File content as of revision 13:ef7a06fa11de:

/*
    STM3_ESC    Electronic Speed Controller board, drives Two Brushless Motors, full Four Quadrant Control.
    Jon Freeman  B. Eng Hons
    2015 - 2019
*/
#include "mbed.h"
#include "STM3_ESC.h"
#include "BufferedSerial.h"
#include "FastPWM.h"
#include "Servo.h"
#include "brushless_motor.h"
#include "Radio_Control_In.h"
//#ifdef  TARGET_NUCLEO_F401RE    //

//#endif
/*
Brushless_STM3_ESC board
Jan 2019    *   WatchDog implemented. Default is disabled, 'kd' command from TS controller enables and reloads
            *   Tidied brushless_motor class, parameter passing now done properly
            *   class   RControl_In created. Inputs now routed to new pins, can now use two chans both class   RControl_In and Servo out
                (buggery board required for new inputs on June 2018 issue boards)
            *   Added version string
            *   Error handler written and included
            *   Realised Nanotec motors are 6 pole, all others are 8 pole. Modified 'mode' to include 'motor poles' in EEPROM data, now speed reading correct for all
            *   Reorganised EEPROM data - mode setting now much easier, less error prone
            *   Maximum speed now one EEPROM option, range 1.0 to 25.0 MPH in 0.1 MPH steps
                
New 29th May 2018 **
                LMT01 temperature sensor routed to T1 - and rerouted to PC_13 as InterruptIn on T1 (ports A and B I think) not workable
        March 2019 temp sensor only included with TEMP_SENSOR_ENABLE defined. Temp reading not essential, LMT01 was not a good choice due to
        significant loading of interrupts, threatening integrity of Real Time System
*/


/*  STM32F401RE - compile using NUCLEO-F401RE
//  PROJECT -   STM3_ESC Dual Brushless Motor Controller -   Jon Freeman     June 2018.

AnalogIn to read each motor current

____________________________________________________________________________________
        CONTROL PHILOSOPHY
This STM3_ESC Bogie drive board software should ensure sensible control when commands supplied are not sensible !

That is, smooth transition between Drive, Coast and Brake to be implemented here.
The remote controller must not be relied upon to deliver sensible command sequences.

So much the better if the remote controller does issue sensible commands, but ...

____________________________________________________________________________________


*/

#if defined (TARGET_NUCLEO_F401RE)  //  CPU in 64 pin LQFP
#include    "F401RE.h"  //  See here for warnings about Servo InterruptIn not working
#endif
#if defined (TARGET_NUCLEO_F411RE)  //  CPU in 64 pin LQFP
#include    "F411RE.h"  //  See here for warnings about Servo InterruptIn not working
#endif
#if defined (TARGET_NUCLEO_F446ZE)  //  CPU in 144 pin LQFP
#include    "F446ZE.h"              //  A thought for future version
#endif
/*  Global variable declarations */
char   const_version_string[] = {"1.0.y2019.m09.d29\0"};  //  Version string, readable from serial ports
volatile    uint32_t    fast_sys_timer      = 0;    //  gets incremented by our Ticker ISR every VOLTAGE_READ_INTERVAL_US
//int         WatchDog    = WATCHDOG_RELOAD + 80; //  Allow extra few seconds at powerup
int         WatchDog    = 0; //  Set this up in main once pre-flight checks done. Allow extra few seconds at powerup
bool        WatchDogEnable  = false;    //  Must recieve explicit instruction from pc or controller to enable
uint32_t    volt_reading        = 0,    //  Global updated by interrupt driven read of Battery Volts
            driverpot_reading   = 0,    //  Global updated by interrupt driven read of Drivers Pot
            sys_timer           = 0,    //  gets incremented by our Ticker ISR every MAIN_LOOP_REPEAT_TIME_US, 31250us at Sept 2019
            AtoD_Semaphore      = 0;

bool        loop_flag   = false;        //  made true in ISR_loop_timer, picked up and made false again in main programme loop
bool        flag_8Hz    = false;        //  As loop_flag but repeats 8 times per sec
bool        temp_sensor_exists = false;
double      rpm2mph;

double      Current_Scaler_Sep_2019 = 1.0;  //  New idea - Sept 2019. Plan is to scale down motor current limit when voltage lower than nom.
                                            //  See schematic for full details, but cycle-by-cycle current limit has the effect of allowing larger average I
                                            //  at lower voltages. This is simply because current takes longer to build in motor inductance when voltage
                                            //  is low. Conversely, at high supply voltages, motor current reaches limit quickly, cutting drive, meaning
                                            //  similar current flows for shorter times at higher voltages.

