File content as of revision 13:ef7a06fa11de:

//  Cloned from 'DualBLS2018_06' on 23 November 2018
#include "mbed.h"
//#include    "users/mbed_official/code/mbed-dev/file/707f6e361f3e/targets/TARGET_STM/TARGET_STM32F4/TARGET_STM32F401xE/device/stm32f401xe.h"
//#include    "stm32f401xe.h"
//#include    "stm32f411xe.h"
#include "STM3_ESC.h"
#include "BufferedSerial.h"
#include "FastPWM.h"
#include "Servo.h"
#include "brushless_motor.h"

extern  eeprom_settings     mode     ;
extern  double  rpm2mph ;
extern  BufferedSerial pc;            //  The two com ports used. There is also an unused com port, com3 setup @ 1200 baud

brushless_motor::brushless_motor    (PinName iadc, PinName pwv, PinName pwi, 
    const uint16_t * lutptr, PinName px, PinName py, PinName pz, PortName pn, int port_bit_mask, uint32_t rnum) 
    : Motor_I(iadc), maxV(pwv,PWM_PRESECALER_DEFAULT), maxI(pwi,PWM_PRESECALER_DEFAULT), H1(px), H2(py), H3(pz), OP(pn, port_bit_mask)      //  Constructor
{
    //  Constructor
    OP = 0;
    H1.mode (PullUp);   //  PullUp resistors enabled on all Hall sensor input pins
    H2.mode (PullUp);
    H3.mode (PullUp);
    H1.rise (callback(this, &brushless_motor::Hall_change));     // Attach handler to the rising interruptIn edge
    H1.fall (callback(this, &brushless_motor::Hall_change));     // Attach handler to the falling interruptIn edge
    H2.rise (callback(this, &brushless_motor::Hall_change));     // Attach handler to the rising interruptIn edge
    H2.fall (callback(this, &brushless_motor::Hall_change));     // Attach handler to the falling interruptIn edge
    H3.rise (callback(this, &brushless_motor::Hall_change));     // Attach handler to the rising interruptIn edge
    H3.fall (callback(this, &brushless_motor::Hall_change));     // Attach handler to the falling interruptIn edge
    Hall_total = 0;  //  mode can be only 0, 8, 16 or 24, lut row select for Handbrake, Forward, Reverse, or Regen Braking
    Hall_previous = 0;
    maxV.period_ticks      (MAX_PWM_TICKS + 1);  //  around 18 kHz
    maxI.period_ticks      (MAX_PWM_TICKS + 1);
    maxV.pulsewidth_ticks  (MAX_PWM_TICKS - 20);    //  Motor voltage pwm is inverted, see MCP1630 data
    maxI.pulsewidth_ticks  (MAX_PWM_TICKS / 30);    //  Motor current pwm is not inverted. Initial values for scope hanging test
    visible_mode    = MOTOR_REGENBRAKE;
    inner_mode      = MOTOR_REGENBRAKE;
    lut = lutptr;                       //  Pointer to motor energisation bit pattern table
    current_sense_rs_offset = rnum;     //  This is position in mode.rd(current_sense_rs_offset)
    Hall_index[0] = Hall_index[1]  = read_Halls    ();
    tickleon    = 0;
    direction   = 0;
    angle_cnt   = 0;        //  Incremented or decremented on each Hall event according to actual measured direction of travel
    encoder_error_cnt = 0;  //  Incremented when Hall transition not recognised as either direction
    last_V = last_I = 0.0;
    Idbl = 0.0;
    numof_current_sense_rs = 1.0;
    RPM_filter  = 0.0;
    dv_by_dt = 0.0;
    sdbl[1] = 0.25;     //  Remind me. What are these all about ?
    sdbl[2] = 9.0;
    sdbl[3] = 0.4;
    sdbl[4] = 0.2;
    dRPM        = 0.0;
    V_clamp =   1.0 ;       //  Used to limit top speed
    motor_poles   = 8;    //  Default to 8 pole motor
#ifdef  USING_DC_MOTORS
    dc_motor = (Hall_index[0] == 7) ? true : false    ;
#endif
}

