Revision 0:32b177f0030e, committed 2015-12-05

Comitter:

olimexsmart

Date:

Sat Dec 05 16:23:36 2015 +0000

Commit message:

What in this world I am supposed to type here?

Changed in this revision

diff -r 000000000000 -r 32b177f0030e AHRS_example.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/AHRS_example.cpp	Sat Dec 05 16:23:36 2015 +0000
@@ -0,0 +1,448 @@
+#include "LSM9DS0_mbed.h"
+#include "mbed.h"
+
+#define INT1    PB_3
+#define INT2    PA_10
+#define DR_DYG  PB_5
+
+#define SDA PB_9
+#define SCL PB_8
+
+///////////////////////
+// Example I2C Setup //
+///////////////////////
+// SDO_XM and SDO_G are both grounded, so our addresses are:
+#define LSM9DS0_XM  0x1D // Would be 0x1E if SDO_XM is LOW
+#define LSM9DS0_G   0x6B // Would be 0x6A if SDO_G is LOW
+
+// Create an instance of the LSM9DS0 library called `dof` the
+// parameters for this constructor are:
+// [I2C SDA], [I2C SCL],[gyro I2C address],[xm I2C add.]
+LSM9DS0 dof(SDA, SCL, LSM9DS0_G, LSM9DS0_XM);
+
+///////////////////////////////////
+// Interrupt Handler Definitions //
+///////////////////////////////////
+DigitalIn INT1XM(INT1);
+DigitalIn INT2XM(INT2);
+DigitalIn DRDYG(DR_DYG);
+
+// global constants for 9 DoF fusion and AHRS (Attitude and Heading Reference System)
+#define GyroMeasError PI * (40.0f / 180.0f)       // gyroscope measurement error in rads/s (shown as 3 deg/s)
+#define GyroMeasDrift PI * (0.0f / 180.0f)      // gyroscope measurement drift in rad/s/s (shown as 0.0 deg/s/s)
+// There is a tradeoff in the beta parameter between accuracy and response speed.
+// In the original Madgwick study, beta of 0.041 (corresponding to GyroMeasError of 2.7 degrees/s) was found to give optimal accuracy.
+// However, with this value, the LSM9SD0 response time is about 10 seconds to a stable initial quaternion.
+// Subsequent changes also require a longish lag time to a stable output, not fast enough for a quadcopter or robot car!
+// By increasing beta (GyroMeasError) by about a factor of fifteen, the response time constant is reduced to ~2 sec
+// I haven't noticed any reduction in solution accuracy. This is essentially the I coefficient in a PID control sense;
+// the bigger the feedback coefficient, the faster the solution converges, usually at the expense of accuracy.
+// In any case, this is the free parameter in the Madgwick filtering and fusion scheme.
+#define beta sqrt(3.0f / 4.0f) * GyroMeasError   // compute beta
+#define zeta sqrt(3.0f / 4.0f) * GyroMeasDrift   // compute zeta, the other free parameter in the Madgwick scheme usually set to a small or zero value
+#define Kp 2.0f * 5.0f // these are the free parameters in the Mahony filter and fusion scheme, Kp for proportional feedback, Ki for integral
+#define Ki 0.0f
+const float  PI = 3.14159265358979f;
+
+Timer t1;   //Integration timer
+Timer t2;   //Print timer
+Serial pc(SERIAL_TX, SERIAL_RX);
+DigitalOut myled(LED1);
+float pitch, yaw, roll, heading;
+float deltat = 0.0f;        // integration interval for both filter schemes
+
+
+float abias[3] = {0, 0, 0}, gbias[3] = {0, 0, 0};
+float ax, ay, az, gx, gy, gz, mx, my, mz; // variables to hold latest sensor data values
+float q[4] = {1.0f, 0.0f, 0.0f, 0.0f};    // vector to hold quaternion
+float eInt[3] = {0.0f, 0.0f, 0.0f};       // vector to hold integral error for Mahony method
+float temperature;
+
+//////////////////////////////////
+//      FUNCTION DECLARATION    //
+//////////////////////////////////
+void setup();
+void loop();
+void MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz);
+void MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz);
+void dataGyro();
+void dataAccel();
+void dataMag();
+
+//////////////////////////////////
+//             MAIN             //
+//////////////////////////////////
+int main()
+{
+    setup();  //Setup sensor and Serial
+    pc.printf("Setup Done\n\r");
+
+
+    while (true)
+        loop();
+}
+
+
+//////////////////////////////////
+//          FUNCTION BODY       //
+//////////////////////////////////
+void dataGyro()
+{
+    dof.readGyro();           // Read raw gyro data
+    gx = dof.calcGyro(dof.gx) - gbias[0];   // Convert to degrees per seconds, remove gyro biases
+    gy = dof.calcGyro(dof.gy) - gbias[1];
+    gz = dof.calcGyro(dof.gz) - gbias[2];
+}
+void dataAccel()
+{
+    dof.readAccel();         // Read raw accelerometer data
+    ax = dof.calcAccel(dof.ax) - abias[0];   // Convert to g's, remove accelerometer biases
+    ay = dof.calcAccel(dof.ay) - abias[1];
+    az = dof.calcAccel(dof.az) - abias[2];
+}
+void dataMag()
+{
+    dof.readMag();           // Read raw magnetometer data
+    mx = dof.calcMag(dof.mx);     // Convert to Gauss and correct for calibration
+    my = dof.calcMag(dof.my);
+    mz = dof.calcMag(dof.mz);
+}
+void setup()
+{
+    pc.baud(115200); // Start serial at 115200 bps
+    myled = true;
+    /*//Interrupt
+    INT1XM.rise(&dataAccel);
+    INT2XM.rise(&dataMag);
+    DRDYG.rise(&dataGyro);
+    */
+    // begin() returns a 16-bit value which includes both the gyro
+    // and accelerometers WHO_AM_I response. You can check this to
+    // make sure communication was successful.