#ifdef  TEMP_SENSOR_ENABLE
uint32_t    temp_sensor_count = 0,  //  incremented by every rising edge from LMT01
            last_temperature_count = 0;  //  global updated approx every 100ms after each LMT01 conversion completes
#endif
/*  End of Global variable declarations */

Ticker  tick_vread;     //  Device to cause periodic interrupts, used to time voltage readings etc
Ticker  loop_timer;     //  Device to cause periodic interrupts, used to sync iterations of main programme loop
#ifdef  TEMP_SENSOR_ENABLE
Ticker  temperature_find_ticker;
Timer   temperature_timer;
#endif
#ifdef USING_DC_MOTORS
Timer   dc_motor_kicker_timer;
Timeout motors_restore;
#endif

RControl_In     RC_chan_1   (PC_14);
RControl_In     RC_chan_2   (PC_15);   //  Instantiate two radio control input channels and specify which InterruptIn pin
error_handling_Jan_2019     ESC_Error    ;         //  Provides array usable to store error codes.

eeprom_settings     mode    (SDA_PIN, SCL_PIN)  ;   //  This MUST come before Motors setup

//uint32_t    HAtot = 0, HBtot = 0, A_Offset = 0, B_Offset = 0;
/*
    5   1   3   2   6   4  SENSOR SEQUENCE

1   1   1   1   0   0   0  ---___---___ Hall1
2   0   0   1   1   1   0  __---___---_ Hall2
4   1   0   0   0   1   1  -___---___-- Hall3

    UV  WV  WU  VU  VW  UW  OUTPUT SEQUENCE

8th July 2018
Added drive to DC brushed motors.
Connect U and W to dc motor, leave V open.

Hall codes 0 and 7 not used for brushless motors. Without Hall sensors connected pullup resistors give code 7. Use this for dc motors

*/
const   uint16_t    A_tabl[] = {  //  Origial table
    0,  0,  0,  0,  0,  0,  0,  0,  //  Handbrake
    0,  AWHVL,AVHUL,AWHUL,AUHWL,AUHVL,AVHWL,AUHWL,  //  Forward 0, WV1, VU1, WU1, UW1, UV1, VW1, 0,    //  JP, FR, SG, PWM = 1 0 1 1   Forward1
    0,  AVHWL,AUHVL,AUHWL,AWHUL,AVHUL,AWHVL,AWHUL,  //  Reverse 0, VW1, UV1, UW1, WU1, VU1, WV1, 0,    //  JP, FR, SG, PWM = 1 1 0 1   Reverse1
    0,  BRA,BRA,BRA,BRA,BRA,BRA,BRA,   //  Regenerative Braking
    KEEP_L_MASK_A, KEEP_H_MASK_A   //  [32 and 33]
}   ;

const   uint16_t    B_tabl[] = {
    0,  0,  0,  0,  0,  0,  0,  0,  //  Handbrake
    0,  BWHVL,BVHUL,BWHUL,BUHWL,BUHVL,BVHWL,BUHWL,  //  Forward 0, WV1, VU1, WU1, UW1, UV1, VW1, 0,    //  JP, FR, SG, PWM = 1 0 1 1   Forward1
    0,  BVHWL,BUHVL,BUHWL,BWHUL,BVHUL,BWHVL,BWHUL,  //  Reverse 0, VW1, UV1, UW1, WU1, VU1, WV1, 0,    //  JP, FR, SG, PWM = 1 1 0 1   Reverse1
    0,  BRB,BRB,BRB,BRB,BRB,BRB,BRB,   //  Regenerative Braking
    KEEP_L_MASK_B, KEEP_H_MASK_B
}   ;

brushless_motor   MotorA  (MOT_A_I_ADC, APWMV, APWMI, A_tabl, _MAH1, _MAH2, _MAH3, PortA, PORT_A_MASK, ISHUNTA);
brushless_motor   MotorB  (MOT_B_I_ADC, BPWMV, BPWMI, B_tabl, _MBH1, _MBH2, _MBH3, PortB, PORT_B_MASK, ISHUNTB);


extern  cli_2019    pcc, tsc;   //  command line interpreters from pc and touch screen

