File content as of revision 0:9621bbc04b9b:

//=====================================================================================================
// Mag_track.h
//=====================================================================================================
//
// Implementation of Magnetic tracking algorithm.
//
// Date         Author          Notes
// 30/01/2020   DAFG            Initial release
//
//=====================================================================================================
#ifndef Mag_track_h
#define Mag_track_h
//----------------------------------------------------------------------------------------------------
// Variable declaration

    // maximum number of inputs that can be handled
    // in one function call
    #define MAX_INPUT_LEN   16
    // maximum length of filter than can be handled
    #define MAX_FLT_LEN     84
    // buffer to hold all of the input samples
    #define BUFFER_LEN      (MAX_FLT_LEN + MAX_INPUT_LEN)
    extern int16_t lp_insamp[ 3*BUFFER_LEN ]; // Array to hold input samples LP
    #define FILTER_LEN_LP 82
    // fs = 800 Hz; low pass fc 10-35 Hz
    extern int16_t coeffs_lp[FILTER_LEN_LP];
    extern int16_t insamp[ 3*BUFFER_LEN ];    // Array to hold input samples BP
    #define FILTER_LEN_BP  71        
    // fs = 800 Hz; Band pass 85-115 Hz
    extern int16_t coeffs_bp[ FILTER_LEN_BP ];
    
    extern Serial PC;
    extern DigitalOut myled;

//---------------------------------------------------------------------------------------------------
// Function declarations

    /////// FIR init
    void firFixedInit( void );
    /////// the FIR filter function
    void firFixed( int16_t *coeffs, int16_t *input, int16_t *output,
            int length, int filterLength, int bias, int16_t *buffer );
    /////// SIGN FUNCTION
    int sign(int16_t x);
    /////// QUATERNION product FUNCTION
    void Qprod(float *p, float *q, float *r );
    /////// QUATERNION rotation FUNCTION
    void Qrotate(float *v, float *q, float *out );
    /////// Sensor set_up function
    void sensor_setup();
    /////// MPU sensor axes alignment and offset correction 
    void MPUrot_offset(int16_t *Data, char *rawData, int16_t *offset);
    /////// Magnetic sensor offset correction
    void Mag_offset(int16_t *M_read, char *data, int16_t *offset);
    /////// Sensors reading
    void Read_Mag(int16_t *M_read);
    void Read_Acc(int16_t *A_read);
    void Read_Gyr(int16_t *G_read);
    /////// Madgwick Quaternion update high-level function
    void QUpdate(int32_t *q, float *m, float *a, float *g, int16_t *Mag, int16_t *Acc, int16_t *Gyr, float *Q_init, int32_t *Q_out);
    /////// Filtered magnetic signals envelope extraction 
    void Env_extraction(int16_t *E, int16_t *buffer_rot, int16_t *max, int16_t *p_i, double *R, double *ph, int16_t *S);
#endif
//=====================================================================================================
// End of file
//=====================================================================================================