+    uint16_t status = dof.begin();
+
+    pc.printf("LSM9DS0 WHO_AM_I's returned: ");
+    pc.printf("0x%X\t", status);
+    pc.printf("Should be 0x49D4");
+    pc.printf("\n\r");
+
+
+// Set data output ranges; choose lowest ranges for maximum resolution
+// Accelerometer scale can be: A_SCALE_2G, A_SCALE_4G, A_SCALE_6G, A_SCALE_8G, or A_SCALE_16G
+    dof.setAccelScale(dof.A_SCALE_2G);
+// Gyro scale can be:  G_SCALE__245, G_SCALE__500, or G_SCALE__2000DPS
+    dof.setGyroScale(dof.G_SCALE_245DPS);
+// Magnetometer scale can be: M_SCALE_2GS, M_SCALE_4GS, M_SCALE_8GS, M_SCALE_12GS
+    dof.setMagScale(dof.M_SCALE_2GS);
+
+// Set output data rates
+// Accelerometer output data rate (ODR) can be: A_ODR_3125 (3.225 Hz), A_ODR_625 (6.25 Hz), A_ODR_125 (12.5 Hz), A_ODR_25, A_ODR_50,
+//                                              A_ODR_100,  A_ODR_200, A_ODR_400, A_ODR_800, A_ODR_1600 (1600 Hz)
+    dof.setAccelODR(dof.A_ODR_200); // Set accelerometer update rate at 100 Hz
+// Accelerometer anti-aliasing filter rate can be 50, 194, 362, or 763 Hz
+// Anti-aliasing acts like a low-pass filter allowing oversampling of accelerometer and rejection of high-frequency spurious noise.
+// Strategy here is to effectively oversample accelerometer at 100 Hz and use a 50 Hz anti-aliasing (low-pass) filter frequency
+// to get a smooth ~150 Hz filter update rate
+    dof.setAccelABW(dof.A_ABW_50); // Choose lowest filter setting for low noise
+
+// Gyro output data rates can be: 95 Hz (bandwidth 12.5 or 25 Hz), 190 Hz (bandwidth 12.5, 25, 50, or 70 Hz)
+//                                 380 Hz (bandwidth 20, 25, 50, 100 Hz), or 760 Hz (bandwidth 30, 35, 50, 100 Hz)
+    dof.setGyroODR(dof.G_ODR_190_BW_125);  // Set gyro update rate to 190 Hz with the smallest bandwidth for low noise
+
+// Magnetometer output data rate can be: 3.125 (ODR_3125), 6.25 (ODR_625), 12.5 (ODR_125), 25, 50, or 100 Hz
+    dof.setMagODR(dof.M_ODR_125); // Set magnetometer to update every 80 ms
+
+// Use the FIFO mode to average accelerometer and gyro readings to calculate the biases, which can then be removed from
+// all subsequent measurements.
+    dof.calLSM9DS0(gbias, abias);
+
+// Start timers to get integration time and print time
+    t2.start();
+    t1.start();
+    dataGyro();
+    dataAccel();
+    dataMag();
+}
+
+void loop()
+{
+    //Couldn't manage to get these in interrupt, the interrupt won't fire. It isn't so nececesary indeed.
+    if(INT1XM.read())
+        dataAccel();
+    if(INT2XM.read()) 
+    {
+        dataMag();
+       // dof.readTemp(); Can't get temp reading from a Sparkfun breakout board, the problem is not just mine.
+        //temperature = 21.0 + (float) dof.temperature/8.0f; // slope is 8 LSB per degree C, just guessing at the intercept
+    }
+    if(DRDYG.read())
+        dataGyro();
+
+    deltat = t1.read(); // set integration time by time elapsed since last filter update
+    t1.reset();
+
+    // Sensors x- and y-axes are aligned but magnetometer z-axis (+ down) is opposite to z-axis (+ up) of accelerometer and gyro!
+    // This is ok by aircraft orientation standards!
+    // Pass gyro rate as rad/s
+    MadgwickQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, mx, my, mz);
+//MahonyQuaternionUpdate(ax, ay, az, gx*PI/180.0f, gy*PI/180.0f, gz*PI/180.0f, mx, my, mz);
+
+
+    // Serial print at 0.5 s rate independent of data rates
+    if (t2.read() > 1.0f) {
+        t2.reset();
+
+        myled = !myled;
+
+        pc.printf("%f\t%f\t%f\n\r", ax, ay, az);
+        pc.printf("%f\t%f\t%f\n\r", gx, gy, gz);
+        pc.printf("%f\t%f\t%f\n\r", mx, my, mz);
+        /*
+         // Define output variables from updated quaternion---these are Tait-Bryan angles, commonly used in aircraft orientation.
+         // In this coordinate system, the positive z-axis is down toward Earth.
+         // Yaw is the angle between Sensor x-axis and Earth magnetic North (or true North if corrected for local declination),
+         // looking down on the sensor positive yaw is counterclockwise.
+         // Pitch is angle between sensor x-axis and Earth ground plane, toward the Earth is positive, up toward the sky is negative.
+         // Roll is angle between sensor y-axis and Earth ground plane, y-axis up is positive roll.
+         // These arise from the definition of the homogeneous rotation matrix constructed from quaternions.
