true;
+    settings.gyro.enableY = true;
+    settings.gyro.enableZ = true;
+    // gyro scale can be 245, 500, or 2000 dps (degree per second)
+    settings.gyro.scale = 500;
+    // gyro sample rate: value between 1-6 in Hz
+    // 1 = 14.9    4 = 238
+    // 2 = 59.5    5 = 476
+    // 3 = 119     6 = 952
+    settings.gyro.sampleRate = 5;
+    // gyro cutoff frequency: value between 0-3
+    // Actual value of cutoff frequency depends
+    // on sample rate.
+    // @476 Hz: 0 ->  21 Hz only if LPF2 is enabled, to do so you need to set xgWriteByte(CTRL_REG2_G, 0x02) to enable LPF 2, pmic 11.09.2019 
+    //          1 ->  28 Hz
+    //          2 ->  57 Hz
+    //          3 -> 100 Hz
+    settings.gyro.bandwidth = 1; 
+    settings.gyro.lowPowerEnable = false;
+    settings.gyro.HPFEnable = false;
+    // Gyro HPF cutoff frequency: value between 0-9
+    // Actual value depends on sample rate. Only applies
+    // if gyroHPFEnable is true.
+    settings.gyro.HPFCutoff = 0;
+    settings.gyro.flipX = false;
+    settings.gyro.flipY = false;
+    settings.gyro.flipZ = false;
+    settings.gyro.orientation = 0;
+    settings.gyro.latchInterrupt = true;
+
+    settings.accel.enabled = true;
+    settings.accel.enableX = true;
+    settings.accel.enableY = true;
+    settings.accel.enableZ = true;
+    // accel scale can be 2, 4, 8, or 16
+    settings.accel.scale = 2;
+    // accel sample rate can be 1-6
+    // 1 = 10 Hz    4 = 238 Hz
+    // 2 = 50 Hz    5 = 476 Hz
+    // 3 = 119 Hz   6 = 952 Hz
+    settings.accel.sampleRate = 5;
+    // Accel cutoff freqeuncy can be any value between -1 - 3. 
+    // -1 = bandwidth determined by sample rate
+    // 0 = 408 Hz   2 = 105 Hz
+    // 1 = 211 Hz   3 = 50 Hz
+    settings.accel.bandwidth = 3;
+    settings.accel.highResEnable = false;
+    // accelHighResBandwidth can be any value between 0-3
+    // LP cutoff is set to a factor of sample rate
+    // 0 = ODR/50    2 = ODR/9
+    // 1 = ODR/100   3 = ODR/400
+    settings.accel.highResBandwidth = 0;
+
+    settings.mag.enabled = true;
+    // mag scale can be 4, 8, 12, or 16
+    settings.mag.scale = 4;
+    // mag data rate can be 0-7
+    // 0 = 0.625 Hz  4 = 10 Hz
+    // 1 = 1.25 Hz   5 = 20 Hz
+    // 2 = 2.5 Hz    6 = 40 Hz
+    // 3 = 5 Hz      7 = 80 Hz
+    settings.mag.sampleRate = 7;
+    settings.mag.tempCompensationEnable = true;
+    // magPerformance can be any value between 0-3
+    // 0 = Low power mode      2 = high performance
+    // 1 = medium performance  3 = ultra-high performance
+    settings.mag.XYPerformance = 2;
+    settings.mag.ZPerformance = 2;
+    settings.mag.lowPowerEnable = false;
+    // magOperatingMode can be 0-2
+    // 0 = continuous conversion
+    // 1 = single-conversion
+    // 2 = power down
+    settings.mag.operatingMode = 0;
+
+    settings.temp.enabled = true;
+    for (int i=0; i<3; i++)
+    {
+        gBias[i] = 0;
+        aBias[i] = 0;
+        mBias[i] = 0;
+        gBiasRaw[i] = 0;
+        aBiasRaw[i] = 0;
+        mBiasRaw[i] = 0;
+    }
+    _autoCalc = false;
+}
+
+
+uint16_t LSM9DS1::begin()
+{
+    //! Todo: don't use _xgAddress or _mAddress, duplicating memory
+    _xgAddress = settings.device.agAddress;
+    _mAddress = settings.device.mAddress;
+    
+    constrainScales();
+    // 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 (settings.device.commInterface == IMU_MODE_I2C)  // If we're using I2C
+        initI2C();  // Initialize I2C
+    else if (settings.device.commInterface == IMU_MODE_SPI)     // 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 mTest = mReadByte(WHO_AM_I_M);      // Read the gyro WHO_AM_I
+    uint8_t xgTest = xgReadByte(WHO_AM_I_XG);   // Read the accel/mag WHO_AM_I
+    printf("%x, %x, %x, %x\n\r", mTest, xgTest, _xgAddress, _mAddress);
+    uint16_t whoAmICombined = (xgTest << 8) | mTest;
+    
+    if (whoAmICombined != ((WHO_AM_I_AG_RSP << 8) | WHO_AM_I_M_RSP))
+        return 0;
+    
+    // Gyro initialization stuff:
+    initGyro(); // This will "turn on" the gyro. Setting up interrupts, etc.
+    
+    // Accelerometer initialization stuff:
+    initAccel(); // "Turn on" all axes of the accel. Set up interrupts, etc.
+    
+    // Magnetometer initialization stuff:
+    initMag(); // "Turn on" all axes of the mag. Set up interrupts, etc.
+
+    // Once everything is initialized, return the WHO_AM_I registers we read:
+    return whoAmICombined;
+}
+
+float LSM9DS1::readGyroX(){return gyroX;}
+float LSM9DS1::readGyroY(){return gyroY;}
+float LSM9DS1::readGyroZ(){return gyroZ;}
+float LSM9DS1::readAccX(){return accX;}
+float LSM9DS1::readAccY(){return accY;}
+float LSM9DS1::readAccZ(){return accZ;}
+float LSM9DS1::readMagX(){return magX;}
+float LSM9DS1::readMagY(){return magY;}
+float LSM9DS1::readMagZ(){return magZ;}
+
+void LSM9DS1::initGyro()
+{
+    uint8_t tempRegValue = 0;
+    
+    // CTRL_REG1_G (Default value: 0x00)
+    // [ODR_G2][ODR_G1][ODR_G0][FS_G1][FS_G0][0][BW_G1][BW_G0]
+    // ODR_G[2:0] - Output data rate selection
+    // FS_G[1:0] - Gyroscope full-scale selection
+    // BW_G[1:0] - Gyroscope bandwidth selection
+    
+    // To disable gyro, set sample rate bits to 0. We'll only set sample
+    // rate if the gyro is enabled.
+    if (settings.gyro.enabled)
+    {
+        tempRegValue = (settings.gyro.sampleRate & 0x07) << 5;
+    }
+    switch (settings.gyro.scale)
+    {
+        case 500:
+            tempRegValue |= (0x1 << 3);
+            break;
+        case 2000:
+            tempRegValue |= (0x3 << 3);
+            break;
+        // Otherwise we'll set it to 245 dps (0x0 << 4)
+    }
+    tempRegValue |= (settings.gyro.bandwidth & 0x3);
+    xgWriteByte(CTRL_REG1_G, tempRegValue);
+    
+    // CTRL_REG2_G (Default value: 0x00)
+    // [0][0][0][0][INT_SEL1][INT_SEL0][OUT_SEL1][OUT_SEL0]
+    // INT_SEL[1:0] - INT selection configuration
+    // OUT_SEL[1:0] - Out selection configuration
+    xgWriteByte(CTRL_REG2_G, 0x02); // use xgWriteByte(CTRL_REG2_G, 0x00); to disable LPF 2, pmic 11.09.2019 
+    
+    // CTRL_REG3_G (Default value: 0x00)
+    // [LP_mode][HP_EN][0][0][HPCF3_G][HPCF2_G][HPCF1_G][HPCF0_G]
+    // LP_mode - Low-power mode enable (0: disabled, 1: enabled)
+    // HP_EN - HPF enable (0:disabled, 1: enabled)
+    // HPCF_G[3:0] - HPF cutoff frequency
+    tempRegValue = settings.gyro.lowPowerEnable ? (1<<7) : 0;
+    if (settings.gyro.HPFEnable)
+    {
+        tempRegValue |= (1<<6) | (settings.gyro.HPFCutoff & 0x0F);
+    }
+    xgWriteByte(CTRL_REG3_G, tempRegValue);
+    
+    // CTRL_REG4 (Default value: 0x38)
+    // [0][0][Zen_G][Yen_G][Xen_G][0][LIR_XL1][4D_XL1]
+    // Zen_G - Z-axis output enable (0:disable, 1:enable)
+    // Yen_G - Y-axis output enable (0:disable, 1:enable)
+    // Xen_G - X-axis output enable (0:disable, 1:enable)
+    // LIR_XL1 - Latched interrupt (0:not latched, 1:latched)
+    // 4D_XL1 - 4D option on interrupt (0:6D used, 1:4D used)
+    tempRegValue = 0;
+    if (settings.gyro.enableZ) tempRegValue |= (1<<5);
+    if (settings.gyro.enableY) tempRegValue |= (1<<4);
+    if (settings.gyro.enableX) tempRegValue |= (1<<3);
+    if (settings.gyro.latchInterrupt) tempRegValue |= (1<<1);
+    xgWriteByte(CTRL_REG4, tempRegValue);
+    
+    // ORIENT_CFG_G (Default value: 0x00)
+    // [0][0][SignX_G][SignY_G][SignZ_G][Orient_2][Orient_1][Orient_0]
+    // SignX_G - Pitch axis (X) angular rate sign (0: positive, 1: negative)
+    // Orient [2:0] - Directional user orientation selection
+    tempRegValue = 0;
+    if (settings.gyro.flipX) tempRegValue |= (1<<5);
+    if (settings.gyro.flipY) tempRegValue |= (1<<4);
+    if (settings.gyro.flipZ) tempRegValue |= (1<<3);
+    xgWriteByte(ORIENT_CFG_G, tempRegValue);
+}
+
+void LSM9DS1::initAccel()
+{
+    uint8_t tempRegValue = 0;
+    
+    //  CTRL_REG5_XL (0x1F) (Default value: 0x38)
+    //  [DEC_1][DEC_0][Zen_XL][Yen_XL][Zen_XL][0][0][0]
+    //  DEC[0:1] - Decimation of accel data on OUT REG and FIFO.