//  Interrupt Service Routines
#ifdef  TEMP_SENSOR_ENABLE
void    ISR_temperature_find_ticker ()      //  every 960 us, i.e. slightly faster than once per milli sec
{
    static  bool    readflag = false;
    int t = temperature_timer.read_ms   ();
    if  ((t == 5) && (!readflag))    {
        last_temperature_count = temp_sensor_count;
        temp_sensor_count = 0;
        readflag = true;
    }
    if  (t == 6)
        readflag = false;
}
#endif
/** void    ISR_loop_timer  ()
*   This ISR responds to Ticker interrupts at a rate of (probably) 32 times per second (check from constant declarations above)
*   This ISR sets global flag 'loop_flag' used to synchronise passes around main programme control loop.
*   Increments global 'sys_timer', usable anywhere as general measure of elapsed time
*/
void    ISR_loop_timer  ()      //  This is Ticker Interrupt Service Routine - loop timer - MAIN_LOOP_REPEAT_TIME_US
{
    loop_flag = true;   //  set flag to allow main programme loop to proceed
    sys_timer++;        //  Just a handy measure of elapsed time for anything to use
    if  ((sys_timer & 0x03) == 0)
        flag_8Hz    = true;
}

/** void    ISR_voltage_reader  ()
*   This ISR responds to Ticker interrupts every 'VOLTAGE_READ_INTERVAL_US' micro seconds
*
*   AtoD_reader() called from convenient point in code to take readings outside of ISRs
*/
void    ISR_voltage_reader  ()      //  This is Ticker Interrupt Service Routine ; few us between readings ; VOLTAGE_READ_INTERVAL_US    = 50
{
    AtoD_Semaphore++;
    fast_sys_timer++;        //  Just a handy measure of elapsed time for anything to use
}

#ifdef  TEMP_SENSOR_ENABLE
void    temp_sensor_isr ()      //  got rising edge from LMT01. ALMOST CERTAIN this misses some
{
    int t = temperature_timer.read_us   (); //  Must be being overrun by something, most likely culprit A-D reading ?
    temperature_timer.reset ();
    temp_sensor_count++;
    if  (t > 18)            //  Yes proved some interrupts get missed, this fixes temperature reading
        temp_sensor_count++;
//    T2 = !T2;   //  scope hanger
}
#endif
//  End of Interrupt Service Routines


void    setVI   (double v, double i)
{
    MotorA.set_V_limit  (v);  //  Sets max motor voltage
    MotorA.set_I_limit  (i);  //  Sets max motor current
    MotorB.set_V_limit  (v);
    MotorB.set_I_limit  (i);
}