+         // Tait-Bryan angles as well as Euler angles are non-commutative; that is, to get the correct orientation the rotations must be
+         // applied in the correct order which for this configuration is yaw, pitch, and then roll.
+         // For more see http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles which has additional links.
+         */
+        yaw   = atan2(2.0f * (q[1] * q[2] + q[0] * q[3]), q[0] * q[0] + q[1] * q[1] - q[2] * q[2] - q[3] * q[3]);
+        pitch = -asin(2.0f * (q[1] * q[3] - q[0] * q[2]));
+        roll  = atan2(2.0f * (q[0] * q[1] + q[2] * q[3]), q[0] * q[0] - q[1] * q[1] - q[2] * q[2] + q[3] * q[3]);
+        pitch *= 180.0f / PI;
+        yaw   *= 180.0f / PI;
+        roll  *= 180.0f / PI;
+        //yaw   -= 13.8; // Declination at Danville, California is 13 degrees 48 minutes and 47 seconds on 2014-04-04
+
+/*
+        pc.printf("Temperature = ");
+        pc.printf("%d\n\r", dof.temperature);
+*/
+        //Angles print
+        pc.printf("Yaw, Pitch, Roll: ");
+        pc.printf("%f", yaw);
+        pc.printf(", ");
+        pc.printf("%f", pitch);
+        pc.printf(", ");
+        pc.printf("%f\n\r", roll);
+
+        //Update rate print
+        pc.printf("Filter rate = ");
+        pc.printf("%f\n\r", 1.0f/deltat);
+
+        /*
+        // The filter update rate can be increased by reducing the rate of data reading. The optimal implementation is
+        // one which balances the competing rates so they are about the same; that is, the filter updates the sensor orientation
+        // at about the same rate the data is changing. Of course, other implementations are possible. One might consider
+        // updating the filter at twice the average new data rate to allow for finite filter convergence times.
+        // The filter update rate is determined mostly by the mathematical steps in the respective algorithms,
+        // the processor speed (8 MHz for the 3.3V Pro Mini), and the sensor ODRs, especially the magnetometer ODR:
+        // smaller ODRs for the magnetometer produce the above rates, maximum magnetometer ODR of 100 Hz produces
+        // filter update rates of ~110 and ~135 Hz for the Madgwick and Mahony schemes, respectively.
+        // This is presumably because the magnetometer read takes longer than the gyro or accelerometer reads.
+        // With low ODR settings of 100 Hz, 95 Hz, and 6.25 Hz for the accelerometer, gyro, and magnetometer, respectively,
+        // the filter is updating at a ~150 Hz rate using the Madgwick scheme and ~200 Hz using the Mahony scheme.
+        // These filter update rates should be fast enough to maintain accurate platform orientation for
+        // stabilization control of a fast-moving robot or quadcopter. Compare to the update rate of 200 Hz
+        // produced by the on-board Digital Motion Processor of Invensense's MPU6050 6 DoF and MPU9150 9DoF sensors.
+        // The 3.3 V 8 MHz Pro Mini is doing pretty well!
+        */
+    }
+}
+
+
+
+
+// Implementation of Sebastian Madgwick's "...efficient orientation filter for... inertial/magnetic sensor arrays"
+// (see http://www.x-io.co.uk/category/open-source/ for examples and more details)
+// which fuses acceleration, rotation rate, and magnetic moments to produce a quaternion-based estimate of absolute
+// device orientation -- which can be converted to yaw, pitch, and roll. Useful for stabilizing quadcopters, etc.
+// The performance of the orientation filter is at least as good as conventional Kalman-based filtering algorithms
+// but is much less computationally intensive---it can be performed on a 3.3 V Pro Mini operating at 8 MHz!
+void MadgwickQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz)
+{
+    float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3];   // short name local variable for readability
+    float norm;
+    float hx, hy, _2bx, _2bz;
+    float s1, s2, s3, s4;
+    float qDot1, qDot2, qDot3, qDot4;
+
+    // Auxiliary variables to avoid repeated arithmetic
+    float _2q1mx;
+    float _2q1my;
+    float _2q1mz;
+    float _2q2mx;
+    float _4bx;
+    float _4bz;
+    float _2q1 = 2.0f * q1;
+    float _2q2 = 2.0f * q2;
+    float _2q3 = 2.0f * q3;
+    float _2q4 = 2.0f * q4;
+    float _2q1q3 = 2.0f * q1 * q3;
+    float _2q3q4 = 2.0f * q3 * q4;
+    float q1q1 = q1 * q1;
+    float q1q2 = q1 * q2;
+    float q1q3 = q1 * q3;
+    float q1q4 = q1 * q4;
+    float q2q2 = q2 * q2;
+    float q2q3 = q2 * q3;
+    float q2q4 = q2 * q4;
+    float q3q3 = q3 * q3;
+    float q3q4 = q3 * q4;
+    float q4q4 = q4 * q4;
+
+    // Normalise accelerometer measurement
+    norm = sqrt(ax * ax + ay * ay + az * az);