+    //      00: None, 01: 2 samples, 10: 4 samples 11: 8 samples
+    //  Zen_XL - Z-axis output enabled
+    //  Yen_XL - Y-axis output enabled
+    //  Xen_XL - X-axis output enabled
+    if (settings.accel.enableZ) tempRegValue |= (1<<5);
+    if (settings.accel.enableY) tempRegValue |= (1<<4);
+    if (settings.accel.enableX) tempRegValue |= (1<<3);
+    
+    xgWriteByte(CTRL_REG5_XL, tempRegValue);
+    
+    // CTRL_REG6_XL (0x20) (Default value: 0x00)
+    // [ODR_XL2][ODR_XL1][ODR_XL0][FS1_XL][FS0_XL][BW_SCAL_ODR][BW_XL1][BW_XL0]
+    // ODR_XL[2:0] - Output data rate & power mode selection
+    // FS_XL[1:0] - Full-scale selection
+    // BW_SCAL_ODR - Bandwidth selection
+    // BW_XL[1:0] - Anti-aliasing filter bandwidth selection
+    tempRegValue = 0;
+    // To disable the accel, set the sampleRate bits to 0.
+    if (settings.accel.enabled)
+    {
+        tempRegValue |= (settings.accel.sampleRate & 0x07) << 5;
+    }
+    switch (settings.accel.scale)
+    {
+        case 4:
+            tempRegValue |= (0x2 << 3);
+            break;
+        case 8:
+            tempRegValue |= (0x3 << 3);
+            break;
+        case 16:
+            tempRegValue |= (0x1 << 3);
+            break;
+        // Otherwise it'll be set to 2g (0x0 << 3)
+    }
+    if (settings.accel.bandwidth >= 0)
+    {
+        tempRegValue |= (1<<2); // Set BW_SCAL_ODR
+        tempRegValue |= (settings.accel.bandwidth & 0x03);
+    }
+    xgWriteByte(CTRL_REG6_XL, tempRegValue);
+    
+    // CTRL_REG7_XL (0x21) (Default value: 0x00)
+    // [HR][DCF1][DCF0][0][0][FDS][0][HPIS1]
+    // HR - High resolution mode (0: disable, 1: enable)
+    // DCF[1:0] - Digital filter cutoff frequency
+    // FDS - Filtered data selection
+    // HPIS1 - HPF enabled for interrupt function
+    tempRegValue = 0;
+    if (settings.accel.highResEnable)
+    {
+        tempRegValue |= (1<<7); // Set HR bit
+        tempRegValue |= (settings.accel.highResBandwidth & 0x3) << 5;
+    }
+    xgWriteByte(CTRL_REG7_XL, tempRegValue);
+}
+
+// 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 LSM9DS1::calibrate(bool autoCalc)
+{  
+    uint8_t data[6] = {0, 0, 0, 0, 0, 0};
+    uint8_t samples = 0;
+    int ii;
+    int32_t aBiasRawTemp[3] = {0, 0, 0};
+    int32_t gBiasRawTemp[3] = {0, 0, 0};
+    
+    // Turn on FIFO and set threshold to 32 samples
+    enableFIFO(true);
+    setFIFO(FIFO_THS, 0x1F);
+    while (samples < 0x7F)
+    {
+        samples = (xgReadByte(FIFO_SRC) & 0x3F); // Read number of stored samples
+    }
+    for(ii = 0; ii < samples ; ii++) 
+    {   // Read the gyro data stored in the FIFO
+        updateGyro();
+        gBiasRawTemp[0] += gx;
+        gBiasRawTemp[1] += gy;
+        gBiasRawTemp[2] += gz;
+        updateAcc();
+        aBiasRawTemp[0] += ax;
+        aBiasRawTemp[1] += ay;
+        aBiasRawTemp[2] += az - (int32_t)(1.0f/aRes); // Assumes sensor facing up!
+    }  
+    for (ii = 0; ii < 3; ii++)
+    {
+        gBiasRaw[ii] = gBiasRawTemp[ii] / samples;
+        gBias[ii] = calcGyro(gBiasRaw[ii]);
+        aBiasRaw[ii] = aBiasRawTemp[ii] / samples;
+        aBias[ii] = calcAccel(aBiasRaw[ii]);
+    }
+    
+    enableFIFO(false);
+    setFIFO(FIFO_OFF, 0x00);
+    
+    if (autoCalc) _autoCalc = true;
+}
+
+void LSM9DS1::calibrateMag(bool loadIn)
+{
+    int i, j;
+    int16_t magMin[3] = {0, 0, 0};
+    int16_t magMax[3] = {0, 0, 0}; // The road warrior
+    
+    for (i=0; i<128; i++)
+    {
+        while (!magAvailable());
+        updateMag();
+        int16_t magTemp[3] = {0, 0, 0};
+        magTemp[0] = mx;        
+        magTemp[1] = my;
+        magTemp[2] = mz;
+        for (j = 0; j < 3; j++)
+        {
+            if (magTemp[j] > magMax[j]) magMax[j] = magTemp[j];
+            if (magTemp[j] < magMin[j]) magMin[j] = magTemp[j];
+        }
+    }
+    for (j = 0; j < 3; j++)
+    {
+        mBiasRaw[j] = (magMax[j] + magMin[j]) / 2;
+        mBias[j] = calcMag(mBiasRaw[j]);
+        if (loadIn)
+            magOffset(j, mBiasRaw[j]);
+    }
+    
+}
+void LSM9DS1::magOffset(uint8_t axis, int16_t offset)
+{
+    if (axis > 2)
+        return;
+    uint8_t msb, lsb;
+    msb = (offset & 0xFF00) >> 8;
+    lsb = offset & 0x00FF;
+    mWriteByte(OFFSET_X_REG_L_M + (2 * axis), lsb);
+    mWriteByte(OFFSET_X_REG_H_M + (2 * axis), msb);
+}
+
+void LSM9DS1::initMag()
+{
+    uint8_t tempRegValue = 0;
+    
+    // CTRL_REG1_M (Default value: 0x10)
+    // [TEMP_COMP][OM1][OM0][DO2][DO1][DO0][0][ST]
+    // TEMP_COMP - Temperature compensation
+    // OM[1:0] - X & Y axes op mode selection
+    //  00:low-power, 01:medium performance
+    //  10: high performance, 11:ultra-high performance
+    // DO[2:0] - Output data rate selection
+    // ST - Self-test enable
+    if (settings.mag.tempCompensationEnable) tempRegValue |= (1<<7);
+    tempRegValue |= (settings.mag.XYPerformance & 0x3) << 5;
+    tempRegValue |= (settings.mag.sampleRate & 0x7) << 2;
+    // mWriteByte(CTRL_REG1_M, tempRegValue); 
+    // pmic 21.09.2019, settings now static
+    // use 0xC2 for temperature compensation on, Fast ODR -> 300 Hz undocumented mode high performance
+    // use 0x42 for temperature compensation off, Fast ODR -> 300 Hz undocumented mode high performance
+    // use 0xE2 for temperature compensation on, Fast ODR -> 155 Hz undocumented mode ultra high performance
+    // use 0x62 for temperature compensation off, Fast ODR -> 155 Hz undocumented mode ultra high performance
+    // use 0xA2 for temperature compensation on, Fast ODR -> 155 Hz undocumented mode medium performance
+    // use 0x22 for temperature compensation off, Fast ODR -> 155 Hz undocumented mode medium performance
+    mWriteByte(CTRL_REG1_M, 0xC2); 
+    
+    // CTRL_REG2_M (Default value 0x00)
+    // [0][FS1][FS0][0][REBOOT][SOFT_RST][0][0]
+    // FS[1:0] - Full-scale configuration
+    // REBOOT - Reboot memory content (0:normal, 1:reboot)
+    // SOFT_RST - Reset config and user registers (0:default, 1:reset)
+    tempRegValue = 0;
+    switch (settings.mag.scale)
+    {
+    case 8:
+        tempRegValue |= (0x1 << 5);
+        break;
+    case 12:
+        tempRegValue |= (0x2 << 5);
+        break;
+    case 16:
+        tempRegValue |= (0x3 << 5);
+        break;
+    // Otherwise we'll default to 4 gauss (00)
+    }
+    mWriteByte(CTRL_REG2_M, tempRegValue); // +/-4Gauss
+    
+    // CTRL_REG3_M (Default value: 0x03)
