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/******************************************************************************
SparkFunMPU9250-DMP.h - MPU-9250 Digital Motion Processor Arduino Library 
Jim Lindblom @ SparkFun Electronics
original creation date: November 23, 2016
https://github.com/sparkfun/SparkFun_MPU9250_DMP_Arduino_Library

This library implements motion processing functions of Invensense's MPU-9250.
It is based on their Emedded MotionDriver 6.12 library.
	https://www.invensense.com/developers/software-downloads/

******************************************************************************/
#ifndef _SPARKFUN_MPU9250_DMP_H_
#define _SPARKFUN_MPU9250_DMP_H_

#include <mdcompat.h>
#include <mbed.h>

// Optimally, these defines would be passed as compiler options, but Arduino
// doesn't give us a great way to do that.
#ifndef MPU9250
#define MPU9250
#endif
#define AK8963_SECONDARY
#define COMPASS_ENABLED

// Include the Invensense MPU9250 driver and DMP keys:
extern "C" {
#include "inv_mpu.h"
#include "inv_mpu_dmp_motion_driver.h"
}

typedef int inv_error_t;
#define INV_SUCCESS 0
#define INV_ERROR 0x20

enum t_axisOrder {
	X_AXIS, // 0
	Y_AXIS, // 1
	Z_AXIS  // 2
};

// Define's passed to update(), to request a specific sensor (or multiple):
#define UPDATE_ACCEL   (1<<1)
#define UPDATE_GYRO    (1<<2)
#define UPDATE_COMPASS (1<<3)
#define UPDATE_TEMP    (1<<4)

#define INT_ACTIVE_HIGH 0
#define INT_ACTIVE_LOW  1
#define INT_LATCHED     1
#define INT_50US_PULSE  0

#define MAX_DMP_SAMPLE_RATE 200 // Maximum sample rate for the DMP FIFO (200Hz)
#define FIFO_BUFFER_SIZE 512 // Max FIFO buffer size

const signed char defaultOrientation[9] = {
	1, 0, 0,
	0, 1, 0,
	0, 0, 1
};
#define ORIENT_PORTRAIT          0
#define ORIENT_LANDSCAPE         1
#define ORIENT_REVERSE_PORTRAIT  2
#define ORIENT_REVERSE_LANDSCAPE 3

class MPU9250_DMP 
{
public:
	int ax, ay, az;
	int gx, gy, gz;
	int mx, my, mz;
	long qw, qx, qy, qz;
	long temperature;
	unsigned long time;
	float pitch, roll, yaw;
	float heading;
	
	MPU9250_DMP();
	
	// begin(void) -- Verifies communication with the MPU-9250 and the AK8963,
	// and initializes them to the default state:
	// All sensors enabled
	// Gyro FSR: +/- 2000 dps
	// Accel FSR: +/- 2g
	// LPF: 42 Hz
	// FIFO: 50 Hz, disabled
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t begin(void);
	
	// setSensors(unsigned char) -- Turn on or off MPU-9250 sensors. Any of the 
	// following defines can be combined: INV_XYZ_GYRO, INV_XYZ_ACCEL, 
	// INV_XYZ_COMPASS, INV_X_GYRO, INV_Y_GYRO, or INV_Z_GYRO
	// Input: Combination of enabled sensors. Unless specified a sensor will be
	//  disabled.
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t setSensors(unsigned char sensors);
	
	// setGyroFSR(unsigned short) -- Sets the full-scale range of the gyroscope
	// Input: Gyro DPS - 250, 500, 1000, or 2000
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t setGyroFSR(unsigned short fsr);
	// getGyroFSR -- Returns the current gyroscope FSR
	// Output: Current Gyro DPS - 250, 500, 1000, or 2000
	unsigned short getGyroFSR(void);
	// getGyroSens -- Returns current gyroscope sensitivity. The FSR divided by
	// the resolution of the sensor (signed 16-bit).
	// Output: Currently set gyroscope sensitivity (e.g. 131, 65.5, 32.8, 16.4)
	float getGyroSens(void);
	