+    if (norm == 0.0f) return; // handle NaN
+    norm = 1.0f/norm;
+    ax *= norm;
+    ay *= norm;
+    az *= norm;
+
+    // Normalise magnetometer measurement
+    norm = sqrt(mx * mx + my * my + mz * mz);
+    if (norm == 0.0f) return; // handle NaN
+    norm = 1.0f/norm;
+    mx *= norm;
+    my *= norm;
+    mz *= norm;
+
+    // Reference direction of Earth's magnetic field
+    _2q1mx = 2.0f * q1 * mx;
+    _2q1my = 2.0f * q1 * my;
+    _2q1mz = 2.0f * q1 * mz;
+    _2q2mx = 2.0f * q2 * mx;
+    hx = mx * q1q1 - _2q1my * q4 + _2q1mz * q3 + mx * q2q2 + _2q2 * my * q3 + _2q2 * mz * q4 - mx * q3q3 - mx * q4q4;
+    hy = _2q1mx * q4 + my * q1q1 - _2q1mz * q2 + _2q2mx * q3 - my * q2q2 + my * q3q3 + _2q3 * mz * q4 - my * q4q4;
+    _2bx = sqrt(hx * hx + hy * hy);
+    _2bz = -_2q1mx * q3 + _2q1my * q2 + mz * q1q1 + _2q2mx * q4 - mz * q2q2 + _2q3 * my * q4 - mz * q3q3 + mz * q4q4;
+    _4bx = 2.0f * _2bx;
+    _4bz = 2.0f * _2bz;
+
+    // Gradient decent algorithm corrective step
+    s1 = -_2q3 * (2.0f * q2q4 - _2q1q3 - ax) + _2q2 * (2.0f * q1q2 + _2q3q4 - ay) - _2bz * q3 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q4 + _2bz * q2) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q3 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz);
+    s2 = _2q4 * (2.0f * q2q4 - _2q1q3 - ax) + _2q1 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q2 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + _2bz * q4 * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q3 + _2bz * q1) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q4 - _4bz * q2) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz);
+    s3 = -_2q1 * (2.0f * q2q4 - _2q1q3 - ax) + _2q4 * (2.0f * q1q2 + _2q3q4 - ay) - 4.0f * q3 * (1.0f - 2.0f * q2q2 - 2.0f * q3q3 - az) + (-_4bx * q3 - _2bz * q1) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (_2bx * q2 + _2bz * q4) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + (_2bx * q1 - _4bz * q3) * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz);
+    s4 = _2q2 * (2.0f * q2q4 - _2q1q3 - ax) + _2q3 * (2.0f * q1q2 + _2q3q4 - ay) + (-_4bx * q4 + _2bz * q2) * (_2bx * (0.5f - q3q3 - q4q4) + _2bz * (q2q4 - q1q3) - mx) + (-_2bx * q1 + _2bz * q3) * (_2bx * (q2q3 - q1q4) + _2bz * (q1q2 + q3q4) - my) + _2bx * q2 * (_2bx * (q1q3 + q2q4) + _2bz * (0.5f - q2q2 - q3q3) - mz);
+    norm = sqrt(s1 * s1 + s2 * s2 + s3 * s3 + s4 * s4);    // normalise step magnitude
+    norm = 1.0f/norm;
+    s1 *= norm;
+    s2 *= norm;
+    s3 *= norm;
+    s4 *= norm;
+
+    // Compute rate of change of quaternion
+    qDot1 = 0.5f * (-q2 * gx - q3 * gy - q4 * gz) - beta * s1;
+    qDot2 = 0.5f * (q1 * gx + q3 * gz - q4 * gy) - beta * s2;
+    qDot3 = 0.5f * (q1 * gy - q2 * gz + q4 * gx) - beta * s3;
+    qDot4 = 0.5f * (q1 * gz + q2 * gy - q3 * gx) - beta * s4;
+
+    // Integrate to yield quaternion
+    q1 += qDot1 * deltat;
+    q2 += qDot2 * deltat;
+    q3 += qDot3 * deltat;
+    q4 += qDot4 * deltat;
+    norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4);    // normalise quaternion
+    norm = 1.0f/norm;
+    q[0] = q1 * norm;
+    q[1] = q2 * norm;
+    q[2] = q3 * norm;
+    q[3] = q4 * norm;
+
+}
+
+
+
+// Similar to Madgwick scheme but uses proportional and integral filtering on the error between estimated reference vectors and
+// measured ones.
+void MahonyQuaternionUpdate(float ax, float ay, float az, float gx, float gy, float gz, float mx, float my, float mz)
+{
+    float q1 = q[0], q2 = q[1], q3 = q[2], q4 = q[3];   // short name local variable for readability
+    float norm;
+    float hx, hy, bx, bz;
+    float vx, vy, vz, wx, wy, wz;
+    float ex, ey, ez;
+    float pa, pb, pc;
+
+    // Auxiliary variables to avoid repeated arithmetic
+    float q1q1 = q1 * q1;
+    float q1q2 = q1 * q2;
+    float q1q3 = q1 * q3;
+    float q1q4 = q1 * q4;
+    float q2q2 = q2 * q2;
+    float q2q3 = q2 * q3;
+    float q2q4 = q2 * q4;
+    float q3q3 = q3 * q3;
+    float q3q4 = q3 * q4;
+    float q4q4 = q4 * q4;
+
+    // Normalise accelerometer measurement
+    norm = sqrt(ax * ax + ay * ay + az * az);
+    if (norm == 0.0f) return; // handle NaN
+    norm = 1.0f / norm;        // use reciprocal for division
+    ax *= norm;
+    ay *= norm;
+    az *= norm;
+
+    // Normalise magnetometer measurement
+    norm = sqrt(mx * mx + my * my + mz * mz);
+    if (norm == 0.0f) return; // handle NaN
+    norm = 1.0f / norm;        // use reciprocal for division
+    mx *= norm;
+    my *= norm;
+    mz *= norm;
+
+    // Reference direction of Earth's magnetic field
+    hx = 2.0f * mx * (0.5f - q3q3 - q4q4) + 2.0f * my * (q2q3 - q1q4) + 2.0f * mz * (q2q4 + q1q3);