/**
*   void    AtoD_reader ()  //  Call to here every VOLTAGE_READ_INTERVAL_US    = 50 once loop responds to flag set in isr
*   Not part of ISR
*/
void    AtoD_reader ()  //  Call to here every VOLTAGE_READ_INTERVAL_US    = 50 once loop responds to flag set in isr
{
    static uint32_t i = 0;
    if  (MotorA.tickleon)
        MotorA.high_side_off    ();
    if  (MotorB.tickleon)
        MotorB.high_side_off    ();
    if  (AtoD_Semaphore > 20)   {
        pc.printf   ("WARNING - sema cnt %d\r\n", AtoD_Semaphore);
        AtoD_Semaphore = 20;
    }
    while   (AtoD_Semaphore > 0)    {
        AtoD_Semaphore--;
        //  Code here to sequence through reading voltmeter, demand pot, ammeters
        switch  (i) {   //
            case    0:
                volt_reading += Ain_SystemVolts.read_u16    ();     //  Result = Result + New Reading
                volt_reading >>= 1;                                 //  Result = Result / 2
                break;                                              //  i.e. Very simple digital low pass filter
            case    1:
                driverpot_reading += Ain_DriverPot.read_u16    ();
                driverpot_reading >>= 1;
                break;
            case    2:
                MotorA.sniff_current    (); //  Initiate ADC current reading
                break;
            case    3:
                MotorB.sniff_current    ();
                break;
        }
        i++;    //  prepare to read the next input in response to the next interrupt
        if  (i > 3)
            i = 0;
    }   //  end of while (AtoD_Semaphore > 0)    {
    if  (MotorA.tickleon)   {
        MotorA.tickleon--;
        MotorA.motor_set    (); //  Reactivate any high side switches turned off above
    }
    if  (MotorB.tickleon)   {
        MotorB.tickleon--;
        MotorB.motor_set    ();
    }
}

/** double  Read_Servo1_In  ()
*   driverpot_reading is a global 16 bit unsigned int updated in interrupt service routine
*   ISR also filters signal
*   This function returns normalised double (range 0.0 to 1.0) representation of driver pot position
*/
double  Read_Servo1_In  ()
{
    const double    xjoin   = 0.5,
                    yjoin   = 0.35,
                    slope_a = yjoin / xjoin,
                    slope_b = (1.0 - yjoin)/(1.0 - xjoin);
//                    centre = 0.35,  //  For pot, first (1/3)ish in braking area, position = 1/3 drift, > (1/3)ish drive
//                    halfish = 0.5;  //  RC stick in the centre value
                    //  Bottom half of RC stick movement maps to lowest (1/3)ish pot movement
                    //  Higher half of RC stick movement maps to highest (2/3)ish pot movement
    double  t;
    double  demand = RC_chan_1.normalised();
    //  apply demand = 1.0 - demand here to swap stick move polarity
//    return  pow (demand, SERVOIN_PWR_BENDER);
    if  (demand < 0.0)  demand = 0.0;
    if  (demand > 1.0)  demand = 1.0;
    if  (demand < xjoin) {
        demand *= slope_a;
    }
    else    {
        t = yjoin + ((demand - xjoin) * slope_b);
        demand = t;
    }
    return  demand;
}

/** double  Read_DriverPot  ()
*   driverpot_reading is a global 16 bit unsigned int updated in interrupt service routine
*   ISR also filters signal by returning average of most recent two readings
*   This function returns normalised double (range 0.0 to 1.0) representation of driver pot position
*/
double  Read_DriverPot  ()
{
    return ((double) driverpot_reading) / 65536.0;     //  Normalise 0.0 <= control pot <= 1.0
}

double  Read_BatteryVolts   ()
{
    return  ((double) volt_reading) / 951.0;    //  divisor fiddled to make voltage reading correct !
}


void    Update_Current_Scaler   ()  {       //  ***NEW Sept 2019*** Called at 8Hz
const   double  Vnom = 48.0,
                Vmin = Vnom / 3.0,
                Voff = Vnom / 4.0;
                
    double  v = Read_BatteryVolts   ();
    if  (v > Vnom)
        v = Vnom;
    if  (v < Voff)
        v = Voff;
    if  (v > Vmin)  {   //  In expected normal operating voltage range
        Current_Scaler_Sep_2019 = v / Vnom;         //  May need to revisit law
    }
    else    {   //  In very low voltage region
        Current_Scaler_Sep_2019 = 0.5 * (v / Vnom);
    }
}

void    mode_set_both_motors   (int mode, double val)      //  called from cli to set fw, re, rb, hb
{
    MotorA.set_mode (mode);
    MotorB.set_mode (mode);
    if  (mode == MOTOR_REGENBRAKE)    {
        if  (val > 1.0)
            val = 1.0;
        if  (val < 0.0)
            val = 0.0;
        val *= 0.9;    //  set upper limit, this is essential
        val = sqrt  (val);  //  to linearise effect
        setVI  (val, 1.0);
    }
}