	// setAccelFSR(unsigned short) -- Sets the FSR of the accelerometer
	// 
	// Input: Accel g range - 2, 4, 8, or 16
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t setAccelFSR(unsigned char fsr);
	// getAccelFSR -- Returns the current accelerometer FSR
	// Output: Current Accel g - 2, 4, 8, or 16
	unsigned char getAccelFSR(void);
	// getAccelSens -- Returns current accelerometer sensitivity. The FSR 
	// divided by the resolution of the sensor (signed 16-bit).
	// Output: Currently set accel sensitivity (e.g. 16384, 8192, 4096, 2048)
	unsigned short getAccelSens(void);
	
	// getMagFSR -- Returns the current magnetometer FSR
	// Output: Current mag uT range - +/-1450 uT
	unsigned short getMagFSR(void);
	// getMagSens -- Returns current magnetometer sensitivity. The FSR 
	// divided by the resolution of the sensor (signed 16-bit).
	// Output: Currently set mag sensitivity (e.g. 0.15)
	float getMagSens(void);
	
	// setLPF -- Sets the digital low-pass filter of the accel and gyro.
	// Can be any of the following: 188, 98, 42, 20, 10, 5 (value in Hz)
	// Input: 188, 98, 42, 20, 10, or 5 (defaults to 5 if incorrectly set)
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t setLPF(unsigned short lpf);
	// getLPF -- Returns the set value of the LPF.
	//
	// Output: 5, 10, 20, 42, 98, or 188 if set. 0 if the LPF is disabled.
	unsigned short getLPF(void);
	
	// setSampleRate -- Set the gyroscope and accelerometer sample rate to a 
	// value between 4Hz and 1000Hz (1kHz).
	// The library will make an attempt to get as close as possible to the
	// requested sample rate.
	// Input: Value between 4 and 1000, indicating the desired sample rate
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t setSampleRate(unsigned short rate);
	// getSampleRate -- Get the currently set sample rate.
	// May differ slightly from what was set in setSampleRate.
	// Output: set sample rate of the accel/gyro. A value between 4-1000.
	unsigned short getSampleRate(void);
	
	// setCompassSampleRate -- Set the magnetometer sample rate to a value
	// between 1Hz and 100 Hz.
	// The library will make an attempt to get as close as possible to the
	// requested sample rate.
	// Input: Value between 1 and 100, indicating the desired sample rate
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t setCompassSampleRate(unsigned short rate);
	// getCompassSampleRate -- Get the currently set magnetometer sample rate.
	// May differ slightly from what was set in setCompassSampleRate.
	//
	// Output: set sample rate of the magnetometer. A value between 1-100
	unsigned short getCompassSampleRate(void);
	
	// dataReady -- checks to see if new accel/gyro data is available.
	// (New magnetometer data cannot be checked, as the library runs that sensor 
	//  in single-conversion mode.)
	// Output: true if new accel/gyro data is available
	bool dataReady();
	
	// update -- Reads latest data from the MPU-9250's data registers.
	// Sensors to be updated can be set using the [sensors] parameter.
	// [sensors] can be any combination of UPDATE_ACCEL, UPDATE_GYRO,
	// UPDATE_COMPASS, and UPDATE_TEMP.
	// Output: INV_SUCCESS (0) on success, otherwise error
	// Note: after a successful update the public sensor variables 
	// (e.g. ax, ay, az, gx, gy, gz) will be updated with new data 
	inv_error_t update(unsigned char sensors = 
	                   UPDATE_ACCEL | UPDATE_GYRO | UPDATE_COMPASS);
	
	// updateAccel, updateGyro, updateCompass, and updateTemperature are 
	// called by the update() public method. They read from their respective
	// sensor and update the class variable (e.g. ax, ay, az)
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t updateAccel(void);
	inv_error_t updateGyro(void);
	inv_error_t updateCompass(void);
	inv_error_t updateTemperature(void);
	
	// configureFifo(unsigned char) -- Initialize the FIFO, set it to read from
	// a select set of sensors.
	// Any of the following defines can be combined for the [sensors] parameter:
	// INV_XYZ_GYRO, INV_XYZ_ACCEL, INV_X_GYRO, INV_Y_GYRO, or INV_Z_GYRO
	// Input: Combination of sensors to be read into FIFO
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t configureFifo(unsigned char sensors);
	// getFifoConfig -- Returns the sensors configured to be read into the FIFO
	// Output: combination of INV_XYZ_GYRO, INV_XYZ_ACCEL, INV_Y_GYRO,
	//         INV_X_GYRO, or INV_Z_GYRO
	unsigned char getFifoConfig(void);
	// fifoAvailable -- Returns the number of bytes currently filled in the FIFO
	// Outputs: Number of bytes filled in the FIFO (up to 512)
	unsigned short fifoAvailable(void);
	// updateFifo -- Reads from the top of the FIFO, and stores the new data
	// in ax, ay, az, gx, gy, or gz (depending on how the FIFO is configured).
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t updateFifo(void);
	// resetFifo -- Resets the FIFO's read/write pointers
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t resetFifo(void);
	