+    hy = 2.0f * mx * (q2q3 + q1q4) + 2.0f * my * (0.5f - q2q2 - q4q4) + 2.0f * mz * (q3q4 - q1q2);
+    bx = sqrt((hx * hx) + (hy * hy));
+    bz = 2.0f * mx * (q2q4 - q1q3) + 2.0f * my * (q3q4 + q1q2) + 2.0f * mz * (0.5f - q2q2 - q3q3);
+
+    // Estimated direction of gravity and magnetic field
+    vx = 2.0f * (q2q4 - q1q3);
+    vy = 2.0f * (q1q2 + q3q4);
+    vz = q1q1 - q2q2 - q3q3 + q4q4;
+    wx = 2.0f * bx * (0.5f - q3q3 - q4q4) + 2.0f * bz * (q2q4 - q1q3);
+    wy = 2.0f * bx * (q2q3 - q1q4) + 2.0f * bz * (q1q2 + q3q4);
+    wz = 2.0f * bx * (q1q3 + q2q4) + 2.0f * bz * (0.5f - q2q2 - q3q3);
+
+    // Error is cross product between estimated direction and measured direction of gravity
+    ex = (ay * vz - az * vy) + (my * wz - mz * wy);
+    ey = (az * vx - ax * vz) + (mz * wx - mx * wz);
+    ez = (ax * vy - ay * vx) + (mx * wy - my * wx);
+    if (Ki > 0.0f) {
+        eInt[0] += ex;      // accumulate integral error
+        eInt[1] += ey;
+        eInt[2] += ez;
+    } else {
+        eInt[0] = 0.0f;     // prevent integral wind up
+        eInt[1] = 0.0f;
+        eInt[2] = 0.0f;
+    }
+
+    // Apply feedback terms
+    gx = gx + Kp * ex + Ki * eInt[0];
+    gy = gy + Kp * ey + Ki * eInt[1];
+    gz = gz + Kp * ez + Ki * eInt[2];
+
+    // Integrate rate of change of quaternion
+    pa = q2;
+    pb = q3;
+    pc = q4;
+    q1 = q1 + (-q2 * gx - q3 * gy - q4 * gz) * (0.5f * deltat);
+    q2 = pa + (q1 * gx + pb * gz - pc * gy) * (0.5f * deltat);
+    q3 = pb + (q1 * gy - pa * gz + pc * gx) * (0.5f * deltat);
+    q4 = pc + (q1 * gz + pa * gy - pb * gx) * (0.5f * deltat);
+
+    // Normalise quaternion
+    norm = sqrt(q1 * q1 + q2 * q2 + q3 * q3 + q4 * q4);
+    norm = 1.0f / norm;
+    q[0] = q1 * norm;
+    q[1] = q2 * norm;
+    q[2] = q3 * norm;
+    q[3] = q4 * norm;
+
+}

diff -r 000000000000 -r 32b177f0030e LSM9DS0_mbed.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/LSM9DS0_mbed.cpp	Sat Dec 05 16:23:36 2015 +0000
@@ -0,0 +1,427 @@
+/*
+Code by @OlimexSmart - Luca Olivieri
+This is a port from the Sparkfun library provided
+with the breakout board of the LSM9DS0.
+Visit their github for full comments:
+https://github.com/sparkfun/SparkFun_LSM9DS0_Arduino_Library/tree/V_1.0.1
+*/
+
+#include "LSM9DS0_mbed.h"
+
+LSM9DS0::LSM9DS0(PinName sdaP, PinName sclP, uint8_t gAddr, uint8_t xmAddr)
+{
+    // xmAddress and gAddress will store the 7-bit I2C address.
+    xmAddress = xmAddr;
+    gAddress = gAddr;
+
+    i2c_ = new I2C(sdaP, sclP); //This is initI2C(); in the original library
+    i2c_->frequency(400000);
+
+}
+
+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
+
+
+    // 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()
+{
+
+    gWriteByte(CTRL_REG1_G, 0x0F); // Normal mode, enable all axes
+    gWriteByte(CTRL_REG2_G, 0x00); // Normal mode, high cutoff frequency
+    gWriteByte(CTRL_REG3_G, 0x88);  //Interrupt enabled on both INT_G  and I2_DRDY
+    gWriteByte(CTRL_REG4_G, 0x00); // Set scale to 245 dps
+    gWriteByte(CTRL_REG5_G, 0x00); //Init default values
+
+}
+
+void LSM9DS0::initAccel()
+{
+    xmWriteByte(CTRL_REG0_XM, 0x00);
+    xmWriteByte(CTRL_REG1_XM, 0x57); // 50Hz data rate, x/y/z all enabled
+    xmWriteByte(CTRL_REG2_XM, 0x00); // Set scale to 2g
+    xmWriteByte(CTRL_REG3_XM, 0x04); // Accelerometer data ready on INT1_XM (0x04)
+
+}
+
+void LSM9DS0::initMag()
+{
+    xmWriteByte(CTRL_REG5_XM, 0x94); // Mag data rate - 100 Hz, enable temperature sensor
+    xmWriteByte(CTRL_REG6_XM, 0x00); // Mag scale to +/- 2GS
+    xmWriteByte(CTRL_REG7_XM, 0x00); // Continuous conversion mode
+    xmWriteByte(CTRL_REG4_XM, 0x04); // Magnetometer data ready on INT2_XM (0x08)
+    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./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_XM
+    //temperature = (((int16_t) temp[1] << 12) | temp[0] << 4 ) >> 4; // Temperature is a 12-bit signed integer
+    
+    uint8_t xlo = temp[0];
+    int16_t xhi = temp[1];
+    xhi <<= 8;
+    xhi |= xlo;
+    temperature = xhi;
+}
+
+
+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^(0x3 << 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::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::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 << 7);
+    // Then shift in our new ODR bits:
+    temp |= (abwRate << 7);
+    // And write the new register value back into CTRL_REG2_XM:
+    xmWriteByte(CTRL_REG2_XM, temp);
+}
+
+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 + 1.0) * 2.0) / 32768.0;
+}
+
+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) / 32768.0;
+}
+
+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.