+    // [I2C_DISABLE][0][LP][0][0][SIM][MD1][MD0]
+    // I2C_DISABLE - Disable I2C interace (0:enable, 1:disable)
+    // LP - Low-power mode cofiguration (1:enable)
+    // SIM - SPI mode selection (0:write-only, 1:read/write enable)
+    // MD[1:0] - Operating mode
+    //  00:continuous conversion, 01:single-conversion,
+    //  10,11: Power-down
+    tempRegValue = 0;
+    if (settings.mag.lowPowerEnable) tempRegValue |= (1<<5);
+    tempRegValue |= (settings.mag.operatingMode & 0x3);
+    mWriteByte(CTRL_REG3_M, tempRegValue); // Continuous conversion mode
+    
+    // CTRL_REG4_M (Default value: 0x00)
+    // [0][0][0][0][OMZ1][OMZ0][BLE][0]
+    // OMZ[1:0] - Z-axis operative mode selection
+    //  00:low-power mode, 01:medium performance
+    //  10:high performance, 11:ultra-high performance
+    // BLE - Big/little endian data
+    tempRegValue = 0;
+    tempRegValue = (settings.mag.ZPerformance & 0x3) << 2;
+    mWriteByte(CTRL_REG4_M, tempRegValue);
+    
+    // CTRL_REG5_M (Default value: 0x00)
+    // [0][BDU][0][0][0][0][0][0]
+    // BDU - Block data update for magnetic data
+    //  0:continuous, 1:not updated until MSB/LSB are read
+    tempRegValue = 0;
+    mWriteByte(CTRL_REG5_M, tempRegValue);
+}
+
+uint8_t LSM9DS1::accelAvailable()
+{
+    uint8_t status = xgReadByte(STATUS_REG_1);
+    
+    return (status & (1<<0));
+}
+
+uint8_t LSM9DS1::gyroAvailable()
+{
+    uint8_t status = xgReadByte(STATUS_REG_1);
+    
+    return ((status & (1<<1)) >> 1);
+}
+
+uint8_t LSM9DS1::tempAvailable()
+{
+    uint8_t status = xgReadByte(STATUS_REG_1);
+    
+    return ((status & (1<<2)) >> 2);
+}
+
+uint8_t LSM9DS1::magAvailable(lsm9ds1_axis axis)
+{
+    uint8_t status;
+    status = mReadByte(STATUS_REG_M);
+    
+    return ((status & (1<<axis)) >> axis);
+}
+
+void LSM9DS1::updateAcc()
+{
+    uint8_t temp[6]; // We'll read six bytes from the accelerometer into temp   
+    xgReadBytes(OUT_X_L_XL, temp, 6); // Read 6 bytes, beginning at OUT_X_L_XL
+    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
+    if (_autoCalc)
+    {
+        ax -= aBiasRaw[X_AXIS];
+        ay -= aBiasRaw[Y_AXIS];
+        az -= aBiasRaw[Z_AXIS];
+    }
+    accX = static_cast<float>(ax)/32768.0f*2.0f*9.81f;
+    accY = static_cast<float>(ay)/32768.0f*2.0f*9.81f;
+    accZ = static_cast<float>(az)/32768.0f*2.0f*9.81f;
+}
+
+int16_t LSM9DS1::updateAcc(lsm9ds1_axis axis)
+{
+    uint8_t temp[2];
+    int16_t value;
+    xgReadBytes(OUT_X_L_XL + (2 * axis), temp, 2);
+    value = (temp[1] << 8) | temp[0];
+    
+    if (_autoCalc)
+        value -= aBiasRaw[axis];
+    
+    return value;
+}
+
+void LSM9DS1::updateMag()
+{
+    uint8_t temp[6]; // We'll read six bytes from the mag into temp 
+    mReadBytes(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
+    
+    magX = static_cast<float>(mx)/32768.0f*4.0f;
+    magY = static_cast<float>(my)/32768.0f*4.0f;
+    magZ = static_cast<float>(mz)/32768.0f*4.0f;
+}
+
+int16_t LSM9DS1::updateMag(lsm9ds1_axis axis)
+{
+    uint8_t temp[2];
+    mReadBytes(OUT_X_L_M + (2 * axis), temp, 2);
+    return (temp[1] << 8) | temp[0];
+}
+
+void LSM9DS1::readTemp()
+{
+    uint8_t temp[2]; // We'll read two bytes from the temperature sensor into temp  
+    xgReadBytes(OUT_TEMP_L, temp, 2); // Read 2 bytes, beginning at OUT_TEMP_L
+    temperature = ((int16_t)temp[1] << 8) | temp[0];
+}
+
+void LSM9DS1::updateGyro()
+{
+    uint8_t temp[6]; // We'll read six bytes from the gyro into temp
+    xgReadBytes(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
+    if (_autoCalc)
+    {
+        gx -= gBiasRaw[X_AXIS];
+        gy -= gBiasRaw[Y_AXIS];
+        gz -= gBiasRaw[Z_AXIS];
+    }
+    gyroX = static_cast<float>(gx)/32768.0f*(float)settings.gyro.scale*3.14159265358979323846f/180.0f * 1.17f; // measured correction 1.17, pmic 04.09.2019
+    gyroY = static_cast<float>(gy)/32768.0f*(float)settings.gyro.scale*3.14159265358979323846f/180.0f * 1.17f;
+    gyroZ = static_cast<float>(gz)/32768.0f*(float)settings.gyro.scale*3.14159265358979323846f/180.0f * 1.17f;
+}
+
+int16_t LSM9DS1::updateGyro(lsm9ds1_axis axis)
+{
+    uint8_t temp[2];
+    int16_t value;
+    
+    xgReadBytes(OUT_X_L_G + (2 * axis), temp, 2);
+    
+    value = (temp[1] << 8) | temp[0];
+    
+    if (_autoCalc)
+        value -= gBiasRaw[axis];
+    
+    return value;
+}
+
+float LSM9DS1::calcGyro(int16_t gyro)
+{
+    // Return the gyro raw reading times our pre-calculated DPS / (ADC tick):
+    return gRes * gyro; 
+}
+
+float LSM9DS1::calcAccel(int16_t accel)
+{
+    // Return the accel raw reading times our pre-calculated g's / (ADC tick):
+    return aRes * accel;
+}
+
+float LSM9DS1::calcMag(int16_t mag)
+{
+    // Return the mag raw reading times our pre-calculated Gs / (ADC tick):
+    return mRes * mag;
+}
+
+void LSM9DS1::setGyroScale(uint16_t gScl)
+{
+    // Read current value of CTRL_REG1_G:
+    uint8_t ctrl1RegValue = xgReadByte(CTRL_REG1_G);
+    // Mask out scale bits (3 & 4):
+    ctrl1RegValue &= 0xE7;
+    switch (gScl)
+    {
+        case 500:
+            ctrl1RegValue |= (0x1 << 3);
+            settings.gyro.scale = 500;
+            break;
+        case 2000:
+            ctrl1RegValue |= (0x3 << 3);
+            settings.gyro.scale = 2000;
+            break;
+        default: // Otherwise we'll set it to 245 dps (0x0 << 4)
+            settings.gyro.scale = 245;
+            break;
+    }
+    xgWriteByte(CTRL_REG1_G, ctrl1RegValue);
+    
+    calcgRes(); 
+}
+
+void LSM9DS1::setAccelScale(uint8_t aScl)
+{
+    // We need to preserve the other bytes in CTRL_REG6_XL. So, first read it:
+    uint8_t tempRegValue = xgReadByte(CTRL_REG6_XL);
+    // Mask out accel scale bits:
+    tempRegValue &= 0xE7;
+    
+    switch (aScl)
+    {
+        case 4:
+            tempRegValue |= (0x2 << 3);
+            settings.accel.scale = 4;
+            break;
+        case 8:
+            tempRegValue |= (0x3 << 3);
+            settings.accel.scale = 8;
+            break;
+        case 16:
+            tempRegValue |= (0x1 << 3);
+            settings.accel.scale = 16;
+            break;
+        default: // Otherwise it'll be set to 2g (0x0 << 3)
+            settings.accel.scale = 2;
+            break;
+    }
+    xgWriteByte(CTRL_REG6_XL, tempRegValue);
+    
+    // Then calculate a new aRes, which relies on aScale being set correctly:
+    calcaRes();
+}
+
+void LSM9DS1::setMagScale(uint8_t mScl)
+{