	// enableInterrupt -- Configure the MPU-9250's interrupt output to indicate
	// when new data is ready.
	// Input: 0 to disable, >=1 to enable
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t enableInterrupt(unsigned char enable = 1);
	// setIntLevel -- Configure the MPU-9250's interrupt to be either active-
	// high or active-low.
	// Input: 0 for active-high, 1 for active-low
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t setIntLevel(unsigned char active_low);
	// setIntLatched -- Configure the MPU-9250's interrupt to latch or operate
	// as a 50us pulse.
	// Input: 0 for 
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t setIntLatched(unsigned char enable);
	// getIntStatus -- Reads the MPU-9250's INT_STATUS register, which can
	// indicate what (if anything) caused an interrupt (e.g. FIFO overflow or
	// or data read).
	// Output: contents of the INT_STATUS register
	short getIntStatus(void);
	
	// dmpBegin -- Initialize the DMP, enable one or more features, and set the FIFO's sample rate
	// features can be any one of 
	// DMP_FEATURE_TAP -- Tap detection
	// DMP_FEATURE_ANDROID_ORIENT -- Orientation (portrait/landscape) detection
	// DMP_FEATURE_LP_QUAT -- Accelerometer, low-power quaternion calculation
	// DMP_FEATURE_PEDOMETER -- Pedometer (always enabled)
	// DMP_FEATURE_6X_LP_QUAT -- 6-axis (accel/gyro) quaternion calculation
	// DMP_FEATURE_GYRO_CAL -- Gyroscope calibration (0's out after 8 seconds of no motion)
	// DMP_FEATURE_SEND_RAW_ACCEL -- Send raw accelerometer values to FIFO
	// DMP_FEATURE_SEND_RAW_GYRO -- Send raw gyroscope values to FIFO
	// DMP_FEATURE_SEND_CAL_GYRO -- Send calibrated gyroscop values to FIFO
	// fifoRate can be anywhere between 4 and 200Hz.
	// Input: OR'd list of features and requested FIFO sampling rate
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpBegin(unsigned short features = 0, unsigned short fifoRate = MAX_DMP_SAMPLE_RATE);
	
	// dmpLoad -- Loads the DMP with 3062-byte image memory. Must be called to begin DMP.
	// This function is called by the dmpBegin function.
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpLoad(void);
	
	// dmpGetFifoRate -- Returns the sample rate of the FIFO
	// Output: Set sample rate, in Hz, of the FIFO
	unsigned short dmpGetFifoRate(void);
	// dmpSetFiFoRate -- Sets the rate of the FIFO.
	// Input: Requested sample rate in Hz (range: 4-200)
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpSetFifoRate(unsigned short rate);
	
	// dmpUpdateFifo -- Reads from the top of the FIFO and fills accelerometer, gyroscope,
	// quaternion, and time public variables (depending on how the DMP is configured).
	// Should be called whenever an MPU interrupt is detected
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpUpdateFifo(void); 
	
	// dmpEnableFeatures -- Enable one, or multiple DMP features.
	// Input: An OR'd list of features (see dmpBegin)
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpEnableFeatures(unsigned short mask);
	// dmpGetEnabledFeatures -- Returns the OR'd list of enabled DMP features
	//
	// Output: OR'd list of DMP feature's (see dmpBegin for list)
	unsigned short dmpGetEnabledFeatures(void);
	