+    I2CwriteByte(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.
+    return I2CwriteByte(xmAddress, subAddress, data);
+}
+
+uint8_t LSM9DS0::gReadByte(uint8_t subAddress)
+{
+    return I2CreadByte(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.
+    I2CreadBytes(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.
+    return I2CreadByte(xmAddress, subAddress);
+}
+
+void LSM9DS0::xmReadBytes(uint8_t subAddress, uint8_t * dest, uint8_t count)
+{
+    // read multiple bytes using the
+    // accelerometer-specific I2C address.
+    I2CreadBytes(xmAddress, subAddress, dest, count);
+}
+
+
+//I2C rewritten to accomodate i2cdev instead of Wire (Arduino)
+void LSM9DS0::I2CwriteByte(uint8_t address, uint8_t subAddress, uint8_t data)
+{
+    char dt[2];              // Initialize the Tx buffer
+    dt[0] = subAddress;         // Put slave register address in Tx buffer
+    dt[1] = data;               // Put data in Tx buffer
+    i2c_->write(address << 1, dt, 2); // Send the Tx buffer
+}
+
+uint8_t LSM9DS0::I2CreadByte(uint8_t address, uint8_t subAddress)
+{
+    i2c_->write(address << 1, (char*)&subAddress, 1, true);  // Send request, but keep connection alive
+    char dt = 0;
+    i2c_->read(address << 1, &dt, 1);                 // Fill Rx buffer with result
+
+    return dt;                                  // Return data read from slave register
+
+}
+
+void LSM9DS0::I2CreadBytes(uint8_t address, uint8_t subAddress, uint8_t * dest,
+                           uint8_t count)
+{
+    char sA = subAddress | 0x80;         // Send the register to be read. OR with 0x80 to indicate multi-read.
+    i2c_->write(address << 1, &sA, 1, true);      // Send the Tx buffer, but keep connection alive
+    i2c_->read(address << 1, (char*)dest, count);        // Read bytes from slave register address
+}

diff -r 000000000000 -r 32b177f0030e LSM9DS0_mbed.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/LSM9DS0_mbed.h	Sat Dec 05 16:23:36 2015 +0000
@@ -0,0 +1,493 @@
+/*
+Code by @OlimexSmart - Luca Olivieri
+This is a port from the Sparkfun library provided
+with the breakout board of the LSM9DS0.
+Visit their github for full comments:
+https://github.com/sparkfun/SparkFun_LSM9DS0_Arduino_Library/tree/V_1.0.1
+*/
+
+#ifndef _LSM9DS0_H__
+#define _LSM9DS0_H__
+
+#include "mbed.h"
+
+////////////////////////////
+// LSM9DS0 Gyro Registers //
+////////////////////////////
+#define WHO_AM_I_G          0x0F
+#define CTRL_REG1_G         0x20
+#define CTRL_REG2_G         0x21
+#define CTRL_REG3_G         0x22
+#define CTRL_REG4_G         0x23
+#define CTRL_REG5_G         0x24
+#define REFERENCE_G         0x25
+#define STATUS_REG_G        0x27
+#define OUT_X_L_G           0x28
+#define OUT_X_H_G           0x29
+#define OUT_Y_L_G           0x2A
+#define OUT_Y_H_G           0x2B
+#define OUT_Z_L_G           0x2C
+#define OUT_Z_H_G           0x2D
+#define FIFO_CTRL_REG_G     0x2E
+#define FIFO_SRC_REG_G      0x2F
+#define INT1_CFG_G          0x30
+#define INT1_SRC_G          0x31
+#define INT1_THS_XH_G       0x32
+#define INT1_THS_XL_G       0x33
+#define INT1_THS_YH_G       0x34
+#define INT1_THS_YL_G       0x35
+#define INT1_THS_ZH_G       0x36
+#define INT1_THS_ZL_G       0x37
+#define INT1_DURATION_G     0x38
+
+//////////////////////////////////////////
+// LSM9DS0 Accel/Magneto (XM) Registers //
+//////////////////////////////////////////
+#define OUT_TEMP_L_XM       0x05
+#define OUT_TEMP_H_XM       0x06
+#define STATUS_REG_M        0x07
+#define OUT_X_L_M           0x08
+#define OUT_X_H_M           0x09
+#define OUT_Y_L_M           0x0A
+#define OUT_Y_H_M           0x0B
+#define OUT_Z_L_M           0x0C
+#define OUT_Z_H_M           0x0D
+#define WHO_AM_I_XM         0x0F
+#define INT_CTRL_REG_M      0x12
+#define INT_SRC_REG_M       0x13
+#define INT_THS_L_M         0x14
+#define INT_THS_H_M         0x15
+#define OFFSET_X_L_M        0x16
+#define OFFSET_X_H_M        0x17
+#define OFFSET_Y_L_M        0x18
+#define OFFSET_Y_H_M        0x19
+#define OFFSET_Z_L_M        0x1A
+#define OFFSET_Z_H_M        0x1B
+#define REFERENCE_X         0x1C
+#define REFERENCE_Y         0x1D
+#define REFERENCE_Z         0x1E
+#define CTRL_REG0_XM        0x1F
+#define CTRL_REG1_XM        0x20
+#define CTRL_REG2_XM        0x21
+#define CTRL_REG3_XM        0x22
+#define CTRL_REG4_XM        0x23