+    // We need to preserve the other bytes in CTRL_REG6_XM. So, first read it:
+    uint8_t temp = mReadByte(CTRL_REG2_M);
+    // Then mask out the mag scale bits:
+    temp &= 0xFF^(0x3 << 5);
+    
+    switch (mScl)
+    {
+    case 8:
+        temp |= (0x1 << 5);
+        settings.mag.scale = 8;
+        break;
+    case 12:
+        temp |= (0x2 << 5);
+        settings.mag.scale = 12;
+        break;
+    case 16:
+        temp |= (0x3 << 5);
+        settings.mag.scale = 16;
+        break;
+    default: // Otherwise we'll default to 4 gauss (00)
+        settings.mag.scale = 4;
+        break;
+    }   
+    
+    // And write the new register value back into CTRL_REG6_XM:
+    mWriteByte(CTRL_REG2_M, 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 LSM9DS1::setGyroODR(uint8_t gRate)
+{
+    // Only do this if gRate is not 0 (which would disable the gyro)
+    if ((gRate & 0x07) != 0)
+    {
+        // We need to preserve the other bytes in CTRL_REG1_G. So, first read it:
+        uint8_t temp = xgReadByte(CTRL_REG1_G);
+        // Then mask out the gyro ODR bits:
+        temp &= 0xFF^(0x7 << 5);
+        temp |= (gRate & 0x07) << 5;
+        // Update our settings struct
+        settings.gyro.sampleRate = gRate & 0x07;
+        // And write the new register value back into CTRL_REG1_G:
+        xgWriteByte(CTRL_REG1_G, temp);
+    }
+}
+
+void LSM9DS1::setAccelODR(uint8_t aRate)
+{
+    // Only do this if aRate is not 0 (which would disable the accel)
+    if ((aRate & 0x07) != 0)
+    {
+        // We need to preserve the other bytes in CTRL_REG1_XM. So, first read it:
+        uint8_t temp = xgReadByte(CTRL_REG6_XL);
+        // Then mask out the accel ODR bits:
+        temp &= 0x1F;
+        // Then shift in our new ODR bits:
+        temp |= ((aRate & 0x07) << 5);
+        settings.accel.sampleRate = aRate & 0x07;
+        // And write the new register value back into CTRL_REG1_XM:
+        xgWriteByte(CTRL_REG6_XL, temp);
+    }
+}
+
+void LSM9DS1::setMagODR(uint8_t mRate)
+{
+    // We need to preserve the other bytes in CTRL_REG5_XM. So, first read it:
+    uint8_t temp = mReadByte(CTRL_REG1_M);
+    // Then mask out the mag ODR bits:
+    temp &= 0xFF^(0x7 << 2);
+    // Then shift in our new ODR bits:
+    temp |= ((mRate & 0x07) << 2);
+    settings.mag.sampleRate = mRate & 0x07;
+    // And write the new register value back into CTRL_REG5_XM:
+    mWriteByte(CTRL_REG1_M, temp);
+}
+
+void LSM9DS1::calcgRes()
+{
+    gRes = ((float) settings.gyro.scale) / 32768.0f;
+}
+
+void LSM9DS1::calcaRes()
+{
+    aRes = ((float) settings.accel.scale) / 32768.0f;
+}
+
+void LSM9DS1::calcmRes()
+{
+    //mRes = ((float) settings.mag.scale) / 32768.0;
+    switch (settings.mag.scale)
+    {
+    case 4:
+        mRes = magSensitivity[0];
+        break;
+    case 8:
+        mRes = magSensitivity[1];
+        break;
+    case 12:
+        mRes = magSensitivity[2];
+        break;
+    case 16:
+        mRes = magSensitivity[3];
+        break;
+    }
+    
+}
+
+void LSM9DS1::configInt(interrupt_select interrupt, uint8_t generator,
+                         h_lactive activeLow, pp_od pushPull)
+{
+    // Write to INT1_CTRL or INT2_CTRL. [interupt] should already be one of
+    // those two values.
+    // [generator] should be an OR'd list of values from the interrupt_generators enum
+    xgWriteByte(interrupt, generator);
+    
+    // Configure CTRL_REG8
+    uint8_t temp;
+    temp = xgReadByte(CTRL_REG8);
+    
+    if (activeLow) temp |= (1<<5);
+    else temp &= ~(1<<5);
+    
+    if (pushPull) temp &= ~(1<<4);
+    else temp |= (1<<4);
+    
+    xgWriteByte(CTRL_REG8, temp);
+}
+
+void LSM9DS1::configInactivity(uint8_t duration, uint8_t threshold, bool sleepOn)
+{
+    uint8_t temp = 0;
+    
+    temp = threshold & 0x7F;
+    if (sleepOn) temp |= (1<<7);
+    xgWriteByte(ACT_THS, temp);
+    
+    xgWriteByte(ACT_DUR, duration);
+}
+
+uint8_t LSM9DS1::getInactivity()
+{
+    uint8_t temp = xgReadByte(STATUS_REG_0);
+    temp &= (0x10);
+    return temp;
+}
+
+void LSM9DS1::configAccelInt(uint8_t generator, bool andInterrupts)
+{
+    // Use variables from accel_interrupt_generator, OR'd together to create
+    // the [generator]value.
+    uint8_t temp = generator;
+    if (andInterrupts) temp |= 0x80;
+    xgWriteByte(INT_GEN_CFG_XL, temp);
+}
+
+void LSM9DS1::configAccelThs(uint8_t threshold, lsm9ds1_axis axis, uint8_t duration, bool wait)
+{
+    // Write threshold value to INT_GEN_THS_?_XL.
+    // axis will be 0, 1, or 2 (x, y, z respectively)
+    xgWriteByte(INT_GEN_THS_X_XL + axis, threshold);
+    
+    // Write duration and wait to INT_GEN_DUR_XL
+    uint8_t temp;
+    temp = (duration & 0x7F);
+    if (wait) temp |= 0x80;
+    xgWriteByte(INT_GEN_DUR_XL, temp);
+}
+
+uint8_t LSM9DS1::getAccelIntSrc()
+{
+    uint8_t intSrc = xgReadByte(INT_GEN_SRC_XL);
+    
+    // Check if the IA_XL (interrupt active) bit is set
+    if (intSrc & (1<<6))
+    {
+        return (intSrc & 0x3F);
+    }
+    
+    return 0;
+}
+
+void LSM9DS1::configGyroInt(uint8_t generator, bool aoi, bool latch)
+{
+    // Use variables from accel_interrupt_generator, OR'd together to create
+    // the [generator]value.
+    uint8_t temp = generator;
+    if (aoi) temp |= 0x80;
+    if (latch) temp |= 0x40;
+    xgWriteByte(INT_GEN_CFG_G, temp);
+}
+
+void LSM9DS1::configGyroThs(int16_t threshold, lsm9ds1_axis axis, uint8_t duration, bool wait)
+{
+    uint8_t buffer[2];
+    buffer[0] = (threshold & 0x7F00) >> 8;
+    buffer[1] = (threshold & 0x00FF);
+    // Write threshold value to INT_GEN_THS_?H_G and  INT_GEN_THS_?L_G.
+    // axis will be 0, 1, or 2 (x, y, z respectively)
+    xgWriteByte(INT_GEN_THS_XH_G + (axis * 2), buffer[0]);
+    xgWriteByte(INT_GEN_THS_XH_G + 1 + (axis * 2), buffer[1]);
+    
+    // Write duration and wait to INT_GEN_DUR_XL
+    uint8_t temp;
+    temp = (duration & 0x7F);
+    if (wait) temp |= 0x80;
+    xgWriteByte(INT_GEN_DUR_G, temp);
+}
+
+uint8_t LSM9DS1::getGyroIntSrc()
+{
+    uint8_t intSrc = xgReadByte(INT_GEN_SRC_G);
+    
+    // Check if the IA_G (interrupt active) bit is set
+    if (intSrc & (1<<6))
+    {
+        return (intSrc & 0x3F);
+    }
+    
+    return 0;
+}
+
+void LSM9DS1::configMagInt(uint8_t generator, h_lactive activeLow, bool latch)
+{
+    // Mask out non-generator bits (0-4)
+    uint8_t config = (generator & 0xE0);    
+    // IEA bit is 0 for active-low, 1 for active-high.