#ifdef  USING_DC_MOTORS
void    restorer    ()
{
    motors_restore.detach   ();
    if  (MotorA.dc_motor)   {
        MotorA.set_V_limit  (MotorA.last_V);
        MotorA.set_I_limit  (MotorA.last_I);
        MotorA.motor_set    ();
    }
    if  (MotorB.dc_motor)   {
        MotorB.set_V_limit  (MotorB.last_V);
        MotorB.set_I_limit  (MotorB.last_I);
        MotorB.motor_set    ();
    }
}
#endif

void    rcin_report ()  {
    double c1 = RC_chan_1.normalised();
    double c2 = RC_chan_2.normalised();
    uint32_t    pc1 = RC_chan_1.pulsecount();
    uint32_t    pc2 = RC_chan_2.pulsecount();
    pc.printf   ("At rcin_report, Ch1=%.3f, Ch2=%.3f, cnt1 %d, cnt2 %d\r\n", c1, c2, pc1, pc2);
//    if  (c1 < -0.0001)
        pc.printf   ("\t1 period %d, pulsewidth %d\r\n", RC_chan_1.period(), RC_chan_1.pulsewidth());
//    if  (c2 < -0.0001)
        pc.printf   ("\t2 period %d, pulsewidth %d\r\n", RC_chan_2.period(), RC_chan_2.pulsewidth());
}

bool    worth_the_bother    (double a, double b)    {   //  Tests size of change. No point updating tiny demand changes
    double c = a - b;
    if  (c < 0.0)
        c = 0.0 - c;
    if  (c > 0.02)
        return  true;
    return  false;
}

void    hand_control_state_machine  (int source)  {     //  if hand control mode '3', get here @ approx 30Hz to read drivers control pot
                                                        //  if servo1 mode '4', reads input from servo1 instead
enum    {   //  states used in hand_control_state_machine()
        HAND_CONT_IDLE,
        HAND_CONT_BRAKE_WAIT,
        HAND_CONT_BRAKE_POT,
        HAND_CONT_STATE_INTO_BRAKING,
        HAND_CONT_STATE_BRAKING,
        HAND_CONT_STATE_INTO_DRIVING,
        HAND_CONT_STATE_DRIVING
        }  ;

    static  int hand_controller_state = HAND_CONT_IDLE;
//    static  int old_hand_controller_direction = T5;              //  Nov 2018 reworked thanks to feedback from Rob and Quentin
    static  double  brake_effort, drive_effort, pot_position, old_pot_position = 0.0;
    static  int dirbuf[5] = {100,100,100,100,100};      //  Initialised with invalid direction such that 'change' is read from switch
    static  int dirbufptr = 0, direction_old = -1, direction_new = -1;
    const   int buflen = sizeof(dirbuf) / sizeof(int);
    const   double      Pot_Brake_Range = 0.35;  //pow   (0.5, SERVOIN_PWR_BENDER); //0.353553 for SERVOIN_PWR_BENDER = 1.5;

   direction_old = direction_new;

//      Test for change in direction switch setting.
//      If whole buffer NEWLY filled with all Fwd or all Rev, state = brake_wait
    int diracc = 0;    
    if  (dirbufptr >= buflen)
        dirbufptr = 0;
    dirbuf[dirbufptr++] = T5;   //  Read direction switch into circular debounce buffer
    for (int i = 0; i < buflen; i++)
        diracc += dirbuf[i];    //  will = 0 or buflen if direction switch stable
    if  (diracc == buflen || diracc == 0)   //  if was all 0 or all 1
        direction_new = diracc / buflen;
    if  (direction_new != direction_old)
        hand_controller_state = HAND_CONT_BRAKE_WAIT;   //  validated change of direction switch

    switch  (source)    {
        case    3:  //  driver pot is control input
            pot_position = Read_DriverPot   ();     //  Only place read in the loop, rteads normalised 0.0 to 1.0
            break;
        case    4:  //  servo 1 input is control input
            break;
        default:
            pot_position = 0.0;
            break;
    }

    switch  (hand_controller_state) {
        case    HAND_CONT_IDLE:         //  Here for first few passes until validated direction switch reading
            break;