/**
*   void    brushless_motor::sniff_current   ()  {          //  Initiate ADC current reading
*       This to be called in response to ticker timebase interrupt.
*       As designed, called at 200 micro second intervals (Feb 2019)
*       Updates double I.dbl current measured in milliamps
*       Reading not used elsewhere in this code but made available through command line for external controller
*/
void    brushless_motor::sniff_current   ()  {          //  Initiate ADC current reading
    const   double  sampweight  = 0.01 ; /// (double)CURRENT_SAMPLES_AVERAGED    ;
    const   double  shrinkby    = 1.0 - sampweight;
    uint16_t    samp    = Motor_I.read_u16    (); //  CHECK but thought to be called once per 200us for each motor - CORRECT Feb 2019
    double      dbls    = ((double)samp) * numof_current_sense_rs / 6.0;    //  reading in mA
    Idbl *= shrinkby;              //  Jan 2019    New recursive low pass filter
    Idbl += dbls * sampweight;     //  Current reading available, however not certain this is of any real use
}

bool    brushless_motor::poles  (int p)  {              //  Jan 2019 max_rom no longer used. target_speed is preferred
    if  (!max_rpm)  {   //  Not been set since powerup
        max_rpm = (uint32_t) (((double)mode.rd(TOP_SPEED) / rpm2mph) / 10.0)  ;
        target_speed = (double)mode.rd(TOP_SPEED) / 10.0;
        numof_current_sense_rs = (double)mode.rd(current_sense_rs_offset);
        pc.printf   ("max_rpm=%d, top speed=%.1f, rpm2mph=%.6f\r\n", max_rpm, target_speed, rpm2mph);
    }
    if  (p == 4 || p == 6 || p == 8)    {
        motor_poles = p;
        return  true;
    }
    return  false;
}

void    brushless_motor::Hall_change   ()  {
    int32_t     delta_theta;
    const   int32_t delta_theta_lut[] = {   //  Looks up -1 for forward move detected, +1 for reverse move detected, 0 for error or unknown
        0, 0, 0, 0, 0, 0, 0, 0,     //  Previous Hindex was 0
        0, 0, 0,-1, 0, 1, 0, 0,     //  Previous Hindex was 1
        0, 0, 0, 1, 0, 0,-1, 0,     //  Previous Hindex was 2
        0, 1,-1, 0, 0, 0, 0, 0,     //  Previous Hindex was 3
        0, 0, 0, 0, 0,-1, 1, 0,     //  Previous Hindex was 4
        0,-1, 0, 0, 1, 0, 0, 0,     //  Previous Hindex was 5
        0, 0, 1, 0,-1, 0, 0, 0,     //  Previous Hindex was 6
        0, 0, 0, 0, 0, 0, 0, 0,     //  Previous Hindex was 7
    }  ;

    Hall_index[0]   = read_Halls    ();
    delta_theta = delta_theta_lut[(Hall_index[1] << 3) | Hall_index[0]];

    if  (delta_theta == 0)
        encoder_error_cnt++;
    else
        angle_cnt += delta_theta;
    OP = lut[inner_mode | Hall_index[0]];  //  changed mode to inner_mode 27/04/18
    Hall_total++;
    Hall_index[1] = Hall_index[0];
}

/**
*   void    brushless_motor::direction_set   (int dir)  {
*   Used to set direction according to mode data from eeprom
*/
void    brushless_motor::direction_set   (int dir)
{
    direction = (dir != 0) ? MOTOR_FORWARD | MOTOR_REVERSE : 0; //  bits used in eor, FORWARD = 1<<3, REVERSE = 1<<4
}

int     brushless_motor::read_Halls  ()
{
    int x = 0;
    if  (H1)    x |= 1;
    if  (H2)    x |= 2;
    if  (H3)    x |= 4;
    return  x;
}

void    brushless_motor::high_side_off   () //  Jan 2019    Only ever called from main when high side gate drive charge might need pumping up
{
    uint16_t    p = OP;
    p &= lut[32];   //  KEEP_L_MASK_A or B
    OP = p;
}
/*
void    brushless_motor::low_side_on   ()
{
    maxV.pulsewidth_ticks  (1);
    OP = lut[31];   //  KEEP_L_MASK_A or B
}
*/

void    brushless_motor::set_speed (double p) //  Sets target_speed
{
    target_speed = p;
}


extern  double  Current_Scaler_Sep_2019;
extern  int WatchDog;
#define DRIVING (visible_mode == MOTOR_FORWARD || visible_mode == MOTOR_REVERSE)
#define ESTOP   (WatchDog == 0 && DRIVING)