+    if (activeLow == INT_ACTIVE_HIGH) config |= (1<<2);
+    // IEL bit is 0 for latched, 1 for not-latched
+    if (!latch) config |= (1<<1);
+    // As long as we have at least 1 generator, enable the interrupt
+    if (generator != 0) config |= (1<<0);
+    
+    mWriteByte(INT_CFG_M, config);
+}
+
+void LSM9DS1::configMagThs(uint16_t threshold)
+{
+    // Write high eight bits of [threshold] to INT_THS_H_M
+    mWriteByte(INT_THS_H_M, uint8_t((threshold & 0x7F00) >> 8));
+    // Write low eight bits of [threshold] to INT_THS_L_M
+    mWriteByte(INT_THS_L_M, uint8_t(threshold & 0x00FF));
+}
+
+uint8_t LSM9DS1::getMagIntSrc()
+{
+    uint8_t intSrc = mReadByte(INT_SRC_M);
+    
+    // Check if the INT (interrupt active) bit is set
+    if (intSrc & (1<<0))
+    {
+        return (intSrc & 0xFE);
+    }
+    
+    return 0;
+}
+
+void LSM9DS1::sleepGyro(bool enable)
+{
+    uint8_t temp = xgReadByte(CTRL_REG9);
+    if (enable) temp |= (1<<6);
+    else temp &= ~(1<<6);
+    xgWriteByte(CTRL_REG9, temp);
+}
+
+void LSM9DS1::enableFIFO(bool enable)
+{
+    uint8_t temp = xgReadByte(CTRL_REG9);
+    if (enable) temp |= (1<<1);
+    else temp &= ~(1<<1);
+    xgWriteByte(CTRL_REG9, temp);
+}
+
+void LSM9DS1::setFIFO(fifoMode_type fifoMode, uint8_t fifoThs)
+{
+    // Limit threshold - 0x1F (31) is the maximum. If more than that was asked
+    // limit it to the maximum.
+    uint8_t threshold = fifoThs <= 0x1F ? fifoThs : 0x1F;
+    xgWriteByte(FIFO_CTRL, ((fifoMode & 0x7) << 5) | (threshold & 0x1F));
+}
+
+uint8_t LSM9DS1::getFIFOSamples()
+{
+    return (xgReadByte(FIFO_SRC) & 0x3F);
+}
+
+void LSM9DS1::constrainScales()
+{
+    if ((settings.gyro.scale != 245) && (settings.gyro.scale != 500) && 
+        (settings.gyro.scale != 2000))
+    {
+        settings.gyro.scale = 245;
+    }
+        
+    if ((settings.accel.scale != 2) && (settings.accel.scale != 4) &&
+        (settings.accel.scale != 8) && (settings.accel.scale != 16))
+    {
+        settings.accel.scale = 2;
+    }
+        
+    if ((settings.mag.scale != 4) && (settings.mag.scale != 8) &&
+        (settings.mag.scale != 12) && (settings.mag.scale != 16))
+    {
+        settings.mag.scale = 4;
+    }
+}
+
+void LSM9DS1::xgWriteByte(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 (settings.device.commInterface == IMU_MODE_I2C) {
+        printf("yo");
+        I2CwriteByte(_xgAddress, subAddress, data);
+    } else if (settings.device.commInterface == IMU_MODE_SPI) {
+        SPIwriteByte(_xgAddress, subAddress, data);
+    }
+}
+
+void LSM9DS1::mWriteByte(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 (settings.device.commInterface == IMU_MODE_I2C)
+        return I2CwriteByte(_mAddress, subAddress, data);
+    else if (settings.device.commInterface == IMU_MODE_SPI)
+        return SPIwriteByte(_mAddress, subAddress, data);
+}
+
+uint8_t LSM9DS1::xgReadByte(uint8_t subAddress)
+{
+    // Whether we're using I2C or SPI, read a byte using the
+    // gyro-specific I2C address or SPI CS pin.
+	
+    if (settings.device.commInterface == IMU_MODE_I2C)
+        return I2CreadByte(_xgAddress, subAddress);
+    else if (settings.device.commInterface == IMU_MODE_SPI)
+        return SPIreadByte(_xgAddress, subAddress);
+		else 
+			return 0;
+}
+
+void LSM9DS1::xgReadBytes(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 (settings.device.commInterface == IMU_MODE_I2C) {
+        I2CreadBytes(_xgAddress, subAddress, dest, count);
+    } else if (settings.device.commInterface == IMU_MODE_SPI) {
+        SPIreadBytes(_xgAddress, subAddress, dest, count);
+    }
+}
+
+uint8_t LSM9DS1::mReadByte(uint8_t subAddress)
+{
+    // Whether we're using I2C or SPI, read a byte using the
+    // accelerometer-specific I2C address or SPI CS pin.
+    if (settings.device.commInterface == IMU_MODE_I2C)
+        return I2CreadByte(_mAddress, subAddress);
+    else if (settings.device.commInterface == IMU_MODE_SPI)
+        return SPIreadByte(_mAddress, subAddress);
+		else 
+			return 0;
+}
+
+void LSM9DS1::mReadBytes(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 (settings.device.commInterface == IMU_MODE_I2C)
+        I2CreadBytes(_mAddress, subAddress, dest, count);
+    else if (settings.device.commInterface == IMU_MODE_SPI)
+        SPIreadBytes(_mAddress, subAddress, dest, count);
+}
+
+void LSM9DS1::initSPI()
+{
+    /* 
+    pinMode(_xgAddress, OUTPUT);
+    digitalWrite(_xgAddress, HIGH);
+    pinMode(_mAddress, OUTPUT);
+    digitalWrite(_mAddress, HIGH);
+    
+    SPI.begin();
+    // Maximum SPI frequency is 10MHz, could divide by 2 here:
+    SPI.setClockDivider(SPI_CLOCK_DIV2);
+    // Data is read and written MSb first.
+    SPI.setBitOrder(MSBFIRST);
+    // Data is captured on rising edge of clock (CPHA = 0)
+    // Base value of the clock is HIGH (CPOL = 1)
+    SPI.setDataMode(SPI_MODE0);
+    */
+}
+
+void LSM9DS1::SPIwriteByte(uint8_t csPin, uint8_t subAddress, uint8_t data)
+{
+    /*
+    digitalWrite(csPin, LOW); // Initiate communication
+    
+    // If write, bit 0 (MSB) should be 0
+    // If single write, bit 1 should be 0
+    SPI.transfer(subAddress & 0x3F); // Send Address
+    SPI.transfer(data); // Send data
+    
+    digitalWrite(csPin, HIGH); // Close communication
+    */
+}
+
+uint8_t LSM9DS1::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 LSM9DS1::SPIreadBytes(uint8_t csPin, uint8_t subAddress,
+                            uint8_t * dest, uint8_t count)
+{
+    // To indicate a read, set bit 0 (msb) of first byte to 1
+    uint8_t rAddress = 0x80 | (subAddress & 0x3F);
+    // Mag SPI port is different. If we're reading multiple bytes, 
+    // set bit 1 to 1. The remaining six bytes are the address to be read
+    if ((csPin == _mAddress) && count > 1)
+        rAddress |= 0x40;
+    
+    /* 
+    digitalWrite(csPin, LOW); // Initiate communication
+    SPI.transfer(rAddress);
+    for (int i=0; i<count; i++)
+    {
+        dest[i] = SPI.transfer(0x00); // Read into destination array
+    }
+    digitalWrite(csPin, HIGH); // Close communication
+    */
+}
+
+void LSM9DS1::initI2C()
+{
+    /* 
+    Wire.begin();   // Initialize I2C library
+    */
+    
+    //already initialized in constructor!
+}
+
+// Wire.h read and write protocols
+void LSM9DS1::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
+    */
+    char temp_data[2] = {subAddress, data};
+    i2c.write(address, temp_data, 2);
+}
+
+uint8_t LSM9DS1::I2CreadByte(uint8_t address, uint8_t subAddress)
+{
+    /* 
+    int timeout = LSM9DS1_COMMUNICATION_TIMEOUT;
+    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(true);             // 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 
+    while ((Wire.available() < 1) && (timeout-- > 0))
+        delay(1);
+    
+    if (timeout <= 0)
+        return 255; //! Bad! 255 will be misinterpreted as a good value.
+    
+    data = Wire.read();                      // Fill Rx buffer with result
+    return data;                             // Return data read from slave register
+    */
+    char data;
+    char temp[1] = {subAddress};
+    
+    i2c.write(address, temp, 1);
+    //i2c.write(address & 0xFE);
+    temp[0] = 0x00;
+    i2c.write(address, temp, 1);
+    //i2c.write( address | 0x01);
+    int a = i2c.read(address, &data, 1);
+    return data;
+}
+
+uint8_t LSM9DS1::I2CreadBytes(uint8_t address, uint8_t subAddress, uint8_t * dest, uint8_t count)
+{  
+    /* 
+    int timeout = LSM9DS1_COMMUNICATION_TIMEOUT;
+    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(true);             // 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() < count) && (timeout-- > 0))
+        delay(1);
+    if (timeout <= 0)
+        return -1;
+    
+    for (int i=0; i<count;)
+    {
+        if (Wire.available())
+        {
+            dest[i++] = Wire.read();
+        }
+    }
+    return count;
+    */
+    int i;
+    char temp_dest[count];
+    char temp[1] = {subAddress};
+    i2c.write(address, temp, 1);
+    i2c.read(address, temp_dest, count);
+    
+    //i2c doesn't take uint8_ts, but rather chars so do this nasty af conversion
+    for (i=0; i < count; i++) {
+        dest[i] = temp_dest[i];    
+    }
+    return count;
+}
+
+
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/LSM9DS1_i2c.h	Wed Feb 23 07:16:58 2022 +0000
@@ -0,0 +1,579 @@
+/******************************************************************************
+SFE_LSM9DS1.h
+SFE_LSM9DS1 Library Header File
+Jim Lindblom @ SparkFun Electronics
+Original Creation Date: February 27, 2015
+https://github.com/sparkfun/LSM9DS1_Breakout
+
+This file prototypes the LSM9DS1 class, implemented in SFE_LSM9DS1.cpp. In
+addition, it defines every register in the LSM9DS1 (both the Gyro and Accel/
+Magnetometer registers).