        case    HAND_CONT_BRAKE_WAIT:   //  Only get here after direction input changed or newly validated at power on
            pc.printf   ("At HAND_CONT_BRAKE_WAIT\r\n");
            brake_effort = 0.05;    //  Apply braking not too fiercely
            mode_set_both_motors    (MOTOR_REGENBRAKE, brake_effort);  //  Direction change 
            hand_controller_state = HAND_CONT_BRAKE_POT;
            break;

        case    HAND_CONT_BRAKE_POT:        //  Only get here after one pass through HAND_CONT_BRAKE_WAIT but
            if  (brake_effort < 0.9)    {   //   remain in this state until driver has turned pott fully anticlockwise
                brake_effort += 0.05;   //  ramp braking up to max over about one sec after direction change or validation
                mode_set_both_motors    (MOTOR_REGENBRAKE, brake_effort);  //  Direction change or testing at power on
                pc.printf   ("Brake effort %.2f\r\n", brake_effort);
            }
            else    {   //  once braking up to quite hard
                if  (pot_position < 0.02)   {   //  Driver has turned pot fully anticlock
                    hand_controller_state = HAND_CONT_STATE_BRAKING;
                }
            }
            break;

        case    HAND_CONT_STATE_INTO_BRAKING:
            brake_effort = (Pot_Brake_Range - pot_position) / Pot_Brake_Range;
            if  (brake_effort < 0.0)
                brake_effort = 0.5;
            mode_set_both_motors    (MOTOR_REGENBRAKE, brake_effort);
            old_pot_position = pot_position;
            hand_controller_state = HAND_CONT_STATE_BRAKING;
            pc.printf   ("Brake\r\n");
            break;

        case    HAND_CONT_STATE_BRAKING:
            if  (pot_position > Pot_Brake_Range)    //  escape braking into drive
                hand_controller_state = HAND_CONT_STATE_INTO_DRIVING;
            else    {
                if  (worth_the_bother(pot_position, old_pot_position))  {
                    old_pot_position = pot_position;
                    brake_effort = (Pot_Brake_Range - pot_position) / Pot_Brake_Range;
                    mode_set_both_motors    (MOTOR_REGENBRAKE, brake_effort);
//                    pc.printf   ("Brake %.2f\r\n", brake_effort);
                }
            }
            break;

        case    HAND_CONT_STATE_INTO_DRIVING:   //  Only get here after HAND_CONT_STATE_BRAKING
            pc.printf   ("Drive\r\n");
            if  (direction_new == 1)
                mode_set_both_motors   (MOTOR_FORWARD, 0.0);  //  sets both motors
            else
                mode_set_both_motors   (MOTOR_REVERSE, 0.0);
            hand_controller_state = HAND_CONT_STATE_DRIVING;
            break;

        case    HAND_CONT_STATE_DRIVING:
            if  (pot_position < Pot_Brake_Range)    //  escape braking into drive
                hand_controller_state = HAND_CONT_STATE_INTO_BRAKING;
            else    {
                if  (worth_the_bother(pot_position, old_pot_position))  {
                    old_pot_position = pot_position;
                    drive_effort = (pot_position - Pot_Brake_Range) / (1.0 - Pot_Brake_Range);
                    setVI  (drive_effort, drive_effort);   //  Wind volts and amps up and down together ???
                    pc.printf   ("Drive %.2f\r\n", drive_effort);
                }
            }
            break;

        default:
            pc.printf   ("Unhandled Hand Controller state %d\r\n", hand_controller_state);
            break;
    }       //  endof switch  (hand_controller_state) {
}

int main()
{
    int eighth_sec_count = 0;
    //  Setup system timers to cause periodic interrupts to synchronise and automate volt and current readings, loop repeat rate etc
    tick_vread.attach_us    (&ISR_voltage_reader, VOLTAGE_READ_INTERVAL_US);    //  Start periodic interrupt generator
    loop_timer.attach_us    (&ISR_loop_timer, MAIN_LOOP_REPEAT_TIME_US);    //  Start periodic interrupt generator
#ifdef  TEMP_SENSOR_ENABLE
    temperature_find_ticker.attach_us   (&ISR_temperature_find_ticker, 960);
    Temperature_pin.fall (&temp_sensor_isr);
    Temperature_pin.mode (PullUp);
    temperature_timer.start ();
#endif
    //  Done setting up system interrupt timers