+#define CTRL_REG5_XM        0x24
+#define CTRL_REG6_XM        0x25
+#define CTRL_REG7_XM        0x26
+#define STATUS_REG_A        0x27
+#define OUT_X_L_A           0x28
+#define OUT_X_H_A           0x29
+#define OUT_Y_L_A           0x2A
+#define OUT_Y_H_A           0x2B
+#define OUT_Z_L_A           0x2C
+#define OUT_Z_H_A           0x2D
+#define FIFO_CTRL_REG       0x2E
+#define FIFO_SRC_REG        0x2F
+#define INT_GEN_1_REG       0x30
+#define INT_GEN_1_SRC       0x31
+#define INT_GEN_1_THS       0x32
+#define INT_GEN_1_DURATION  0x33
+#define INT_GEN_2_REG       0x34
+#define INT_GEN_2_SRC       0x35
+#define INT_GEN_2_THS       0x36
+#define INT_GEN_2_DURATION  0x37
+#define CLICK_CFG           0x38
+#define CLICK_SRC           0x39
+#define CLICK_THS           0x3A
+#define TIME_LIMIT          0x3B
+#define TIME_LATENCY        0x3C
+#define TIME_WINDOW         0x3D
+#define ACT_THS             0x3E
+#define ACT_DUR             0x3F
+
+
+class LSM9DS0
+{
+public:
+    // 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,    // 10: +/- 2000 dps
+    };
+
+    // accel_scale defines all possible FSR's of the accelerometer:
+    enum accel_scale {
+        A_SCALE_2G, // 000: +/- 2g
+        A_SCALE_4G, // 001: +/- 4g
+        A_SCALE_6G, // 010: +/- 6g
+        A_SCALE_8G, // 011: +/- 8g
+        A_SCALE_16G // 100: +/- 16g
+    };
+
+    // mag_scale defines all possible FSR's of the magnetometer:
+    enum mag_scale {
+        M_SCALE_2GS,    // 00: +/- 2Gs
+        M_SCALE_4GS,    // 01: +/- 4Gs
+        M_SCALE_8GS,    // 10: +/- 8Gs
+        M_SCALE_12GS,   // 11: +/- 12Gs
+    };
+
+    // gyro_odr defines all possible data rate/bandwidth combos of the gyro:
+    enum gyro_odr {
+        // ODR (Hz) --- Cutoff
+        G_ODR_95_BW_125  = 0x0, //   95         12.5
+        G_ODR_95_BW_25   = 0x1, //   95          25
+        // 0x2 and 0x3 define the same data rate and bandwidth
+        G_ODR_190_BW_125 = 0x4, //   190        12.5
+        G_ODR_190_BW_25  = 0x5, //   190         25
+        G_ODR_190_BW_50  = 0x6, //   190         50
+        G_ODR_190_BW_70  = 0x7, //   190         70
+        G_ODR_380_BW_20  = 0x8, //   380         20
+        G_ODR_380_BW_25  = 0x9, //   380         25
+        G_ODR_380_BW_50  = 0xA, //   380         50
+        G_ODR_380_BW_100 = 0xB, //   380         100
+        G_ODR_760_BW_30  = 0xC, //   760         30
+        G_ODR_760_BW_35  = 0xD, //   760         35
+        G_ODR_760_BW_50  = 0xE, //   760         50
+        G_ODR_760_BW_100 = 0xF, //   760         100
+    };
+
+    // accel_oder defines all possible output data rates of the accelerometer:
+    enum accel_odr {
+        A_POWER_DOWN,   // Power-down mode (0x0)
+        A_ODR_3125,     // 3.125 Hz (0x1)
+        A_ODR_625,      // 6.25 Hz (0x2)
+        A_ODR_125,      // 12.5 Hz (0x3)
+        A_ODR_25,       // 25 Hz (0x4)
+        A_ODR_50,       // 50 Hz (0x5)
+        A_ODR_100,      // 100 Hz (0x6)
+        A_ODR_200,      // 200 Hz (0x7)
+        A_ODR_400,      // 400 Hz (0x8)
+        A_ODR_800,      // 800 Hz (9)
+        A_ODR_1600      // 1600 Hz (0xA)
+    };
+
+    // accel_abw defines all possible anti-aliasing filter rates of the accelerometer:
+    enum accel_abw {
+        A_ABW_773,      // 773 Hz (0x0)
+        A_ABW_194,      // 194 Hz (0x1)
+        A_ABW_362,      // 362 Hz (0x2)
+        A_ABW_50,       //  50 Hz (0x3)
+    };
+
+    // accel_oder defines all possible output data rates of the magnetometer:
+    enum mag_odr {
+        M_ODR_3125, // 3.125 Hz (0x00)
+        M_ODR_625,  // 6.25 Hz (0x01)
+        M_ODR_125,  // 12.5 Hz (0x02)
+        M_ODR_25,   // 25 Hz (0x03)
+        M_ODR_50,   // 50 (0x04)
+        M_ODR_100,  // 100 Hz (0x05)
+    };
+
+    // 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 readGyro(), readAccel(), and readMag() 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;
+    float abias[3];
+    float gbias[3];
+
+
+    // LSM9DS0 -- LSM9DS0 class constructor
+    // The constructor will set up a handful of private variables, and set the
+    // communication mode as well.
+    // Input:
+    //  - interface = Either MODE_SPI or MODE_I2C, whichever you're using
+    //              to talk to the IC.
+    //  - gAddr = If MODE_I2C, this is the I2C address of the gyroscope.