+
+Development environment specifics:
+    IDE: Arduino 1.6.0
+    Hardware Platform: Arduino Uno
+    LSM9DS1 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.
+******************************************************************************/
+#ifndef __SparkFunLSM9DS1_H__
+#define __SparkFunLSM9DS1_H__
+
+//#if defined(ARDUINO) && ARDUINO >= 100
+//  #include "Arduino.h"
+//#else
+//  #include "WProgram.h"
+//  #include "pins_arduino.h"
+//#endif
+
+#include "mbed.h"
+#include <stdint.h>
+#include "LSM9DS1_Registers.h"
+#include "LSM9DS1_Types.h"
+
+#define LSM9DS1_AG_ADDR(sa0)    ((sa0) == 0 ? 0x6A : 0x6B)
+#define LSM9DS1_M_ADDR(sa1)     ((sa1) == 0 ? 0x1C : 0x1E)
+
+enum lsm9ds1_axis {
+    X_AXIS,
+    Y_AXIS,
+    Z_AXIS,
+    ALL_AXIS
+};
+
+class LSM9DS1
+{
+public:
+    IMUSettings settings;
+    
+    // We'll store the gyro, accel, and magnetometer readings in a series of
+    // public class variables. Each sensor gets three variables -- one for each
+    // axis. Call updateGyro(), updateAcc(), and updateMag() first, before using
+    // these variables!
+    // These values are the RAW signed 16-bit readings from the sensors.
+    int16_t gx, gy, gz; // x, y, and z axis readings of the gyroscope
+    int16_t ax, ay, az; // x, y, and z axis readings of the accelerometer
+    int16_t mx, my, mz; // x, y, and z axis readings of the magnetometer
+    int16_t temperature; // Chip temperature
+    float gBias[3], aBias[3], mBias[3];
+    int16_t gBiasRaw[3], aBiasRaw[3], mBiasRaw[3];
+    
+    /*
+    float gyroX, gyroY, gyroZ; // x, y, and z axis readings of the gyroscope (float value)
+    float accX, accY, accZ; // x, y, and z axis readings of the accelerometer (float value)
+    float magX, magY, magZ; // x, y, and z axis readings of the magnetometer (float value)
+    */
+    
+    // LSM9DS1 -- LSM9DS1 class constructor
+    // The constructor will set up a handful of private variables, and set the
+    // communication mode as well.
+    /**Input:
+    *  - interface = Either IMU_MODE_SPI or IMU_MODE_I2C, whichever you're using
+    *              to talk to the IC.
+    *  - xgAddr = If IMU_MODE_I2C, this is the I2C address of the accel/gyroscope.
+    *              If IMU_MODE_SPI, this is the chip select pin of the gyro (CS_AG)
+    *  - mAddr = If IMU_MODE_I2C, this is the I2C address of the magnetometer.
+    *              If IMU_MODE_SPI, this is the cs pin of the magnetometer (CS_M)
+    
+    */
+    LSM9DS1(PinName sda, PinName scl, uint8_t xgAddr, uint8_t mAddr);
+    LSM9DS1(PinName sda, PinName scl);
+    //LSM9DS1(interface_mode interface, uint8_t xgAddr, uint8_t mAddr);
+    //LSM9DS1();
+       
+    
+    /** begin() -- Initialize the gyro, accelerometer, and magnetometer.
+    *This will set up the scale and output rate of each sensor. The values set
+    * in the IMUSettings struct will take effect after calling this function.
+    */
+    uint16_t begin();
+    
+    float readGyroX();
+    float readGyroY();
+    float readGyroZ();
+    float readAccX();
+    float readAccY();
+    float readAccZ();
+    float readMagX();
+    float readMagY();
+    float readMagZ();
+    
+    void calibrate(bool autoCalc = true);
+    void calibrateMag(bool loadIn = true);
+    void magOffset(uint8_t axis, int16_t offset);
+    
+    /** accelAvailable() -- Polls the accelerometer status register to check
+    * if new data is available.
+    * Output:  1 - New data available
+    *          0 - No new data available
+    */
+    uint8_t accelAvailable();
+    
+    /** gyroAvailable() -- Polls the gyroscope status register to check
+    * if new data is available.
+    * Output:  1 - New data available
+    *          0 - No new data available
+    */
+    uint8_t gyroAvailable();
+    
+    /** gyroAvailable() -- Polls the temperature status register to check
+    * if new data is available.
+    * Output:  1 - New data available
+    *          0 - No new data available
+    */
+    uint8_t tempAvailable();
+    
+    /** magAvailable() -- Polls the accelerometer status register to check
+    * if new data is available.
+    * Input:
+    *  - axis can be either X_AXIS, Y_AXIS, Z_AXIS, to check for new data
+    *    on one specific axis. Or ALL_AXIS (default) to check for new data
+    *    on all axes.
+    * Output:  1 - New data available
+    *          0 - No new data available
+    */
+    uint8_t magAvailable(lsm9ds1_axis axis = ALL_AXIS);
+    
+    /** updateGyro() -- Read the gyroscope output registers.
+    * This function will read all six gyroscope output registers.
+    * The readings are stored in the class' gx, gy, and gz variables. Read
+    * those _after_ calling updateGyro().
+    */
+    void updateGyro();
+    
+    /** int16_t updateGyro(axis) -- Read a specific axis of the gyroscope.
+    * [axis] can be any of X_AXIS, Y_AXIS, or Z_AXIS.
+    * Input:
+    *  - axis: can be either X_AXIS, Y_AXIS, or Z_AXIS.
+    * Output:
+    *  A 16-bit signed integer with sensor data on requested axis.
+    */
+    int16_t updateGyro(lsm9ds1_axis axis);
+    
+    /** updateAcc() -- Read the accelerometer output registers.
+    * This function will read all six accelerometer output registers.
+    * The readings are stored in the class' ax, ay, and az variables. Read
+    * those _after_ calling updateAcc().
+    */
+    void updateAcc();
+    
+    /** int16_t updateAcc(axis) -- Read a specific axis of the accelerometer.
+    * [axis] can be any of X_AXIS, Y_AXIS, or Z_AXIS.
+    * Input:
+    *  - axis: can be either X_AXIS, Y_AXIS, or Z_AXIS.
+    * Output:
+    *  A 16-bit signed integer with sensor data on requested axis.
+    */
+    int16_t updateAcc(lsm9ds1_axis axis);
+    
+    /** updateMag() -- Read the magnetometer output registers.
+    * This function will read all six magnetometer output registers.
+    * The readings are stored in the class' mx, my, and mz variables. Read
+    * those _after_ calling updateMag().
+    */
+    void updateMag();
+    
+    /** int16_t updateMag(axis) -- Read a specific axis of the magnetometer.
+    * [axis] can be any of X_AXIS, Y_AXIS, or Z_AXIS.
+    * Input:
+    *  - axis: can be either X_AXIS, Y_AXIS, or Z_AXIS.
+    * Output:
+    *  A 16-bit signed integer with sensor data on requested axis.
+    */
+    int16_t updateMag(lsm9ds1_axis axis);
+
+    /** readTemp() -- Read the temperature output register.
+    * This function will read two temperature output registers.
+    * The combined readings are stored in the class' temperature variables. Read
+    * those _after_ calling readTemp().
+    */
+    void readTemp();
+    
+    /** calcGyro() -- Convert from RAW signed 16-bit value to degrees per second
+    * This function reads in a signed 16-bit value and returns the scaled
+    * DPS. This function relies on gScale and gRes being correct.
+    * Input:
+    *  - gyro = A signed 16-bit raw reading from the gyroscope.
+    */
+    float calcGyro(int16_t gyro);
+    
+    /** calcAccel() -- Convert from RAW signed 16-bit value to gravity (g's).
+    * This function reads in a signed 16-bit value and returns the scaled
+    * g's. This function relies on aScale and aRes being correct.
+    * Input:
+    *  - accel = A signed 16-bit raw reading from the accelerometer.