    pc.baud     (9600);     //  COM port to pc
    com3.baud   (1200);     //  Once had an idea to use this for IR comms, never tried
    com2.baud   (19200);    //  Opto isolated serial bus connecting 'n' STM3_ESC boards to 1 Brute Touch Screen controller

    rpm2mph = 60.0                                                          //  to Motor Revs per hour;
              * ((double)mode.rd(MOTPIN) / (double)mode.rd(WHEELGEAR))  //  Wheel revs per hour
              * PI * ((double)mode.rd(WHEELDIA) / 1000.0)                  //  metres per hour
              * 39.37 / (1760.0 * 36.0);                                      //  miles per hour

    MotorA.direction_set    (mode.rd(MOTADIR));     //  modes all setup in class   eeprom_settings {}  mode    ; constructor
    MotorB.direction_set    (mode.rd(MOTBDIR));
    MotorA.poles            (mode.rd(MOTAPOLES));   //  Returns true if poles 4, 6 or 8. Returns false otherwise
    MotorB.poles            (mode.rd(MOTBPOLES));   //  Only two calls are here
    MotorA.set_mode         (MOTOR_REGENBRAKE);
    MotorB.set_mode         (MOTOR_REGENBRAKE);
    setVI  (0.9, 0.5);              //  Power up with moderate regen braking applied

//    T1 = 0;   Now WRONGLY hoped to be InterruptIn counting pulses from LMT01 temperature sensor
    T2 = 0; //  T2, T3, T4 As yet unused pins
//    T3 = 0;
//    T4 = 0;
//    T5 = 0; now input from fw/re on remote control box
    T6 = 0;

#ifdef  TEMP_SENSOR_ENABLE
    if  ((last_temperature_count > 160) && (last_temperature_count < 2400))   //  in range -40 to +100 degree C
        temp_sensor_exists  = true;
#endif
#ifdef  USING_DC_MOTORS
    dc_motor_kicker_timer.start   ();
#endif
    int old_hand_controller_direction = T5;
    if  (mode.rd(COMM_SRC) == 3)  {      //  Read fwd/rev switch 'T5', PA15 on 401
        pc.printf   ("Pot control\r\n");
        if  (T5)
            mode_set_both_motors   (MOTOR_FORWARD, 0.0);  //  sets both motors
        else
            mode_set_both_motors   (MOTOR_REVERSE, 0.0);
    }

    pc.printf   ("About to start %s!, mode_bytes[COMM_SRC]= %d\r\n", const_version_string, mode.rd(COMM_SRC));
    pc.printf   ("ESC_Error.all_good() ret'd %s\r\n", ESC_Error.all_good() ? "true" : "false");
//    pc.printf   ("SystemCoreClock=%d, MAX_PWM_TICKS=%d\r\n", SystemCoreClock, MAX_PWM_TICKS);
//    pcc.test    ()  ;
//    tsc.test    ()  ;

    WatchDog    = WATCHDOG_RELOAD + 80; //  Allow extra few seconds at powerup


    while   (1) {      //  Loop forever, repeats synchroised by waiting for ticker Interrupt Service Routine to set 'loop_flag' true
        while   (!loop_flag)  {         //  Most of the time is spent in this loop, repeatedly re-checking for commands from pc port
            pcc.core    ()  ;   //  Proceed beyond here once loop_timer ticker ISR has set loop_flag true
            tsc.core    ()  ;   //  Proceed beyond here once loop_timer ticker ISR has set loop_flag true
            AtoD_reader ();                     //  Performs A to D conversions at rate set by ticker interrupts
        }                       //  32Hz original setting for loop repeat rate
        loop_flag = false;              //  Clear flag set by ticker interrupt handler. WHEN LAST CHECKED this was about every 32ms