/**
*   void    brushless_motor::set_V_limit (double p)  //  Sets max motor voltage.
*
*   Set motor voltage limit from zero (p=0.0) to max link voltage (p=1.0)
*/
void    brushless_motor::set_V_limit (double p)  //  Sets max motor voltage.
{
    if  (p < 0.0 || ESTOP)
        p = 0.0;
    if  (p > 1.0)
        p = 1.0;
    last_V = p;     //  Retains last voltage limit demanded by driver
    
    if  ((V_clamp < last_V) && DRIVING)    //  Jan 2019 limit top speed when driving
        p = V_clamp;    //  If motor runnable, set voltage limit to lower of last_V and V_clamp

    p *= 0.95;      //  need limit, ffi see MCP1630 data
    p   = 1.0 - p;  //  because pwm is wrong way up
    maxV.pulsewidth_ticks  ((int)(p * MAX_PWM_TICKS));  //  PWM output to MCP1630 inverted motor pwm as MCP1630 inverts
}


/**void    brushless_motor::set_I_limit (double p)     //  Sets max motor current. pwm integrated to dc ref voltage level
*
*   Set motor current limit from zero (p=0.0) to max determined by current sense resistors (p=1.0)
*       Value sent to pwm with RC integrator acting as AnalogOut.
*       pwm capable of 0.0 <= V_out <= 3.3. This feeds MCP1630 V_Ref, range 0 to 2.7v
*       Therefore (2.7/3.3) = 0.82 factor included.
*   Jan 2019 - As yet uncalibrated, so let's have a go at working it out!
*       Voltage ax current sense resistors amplified by op-amp with gain 5.7 (see EasyPC file 'BrushlessSTM3.sch', U6, R63, R64)
*       This then put through pot divider (10k with 4k7 to ground, gain 0.32) reducing overall gain to 1.8 (accurate enough)
*       This connects to MCP1630 CS (current sense) pin which works over the voltage range 0.0 to 0.9v
*       Therefore 0.5v across current sense resistor is sufficient to turn driver off.
*       0.5v across 0.05 ohm gives 10A per current sense resistor fitted.
*       ** NOTE ** This is fast acting cycle by cycle current limit, the 10A figure is therefore peak T_on current.
*
*   Current flows through current sense reaistor when one high side and one low side switch are on, expect a rising ramp due to motor inductance.
*   When either switch is off, inductor current continues to flow but not through current sense resistors, through a parasitic diode instead.
*   Thus T_on current is measured, T_off current is not measured
*   This means current reading should approximate to current taken from the supply. Motor average current may be considerably higher.
*       During REGEN_BRAKING, current flows the 'wrong' way through sense resistors and can not be measured.
*
*   Board designed to have 1, 2, 3 or 4 0R05 current sense resistors per motor for 10A, 20A, 30A or 40A peak motor currents
*/

void    brushless_motor::set_I_limit (double p)     //  Sets max motor current. pwm integrated to dc ref voltage level
{
    const   uint32_t MPR = ((MAX_PWM_TICKS * 9) / 11);    //  Scales 3.3v pwm DAC output to 2.7v V_Ref input
    if  (p < 0.0 || ESTOP)
        p = 0.0;
    if  (p > 1.0)
        p = 1.0;
    last_I = p;     //  Retains last current limit demanded by driver
    if  (DRIVING)    {
        if  (Current_Scaler_Sep_2019 > 1.0)
            Current_Scaler_Sep_2019 = 1.0;
        if  (Current_Scaler_Sep_2019 < 0.0)
            Current_Scaler_Sep_2019 = 0.0;
        p *= Current_Scaler_Sep_2019;
    }
    maxI.pulsewidth_ticks  ((uint32_t)(p * MPR));  //  PWM
}