+    */
+    float calcAccel(int16_t accel);
+    
+    /** calcMag() -- Convert from RAW signed 16-bit value to Gauss (Gs)
+    * This function reads in a signed 16-bit value and returns the scaled
+    * Gs. This function relies on mScale and mRes being correct.
+    * Input:
+    *  - mag = A signed 16-bit raw reading from the magnetometer.
+    */
+    float calcMag(int16_t mag);
+    
+    /** setGyroScale() -- Set the full-scale range of the gyroscope.
+    * This function can be called to set the scale of the gyroscope to 
+    * 245, 500, or 200 degrees per second.
+    * Input:
+    *  - gScl = The desired gyroscope scale. Must be one of three possible
+    *      values from the gyro_scale.
+    */
+    void setGyroScale(uint16_t gScl);
+    
+    /** setAccelScale() -- Set the full-scale range of the accelerometer.
+    * This function can be called to set the scale of the accelerometer to
+    * 2, 4, 6, 8, or 16 g's.
+    * Input:
+    *  - aScl = The desired accelerometer scale. Must be one of five possible
+    *      values from the accel_scale.
+    */
+    void setAccelScale(uint8_t aScl);
+    
+    /** setMagScale() -- Set the full-scale range of the magnetometer.
+    * This function can be called to set the scale of the magnetometer to
+    * 2, 4, 8, or 12 Gs.
+    * Input:
+    *  - mScl = The desired magnetometer scale. Must be one of four possible
+    *      values from the mag_scale.
+    */
+    void setMagScale(uint8_t mScl);
+    
+    /** setGyroODR() -- Set the output data rate and bandwidth of the gyroscope
+    * Input:
+    *  - gRate = The desired output rate and cutoff frequency of the gyro.
+    */
+    void setGyroODR(uint8_t gRate);
+    
+    // setAccelODR() -- Set the output data rate of the accelerometer
+    // Input:
+    //  - aRate = The desired output rate of the accel.
+    void setAccelODR(uint8_t aRate);    
+    
+    // setMagODR() -- Set the output data rate of the magnetometer
+    // Input:
+    //  - mRate = The desired output rate of the mag.
+    void setMagODR(uint8_t mRate);
+    
+    // configInactivity() -- Configure inactivity interrupt parameters
+    // Input:
+    //  - duration = Inactivity duration - actual value depends on gyro ODR
+    //  - threshold = Activity Threshold
+    //  - sleepOn = Gyroscope operating mode during inactivity.
+    //    true: gyroscope in sleep mode
+    //    false: gyroscope in power-down
+    void configInactivity(uint8_t duration, uint8_t threshold, bool sleepOn);
+    
+    // configAccelInt() -- Configure Accelerometer Interrupt Generator
+    // Input:
+    //  - generator = Interrupt axis/high-low events
+    //    Any OR'd combination of ZHIE_XL, ZLIE_XL, YHIE_XL, YLIE_XL, XHIE_XL, XLIE_XL
+    //  - andInterrupts = AND/OR combination of interrupt events
+    //    true: AND combination
+    //    false: OR combination
+    void configAccelInt(uint8_t generator, bool andInterrupts = false);
+    
+    // configAccelThs() -- Configure the threshold of an accelereomter axis
+    // Input:
+    //  - threshold = Interrupt threshold. Possible values: 0-255.
+    //    Multiply by 128 to get the actual raw accel value.
+    //  - axis = Axis to be configured. Either X_AXIS, Y_AXIS, or Z_AXIS
+    //  - duration = Duration value must be above or below threshold to trigger interrupt
+    //  - wait = Wait function on duration counter
+    //    true: Wait for duration samples before exiting interrupt
+    //    false: Wait function off
+    void configAccelThs(uint8_t threshold, lsm9ds1_axis axis, uint8_t duration = 0, bool wait = 0);
+    
+    // configGyroInt() -- Configure Gyroscope Interrupt Generator
+    // Input:
+    //  - generator = Interrupt axis/high-low events
+    //    Any OR'd combination of ZHIE_G, ZLIE_G, YHIE_G, YLIE_G, XHIE_G, XLIE_G
+    //  - aoi = AND/OR combination of interrupt events
+    //    true: AND combination
+    //    false: OR combination
+    //  - latch: latch gyroscope interrupt request.
+    void configGyroInt(uint8_t generator, bool aoi, bool latch);
+    
+    // configGyroThs() -- Configure the threshold of a gyroscope axis
+    // Input:
+    //  - threshold = Interrupt threshold. Possible values: 0-0x7FF.
+    //    Value is equivalent to raw gyroscope value.
+    //  - axis = Axis to be configured. Either X_AXIS, Y_AXIS, or Z_AXIS
+    //  - duration = Duration value must be above or below threshold to trigger interrupt
+    //  - wait = Wait function on duration counter
+    //    true: Wait for duration samples before exiting interrupt
+    //    false: Wait function off
+    void configGyroThs(int16_t threshold, lsm9ds1_axis axis, uint8_t duration, bool wait);
+    
+    // configInt() -- Configure INT1 or INT2 (Gyro and Accel Interrupts only)
+    // Input:
+    //  - interrupt = Select INT1 or INT2
+    //    Possible values: XG_INT1 or XG_INT2
+    //  - generator = Or'd combination of interrupt generators.
+    //    Possible values: INT_DRDY_XL, INT_DRDY_G, INT1_BOOT (INT1 only), INT2_DRDY_TEMP (INT2 only)
+    //    INT_FTH, INT_OVR, INT_FSS5, INT_IG_XL (INT1 only), INT1_IG_G (INT1 only), INT2_INACT (INT2 only)
+    //  - activeLow = Interrupt active configuration
+    //    Can be either INT_ACTIVE_HIGH or INT_ACTIVE_LOW
+    //  - pushPull =  Push-pull or open drain interrupt configuration
+    //    Can be either INT_PUSH_PULL or INT_OPEN_DRAIN
+    void configInt(interrupt_select interupt, uint8_t generator,
+                   h_lactive activeLow = INT_ACTIVE_LOW, pp_od pushPull = INT_PUSH_PULL);
+                   
+    /** configMagInt() -- Configure Magnetometer Interrupt Generator
+    * Input:
+    *  - generator = Interrupt axis/high-low events
+    *    Any OR'd combination of ZIEN, YIEN, XIEN
+    *  - activeLow = Interrupt active configuration
+    *    Can be either INT_ACTIVE_HIGH or INT_ACTIVE_LOW
+    *  - latch: latch gyroscope interrupt request.
+    */  
+    void configMagInt(uint8_t generator, h_lactive activeLow, bool latch = true);
+    
+    /** configMagThs() -- Configure the threshold of a gyroscope axis
+    * Input:
+    *  - threshold = Interrupt threshold. Possible values: 0-0x7FF.
+    *    Value is equivalent to raw magnetometer value.
+    */
+    void configMagThs(uint16_t threshold);
+    
+    //! getGyroIntSrc() -- Get contents of Gyroscope interrupt source register
+    uint8_t getGyroIntSrc();
+    
+    //! getGyroIntSrc() -- Get contents of accelerometer interrupt source register
+    uint8_t getAccelIntSrc();
+    
+    //! getGyroIntSrc() -- Get contents of magnetometer interrupt source register
+    uint8_t getMagIntSrc();
+    
+    //! getGyroIntSrc() -- Get status of inactivity interrupt
+    uint8_t getInactivity();
+    
+    /** sleepGyro() -- Sleep or wake the gyroscope
+    * Input:
+    *  - enable: True = sleep gyro. False = wake gyro.
+    */
+    void sleepGyro(bool enable = true);
+    
+    /** enableFIFO() - Enable or disable the FIFO
+    * Input:
+    *  - enable: true = enable, false = disable.
+    */
+    void enableFIFO(bool enable = true);
+    
+    /** setFIFO() - Configure FIFO mode and Threshold
+    * Input:
+    *  - fifoMode: Set FIFO mode to off, FIFO (stop when full), continuous, bypass
+    *    Possible inputs: FIFO_OFF, FIFO_THS, FIFO_CONT_TRIGGER, FIFO_OFF_TRIGGER, FIFO_CONT
+    *  - fifoThs: FIFO threshold level setting
+    *    Any value from 0-0x1F is acceptable.
+    */
+    void setFIFO(fifoMode_type fifoMode, uint8_t fifoThs);
+    
+    //! getFIFOSamples() - Get number of FIFO samples
+    uint8_t getFIFOSamples();
+        
+
+protected:  
+    // x_mAddress and gAddress store the I2C address or SPI chip select pin
+    // for each sensor.
+    uint8_t _mAddress, _xgAddress;
+    
+    // gRes, aRes, and mRes store the current resolution for each sensor. 
+    // Units of these values would be DPS (or g's or Gs's) per ADC tick.
+    // This value is calculated as (sensor scale) / (2^15).
+    float gRes, aRes, mRes;
+    
+    // _autoCalc keeps track of whether we're automatically subtracting off
+    // accelerometer and gyroscope bias calculated in calibrate().