+    //              If MODE_SPI, this is the chip select pin of the gyro (CSG)
+    //  - xmAddr = If MODE_I2C, this is the I2C address of the accel/mag.
+    //              If MODE_SPI, this is the cs pin of the accel/mag (CSXM)
+    LSM9DS0(PinName sda, PinName scl, uint8_t gAddr, uint8_t xmAddr);
+
+    // begin() -- Initialize the gyro, accelerometer, and magnetometer.
+    // This will set up the scale and output rate of each sensor. It'll also
+    // "turn on" every sensor and every axis of every sensor.
+    // Input:
+    //  - gScl = The scale of the gyroscope. This should be a gyro_scale value.
+    //  - aScl = The scale of the accelerometer. Should be a accel_scale value.
+    //  - mScl = The scale of the magnetometer. Should be a mag_scale value.
+    //  - gODR = Output data rate of the gyroscope. gyro_odr value.
+    //  - aODR = Output data rate of the accelerometer. accel_odr value.
+    //  - mODR = Output data rate of the magnetometer. mag_odr value.
+    // Output: The function will return an unsigned 16-bit value. The most-sig
+    //      bytes of the output are the WHO_AM_I reading of the accel. The
+    //      least significant two bytes are the WHO_AM_I reading of the gyro.
+    // All parameters have a defaulted value, so you can call just "begin()".
+    // Default values are FSR's of: +/- 245DPS, 2g, 2Gs; ODRs of 95 Hz for
+    // gyro, 100 Hz for accelerometer, 100 Hz for magnetometer.
+    // Use the return value of this function to verify communication.
+    uint16_t begin(gyro_scale gScl = G_SCALE_245DPS,
+                   accel_scale aScl = A_SCALE_2G, mag_scale mScl = M_SCALE_2GS,
+                   gyro_odr gODR = G_ODR_95_BW_125, accel_odr aODR = A_ODR_50,
+                   mag_odr mODR = M_ODR_50);
+
+    // readGyro() -- 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 readGyro().
+    void readGyro();
+
+    // readAccel() -- 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 readAccel().
+    void readAccel();
+
+    // readMag() -- 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 readMag().
+    void readMag();
+
+    // 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 enum.
+    void setGyroScale(gyro_scale 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 enum.
+    void setAccelScale(accel_scale 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 enum.
+    void setMagScale(mag_scale mScl);
+
+    // setGyroODR() -- Set the output data rate and bandwidth of the gyroscope
+    // Input:
+    //  - gRate = The desired output rate and cutoff frequency of the gyro.
+    //      Must be a value from the gyro_odr enum (check above, there're 14).
+    void setGyroODR(gyro_odr gRate);
+
+    // setAccelODR() -- Set the output data rate of the accelerometer
+    // Input:
+    //  - aRate = The desired output rate of the accel.
+    //      Must be a value from the accel_odr enum (check above, there're 11).
+    void setAccelODR(accel_odr aRate);
+
+    // setMagODR() -- Set the output data rate of the magnetometer
+    // Input:
+    //  - mRate = The desired output rate of the mag.
+    //      Must be a value from the mag_odr enum (check above, there're 6).
+    void setMagODR(mag_odr mRate);
+
+    // setAccelABW() -- Set the anti-aliasing filter rate of the accelerometer
+    // Input:
+    //  - abwRate = The desired anti-aliasing filter rate of the accel.
+    //      Must be a value from the accel_abw enum (check above, there're 4).
+    void setAccelABW(accel_abw abwRate);
+
+
+    // configGyroInt() -- Configure the gyro interrupt output.
+    // Triggers can be set to either rising above or falling below a specified
+    // threshold. This function helps setup the interrupt configuration and
+    // threshold values for all axes.
+    // Input:
+    //  - int1Cfg = A 8-bit value that is sent directly to the INT1_CFG_G
+    //      register. This sets AND/OR and high/low interrupt gen for each axis
+    //  - int1ThsX = 16-bit interrupt threshold value for x-axis
+    //  - int1ThsY = 16-bit interrupt threshold value for y-axis
+    //  - int1ThsZ = 16-bit interrupt threshold value for z-axis
+    //  - duration = Duration an interrupt holds after triggered. This value
+    //      is copied directly into the INT1_DURATION_G register.
+    // Before using this function, read about the INT1_CFG_G register and
+    // the related INT1* registers in the LMS9DS0 datasheet.
+    void configGyroInt(uint8_t int1Cfg, uint16_t int1ThsX = 0,
+                       uint16_t int1ThsY = 0, uint16_t int1ThsZ = 0,
+                       uint8_t duration = 0);
+
+    void calLSM9DS0(float gbias[3], float abias[3]);
+
+
+private:
+    // xmAddress and gAddress store the I2C address
+    // for each sensor.
+    uint8_t xmAddress, gAddress;
+
+    // gScale, aScale, and mScale store the current scale range for each
+    // sensor. Should be updated whenever that value changes.
+    gyro_scale gScale;
+    accel_scale aScale;
+    mag_scale mScale;
+
+    // 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;
+
+    // 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 gReadByte(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 gReadBytes(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 gWriteByte(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 xmReadByte(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 xmReadBytes(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 xmWriteByte(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();
+
+
+    ///////////////////
+    // I2C Functions //
+    ///////////////////
+    I2C* i2c_;
+
+
+    // 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.
+    void I2CreadBytes(uint8_t address, uint8_t subAddress, uint8_t * dest, uint8_t count);
+};
+
+#endif // _LSM9DS0_H //

diff -r 000000000000 -r 32b177f0030e mbed.bld
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Sat Dec 05 16:23:36 2015 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/165afa46840b
\ No newline at end of file