/**
*   void    brushless_motor::speed_monitor_and_control   ()       //  ** CALL THIS 32 TIMES PER SECOND **
*   Call this once per 'MAIN_LOOP_REPEAT_TIME_US= 31250' main loop pass to keep RPM and MPH figures correct
*   Tracks total transitions on Hall sensor inputs to determine speed.
*   Sets variables double dRPM of motor RPM, and double dMPH miles per hour
*
*   Speed control - double target_speed as reference input. *
*       **  This is where any speed limit gets applied **
*           Motor voltage reduced when at or over speed. Does NOT apply any braking
*   Scope for further improvement of control algorithm - crude implementation of PID with no I
*/
void    brushless_motor::speed_monitor_and_control   ()       //  call this once per 'MAIN_LOOP_REPEAT_TIME_US= 31250' main loop pass to keep count = edges per sec
{
#ifdef  USING_DC_MOTORS
    if  (dc_motor)
        return  0;
#endif
//  Feb 2019 - coefficients currently values in ram to allow for tweaking via command line. Will be 'const' once settled upon.
//    const   double  samp_scale  = 0.35;                  //  Tweak this value only to tune filter
    double  samp_scale  = sdbl[1];                  //  Tweak this value only to tune filter
    double  shrink_by   = 1.0 - samp_scale;
//    const   double  dv_scale    =   0.15;
    double  dv_scale    =   sdbl[3];
    double  dv_shrink   = 1.0 - dv_scale;
    double  speed_error, d, t;
    uint32_t        Hall_tot_copy = Hall_total;     //  Copy value for use throughout function as may get changed at any instant during exec !
    moving_flag  = true;
    if  (Hall_previous == Hall_tot_copy)  {         //  Test for motor turning or not
        moving_flag  = false;                       //  Zero Hall transitions since previous call - motor not moving
        tickleon    = TICKLE_TIMES;                 //  May need to tickle some charge into high side switch bootstrap supplies
    } 
    d   = (double) ((Hall_tot_copy - Hall_previous) *640);  //  (Motor Hall sensor transitions in previous 31250us) * 640
    d   /= motor_poles;                 //  d now true but lumpy 'RPM' during most recent 31250us corrected for number of motor poles
    t   = RPM_filter;   //  Value from last time around
    RPM_filter  *= shrink_by;
    RPM_filter  += (d * samp_scale);  //  filtered RPM
                                        //  RPM_filter[n] = shrink_by RPM_filter[n - 1] + samp_scale x[n]
    t    -= RPM_filter;  //  more like minus dv/dt
    dv_by_dt    *= dv_shrink;
    dv_by_dt    += (t * dv_scale);    //  filtered rate of change, the 'D' Differential contribution to PID control
    dRPM += RPM_filter;
    dRPM /= 2.0;
    dMPH    = RPM_filter * rpm2mph;     //  Completed updates of RPM and MPH
    
    if  (inner_mode == MOTOR_FORWARD || inner_mode == MOTOR_REVERSE) {  //  Speed control only makes sense when motor runnable
        speed_error    = (target_speed - dMPH) / 1000.0;                //  'P' Proportional contribution to PID control
        d = V_clamp + (speed_error * sdbl[2]) + ((dv_by_dt / 1000.0) * sdbl[4]);  //  Apply P+I+D (with I=0) control
        if  (d > 1.0)   d = 1.0;
        if  (d < 0.0)   d = 0.0;
        V_clamp = d;
        if  (V_clamp < last_V)   //  Jan 2019 limit top speed when driving
        {    
            d *= 0.95;   //  need limit, ffi see MCP1630 data
            d   = 1.0 - d;  //  because pwm is wrong way up
            maxV.pulsewidth_ticks  ((int)(d * MAX_PWM_TICKS));  //  PWM output to MCP1630 inverted motor pwm as MCP1630 inverts
        }
    }
/*    temp_tick++;
    if  (temp_tick > 35)    {   //  one and a bit second
        temp_tick = 0;
        pc.printf   ("RPM %.0f, %.3f, %.3f, %.2f, dv/dt%.3f\r\n", dRPM, RPM_filter, d, dMPH, dv_by_dt);
    }
*/
    Hall_previous = Hall_tot_copy;
}

bool    brushless_motor::is_moving ()
{
    return  moving_flag;
}

/**
bool    brushless_motor::set_mode (int m)
Use to set motor to one mode of HANDBRAKE, FORWARD, REVERSE, REGENBRAKE.
If this causes change of mode, also sets V and I to zero.
*/
bool    brushless_motor::set_mode (int m)
{
    if  ((m != MOTOR_HANDBRAKE) && (m != MOTOR_FORWARD) && (m != MOTOR_REVERSE) && (m != MOTOR_REGENBRAKE))  {
//        pc.printf   ("Error in set_mode, invalid mode %d\r\n", m);
        return  false;
    }
    if  (visible_mode != m) {   //  Mode change, kill volts and amps to be safe
        set_V_limit (0.0);
        set_I_limit (0.0);
        visible_mode = m;
    }
    if  (m == MOTOR_FORWARD || m == MOTOR_REVERSE)
        m ^= direction;
    inner_mode = m;     //  idea is to use inner_mode only in lut addressing, keep 'visible_mode' true regardless of setup data in eeprom
    return  true;
}

void    brushless_motor::motor_set  ()  //  Energise Port with data determined by Hall sensors
{
    Hall_index[0]  = read_Halls    ();
    OP = lut[inner_mode | Hall_index[0]];
}