+    bool _autoCalc;
+    
+    // init() -- Sets up gyro, accel, and mag settings to default.
+    // - interface - Sets the interface mode (IMU_MODE_I2C or IMU_MODE_SPI)
+    // - xgAddr - Sets either the I2C address of the accel/gyro or SPI chip 
+    //   select pin connected to the CS_XG pin.
+    // - mAddr - Sets either the I2C address of the magnetometer or SPI chip 
+    //   select pin connected to the CS_M pin.
+    void init(interface_mode interface, uint8_t xgAddr, uint8_t mAddr);
+    
+    // initGyro() -- Sets up the gyroscope to begin reading.
+    // This function steps through all five gyroscope control registers.
+    // Upon exit, the following parameters will be set:
+    //  - CTRL_REG1_G = 0x0F: Normal operation mode, all axes enabled. 
+    //      95 Hz ODR, 12.5 Hz cutoff frequency.
+    //  - CTRL_REG2_G = 0x00: HPF set to normal mode, cutoff frequency
+    //      set to 7.2 Hz (depends on ODR).
+    //  - CTRL_REG3_G = 0x88: Interrupt enabled on INT_G (set to push-pull and
+    //      active high). Data-ready output enabled on DRDY_G.
+    //  - CTRL_REG4_G = 0x00: Continuous update mode. Data LSB stored in lower
+    //      address. Scale set to 245 DPS. SPI mode set to 4-wire.
+    //  - CTRL_REG5_G = 0x00: FIFO disabled. HPF disabled.
+    void initGyro();
+    
+    // initAccel() -- Sets up the accelerometer to begin reading.
+    // This function steps through all accelerometer related control registers.
+    // Upon exit these registers will be set as:
+    //  - CTRL_REG0_XM = 0x00: FIFO disabled. HPF bypassed. Normal mode.
+    //  - CTRL_REG1_XM = 0x57: 100 Hz data rate. Continuous update.
+    //      all axes enabled.
+    //  - CTRL_REG2_XM = 0x00:  2g scale. 773 Hz anti-alias filter BW.
+    //  - CTRL_REG3_XM = 0x04: Accel data ready signal on INT1_XM pin.
+    void initAccel();
+    
+    // initMag() -- Sets up the magnetometer to begin reading.
+    // This function steps through all magnetometer-related control registers.
+    // Upon exit these registers will be set as:
+    //  - CTRL_REG4_XM = 0x04: Mag data ready signal on INT2_XM pin.
+    //  - CTRL_REG5_XM = 0x14: 100 Hz update rate. Low resolution. Interrupt
+    //      requests don't latch. Temperature sensor disabled.
+    //  - CTRL_REG6_XM = 0x00:  2 Gs scale.
+    //  - CTRL_REG7_XM = 0x00: Continuous conversion mode. Normal HPF mode.
+    //  - INT_CTRL_REG_M = 0x09: Interrupt active-high. Enable interrupts.
+    void initMag();
+    
+    // gReadByte() -- Reads a byte from a specified gyroscope register.
+    // Input:
+    //  - subAddress = Register to be read from.
+    // Output:
+    //  - An 8-bit value read from the requested address.
+    uint8_t mReadByte(uint8_t subAddress);
+    
+    // gReadBytes() -- Reads a number of bytes -- beginning at an address
+    // and incrementing from there -- from the gyroscope.
+    // Input:
+    //  - subAddress = Register to be read from.
+    //  - * dest = A pointer to an array of uint8_t's. Values read will be
+    //      stored in here on return.
+    //  - count = The number of bytes to be read.
+    // Output: No value is returned, but the `dest` array will store
+    //  the data read upon exit.
+    void mReadBytes(uint8_t subAddress, uint8_t * dest, uint8_t count);
+    
+    // gWriteByte() -- Write a byte to a register in the gyroscope.
+    // Input:
+    //  - subAddress = Register to be written to.
+    //  - data = data to be written to the register.
+    void mWriteByte(uint8_t subAddress, uint8_t data);
+    
+    // xmReadByte() -- Read a byte from a register in the accel/mag sensor
+    // Input:
+    //  - subAddress = Register to be read from.
+    // Output:
+    //  - An 8-bit value read from the requested register.
+    uint8_t xgReadByte(uint8_t subAddress);
+    
+    // xmReadBytes() -- Reads a number of bytes -- beginning at an address
+    // and incrementing from there -- from the accelerometer/magnetometer.
+    // Input:
+    //  - subAddress = Register to be read from.
+    //  - * dest = A pointer to an array of uint8_t's. Values read will be
+    //      stored in here on return.
+    //  - count = The number of bytes to be read.
+    // Output: No value is returned, but the `dest` array will store
+    //  the data read upon exit.
+    void xgReadBytes(uint8_t subAddress, uint8_t * dest, uint8_t count);
+    
+    // xmWriteByte() -- Write a byte to a register in the accel/mag sensor.
+    // Input:
+    //  - subAddress = Register to be written to.
+    //  - data = data to be written to the register.
+    void xgWriteByte(uint8_t subAddress, uint8_t data);
+    
+    // calcgRes() -- Calculate the resolution of the gyroscope.
+    // This function will set the value of the gRes variable. gScale must
+    // be set prior to calling this function.
+    void calcgRes();
+    
+    // calcmRes() -- Calculate the resolution of the magnetometer.
+    // This function will set the value of the mRes variable. mScale must
+    // be set prior to calling this function.
+    void calcmRes();
+    
+    // calcaRes() -- Calculate the resolution of the accelerometer.
+    // This function will set the value of the aRes variable. aScale must
+    // be set prior to calling this function.
+    void calcaRes();
+    
+    //////////////////////
+    // Helper Functions //
+    //////////////////////
+    void constrainScales();
+    
+    ///////////////////
+    // SPI Functions //
+    ///////////////////
+    // initSPI() -- Initialize the SPI hardware.
+    // This function will setup all SPI pins and related hardware.
+    void initSPI();
+    
+    // SPIwriteByte() -- Write a byte out of SPI to a register in the device
+    // Input:
+    //  - csPin = The chip select pin of the slave device.
+    //  - subAddress = The register to be written to.
+    //  - data = Byte to be written to the register.
+    void SPIwriteByte(uint8_t csPin, uint8_t subAddress, uint8_t data);
+    
+    // SPIreadByte() -- Read a single byte from a register over SPI.
+    // Input:
+    //  - csPin = The chip select pin of the slave device.
+    //  - subAddress = The register to be read from.
+    // Output:
+    //  - The byte read from the requested address.
+    uint8_t SPIreadByte(uint8_t csPin, uint8_t subAddress);
+    
+    // SPIreadBytes() -- Read a series of bytes, starting at a register via SPI
+    // Input:
+    //  - csPin = The chip select pin of a slave device.
+    //  - subAddress = The register to begin reading.
+    //  - * dest = Pointer to an array where we'll store the readings.
+    //  - count = Number of registers to be read.
+    // Output: No value is returned by the function, but the registers read are
+    //      all stored in the *dest array given.
+    void SPIreadBytes(uint8_t csPin, uint8_t subAddress, 
+                            uint8_t * dest, uint8_t count);
+    
+    ///////////////////
+    // I2C Functions //
+    ///////////////////
+    // initI2C() -- Initialize the I2C hardware.
+    // This function will setup all I2C pins and related hardware.
+    void initI2C();
+    
+    // I2CwriteByte() -- Write a byte out of I2C to a register in the device
+    // Input:
+    //  - address = The 7-bit I2C address of the slave device.
+    //  - subAddress = The register to be written to.
+    //  - data = Byte to be written to the register.
+    void I2CwriteByte(uint8_t address, uint8_t subAddress, uint8_t data);
+    
+    // I2CreadByte() -- Read a single byte from a register over I2C.
+    // Input:
+    //  - address = The 7-bit I2C address of the slave device.
+    //  - subAddress = The register to be read from.
+    // Output:
+    //  - The byte read from the requested address.
+    uint8_t I2CreadByte(uint8_t address, uint8_t subAddress);
+    
+    // I2CreadBytes() -- Read a series of bytes, starting at a register via SPI
+    // Input:
+    //  - address = The 7-bit I2C address of the slave device.
+    //  - subAddress = The register to begin reading.
+    //  - * dest = Pointer to an array where we'll store the readings.
+    //  - count = Number of registers to be read.
+    // Output: No value is returned by the function, but the registers read are
+    //      all stored in the *dest array given.
+    uint8_t I2CreadBytes(uint8_t address, uint8_t subAddress, uint8_t * dest, uint8_t count);
+    
+private:
+    I2C i2c;
+    float gyroX, gyroY, gyroZ; // x, y, and z axis readings of the gyroscope (float value)
+    float accX, accY, accZ; // x, y, and z axis readings of the accelerometer (float value)
+    float magX, magY, magZ; // x, y, and z axis readings of the magnetometer (float value)
+};
+
+#endif // SFE_LSM9DS1_H //
+
+