	// dmpSetTap -- Enable tap detection and configure threshold, tap time, and minimum tap count.
	// Inputs: x/y/zThresh - accelerometer threshold on each axis. Range: 0 to 1600. 0 disables tap
	//                       detection on that axis. Units are mg/ms.
	//         taps - minimum number of taps to create a tap event (Range: 1-4)
	//         tapTime - Minimum number of milliseconds between separate taps
	//         tapMulti - Maximum number of milliseconds combined taps
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpSetTap(unsigned short xThresh = 250, 
	                      unsigned short yThresh = 250, 
	                      unsigned short zThresh = 250,
						  unsigned char taps = 1, 
						  unsigned short tapTime = 100,
						  unsigned short tapMulti = 500);
	// tapAvailable -- Returns true if a new tap is available
	// Output: True if new tap data is available. Cleared on getTapDir or getTapCount.
	bool tapAvailable(void);
	// getTapDir -- Returns the tap direction.
	// Output: One of the following: TAP_X_UP, TAP_X_DOWN, TAP_Y_UP, TAP_Y_DOWN, TAP_Z_UP,
	//         or TAP_Z_DOWN
	unsigned char getTapDir(void);
	// getTapCount -- Returns the number of taps in the sensed direction
	// Output: Value between 1-8 indicating successive number of taps sensed.
	unsigned char getTapCount(void);

	// dmpSetOrientation -- Set orientation matrix, used for orientation sensing.
	// Use defaultOrientation matrix as an example input.
	// Input: Gyro and accel orientation in body frame (9-byte array)
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpSetOrientation(const signed char * orientationMatrix = defaultOrientation);
	// dmpGetOrientation -- Get the orientation, if any.
	// Output: If an orientation is detected, one of ORIENT_LANDSCAPE, ORIENT_PORTRAIT,
	//         ORIENT_REVERSE_LANDSCAPE, or ORIENT_REVERSE_PORTRAIT.
	unsigned char dmpGetOrientation(void);
	
	// dmpEnable3Quat -- Enable 3-axis quaternion calculation
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpEnable3Quat(void);
	
	// dmpEnable6Quat -- Enable 6-axis quaternion calculation
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpEnable6Quat(void);
	
	// dmpGetPedometerSteps -- Get number of steps in pedometer register
	// Output: Number of steps sensed
	unsigned long dmpGetPedometerSteps(void);
	// dmpSetPedometerSteps -- Set number of steps to a value
	// Input: Desired number of steps to begin incrementing from
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpSetPedometerSteps(unsigned long steps);
	// dmpGetPedometerTime -- Get number of milliseconds ellapsed over stepping
	// Output: Number of milliseconds where steps were detected
	unsigned long dmpGetPedometerTime(void);
	// dmpSetPedometerTime -- Set number time to begin incrementing step time counter from
	// Input: Desired number of milliseconds
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpSetPedometerTime(unsigned long time);
	
	// dmpSetInterruptMode --
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpSetInterruptMode(unsigned char mode);
	// dmpSetGyroBias --
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpSetGyroBias(long * bias);
	// dmpSetAccelBias -- 
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t dmpSetAccelBias(long * bias);
	
	// lowPowerAccel --
	// Output: INV_SUCCESS (0) on success, otherwise error
	inv_error_t lowPowerAccel(unsigned short rate);

	// calcAccel -- Convert 16-bit signed acceleration value to g's
	float calcAccel(int axis);
	// calcGyro -- Convert 16-bit signed gyroscope value to degree's per second
	float calcGyro(int axis);
	// calcMag -- Convert 16-bit signed magnetometer value to microtesla (uT)
	float calcMag(int axis);
	// calcQuat -- Convert Q30-format quaternion to a vector between +/- 1
	float calcQuat(long axis);
	
	// computeEulerAngles -- Compute euler angles based on most recently read qw, qx, qy, and qz
	// Input: boolean indicating whether angle results are presented in degrees or radians
	// Output: class variables roll, pitch, and yaw will be updated on exit.	
	void computeEulerAngles(bool degrees = true);
	
	// computeCompassHeading -- Compute heading based on most recently read mx, my, and mz values
	// Output: class variable heading will be updated on exit
	float computeCompassHeading(void);
	
	// selfTest -- Run gyro and accel self-test.
	// Output: Returns bit mask, 1 indicates success. A 0x7 is success on all sensors.
	//         Bit pos 0: gyro
	//         Bit pos 1: accel
	//         Bit pos 2: mag
	int selfTest(unsigned char debug = 0);
	
private:
	unsigned short _aSense;
	float _gSense, _mSense;
	
	// Convert a QN-format number to a float
	float qToFloat(long number, unsigned char q);
	unsigned short orientation_row_2_scale(const signed char *row);
};

#endif // _SPARKFUN_MPU9250_DMP_H_