        RC_chan_1.validate_rx();   //  Tests for pulse width and repetition rates being believable signal from radio control
        RC_chan_2.validate_rx();    //  bool return values not noted here, these 2 lines are pointless.

        switch  (mode.rd(COMM_SRC))  {   //  Look to selected source of driving command, act on commands from wherever
            case    0:  //  Invalid
                break;
            case    COM1:  //  COM1    -   Primarily for testing, bypassed by command line interpreter
                break;
            case    COM2:  //  COM2    -   Primarily for testing, bypassed by command line interpreter
                break;
            case    HAND:  //  Put all hand controller input stuff here
                hand_control_state_machine  (3);
                break;  //  endof hand controller stuff
            case    RC_IN1:  //  RC_chan_1
                hand_control_state_machine  (4);
                break;
            case    RC_IN2:  //  RC_chan_2
                break;
            default:
                if  (ESC_Error.read(FAULT_UNRECOGNISED_STATE))  {
                    pc.printf   ("Unrecognised state %d\r\n", mode.rd(COMM_SRC));    //  set error flag instead here
                    ESC_Error.set   (FAULT_UNRECOGNISED_STATE, 1);
                }
                break;
        }   //  endof   switch  (mode_bytes[COMM_SRC])  {

#ifdef  USING_DC_MOTORS
        dc_motor_kicker_timer.reset   ();
#endif
        MotorA.speed_monitor_and_control   ();   //  Needed to keep table updated to give reading in Hall transitions per second
        MotorB.speed_monitor_and_control   ();   //  Read MotorX.PPS to read pulses per sec or MotorX.RPM to read motor RPM

#ifdef  USING_DC_MOTORS
        if  (MotorA.dc_motor)   {
//            MotorA.raw_V_pwm    (1);
            MotorA.low_side_on  ();
        }
        if  (MotorB.dc_motor)   {
//            MotorB.raw_V_pwm    (1);
            MotorB.low_side_on  ();
        }
        if  (MotorA.dc_motor || MotorB.dc_motor)    {
//            motors_restore.attach_us    (&restorer, ttime);
            motors_restore.attach_us    (&restorer, 25);
        }
#endif

        if  (flag_8Hz)  {   //  do slower stuff
            flag_8Hz    = false;
            LED = !LED;                   // Toggle LED on board, should be seen to fast flash
            if  (WatchDogEnable)    {
                WatchDog--;
                if  (WatchDog < 1) {   //  Deal with WatchDog timer timeout here
                    WatchDog = 0;
                    setVI  (0.0, 0.0);  //  set motor volts and amps to zero
//                    com2.printf ("TIMEOUT %c\r\n", mode.rd(BOARD_ID));   //  Potential problem of multiple units reporting at same time overcome by adding board number to WATCHDOG_RELOAD
                    pc.printf ("TIMEOUT %c\r\n", mode.rd(BOARD_ID));   //  Brute touch screen controller can do nothing with this
                }                       //  End of dealing with WatchDog timer timeout
            }
            Update_Current_Scaler   ();
            eighth_sec_count++;
            if  (eighth_sec_count > 6)    {   //  Send some status info out of serial port every second and a bit or thereabouts
                eighth_sec_count = 0;
                ESC_Error.report_any (false);   //  retain = false - reset error after reporting once
                /*                if  (temp_sensor_exists)    {
                                    double  tmprt = (double) last_temp_count;
                                    tmprt /= 16.0;
                                    tmprt -= 50.0;
                                    pc.printf   ("Temp %.2f\r\n", tmprt);
                                }*/
            }
//#define SERVO_OUT_TEST
#ifdef  SERVO_OUT_TEST
    static double  servo_angle = 0.0;  //  For testing servo outs
            //  servo out test here     December 2018
            servo_angle += 0.01;
            if  (servo_angle > TWOPI)
                servo_angle -= TWOPI;
            Servo1 = ((sin(servo_angle)+1.0) / 2.0);
            Servo2 = ((cos(servo_angle)+1.0) / 2.0);
            //  Yep!    Both servo outs work lovely December 2018
#endif
        }   //  End of if(flag_8Hz)
    }       //  End of main programme loop
}