File content as of revision 6:f4d91041b8af:

#include "mbed.h"
#include "math.h"

#include "QEI.h"

#include "rtos.h"
#include "FastPWM.h"

#define ERROR_LIMIT_POS 0.008 //limits for when any error measurement is considered to be zero.
#define ERROR_LIMIT_NEG -0.008

#define CHAN_1 0x80
#define CHAN_2 0x90
#define CHAN_3 0xA0
#define CHAN_4 0xB0

#define PRESSURE_CHAN 1
#define POSITION_CHAN 3



const double MAX_SPEED_MMPS = 24.3457;
int intDummy;
SPISlave slave(PA_7, PA_6, PA_5, PA_4 ); // mosi, miso, sclk, ssel

QEI wheel (PB_5, PB_4, NC, 256, QEI::X4_ENCODING);

DigitalOut Mntr(D3);
DigitalOut Mntr2(PB_8);
   
#define EXTERNAL_CLOCK_MODE 0x08
#define RANGE_CONFIG 0x03

#define EXTERNAL_CLOCK_MODE 0x08
#define RANGE_CONFIG 0x03 //config for 1.5*Vref = 6.144V

#define PRESSURE_BIAS_VOLTAGE 0.15151515151515 

const double MAX_ACTUATOR_LENGTH = 52.2;

const double MAX_POSITION_MM = 40.0; //maximum actuator position position in mm

//sample time variables
double dblSampleTime_s = 0.001;

#define POT_2_MM 0.006750412 //convert potentiometer reading to mm (Tested and is right)
#define POT_OFFSET 7500//6666

Serial pc(USBTX, USBRX); // tx, rx

Thread PositionControlThread(osPriorityHigh);
Thread DebugThread(osPriorityNormal);
Thread GateControlThread(osPriorityNormal);

Thread DutyCycleThread(osPriorityRealtime);
Mutex mutDutyCycle;
Semaphore semDutyCycle(1);
Timer timerDutyCycle;

volatile unsigned int intT;
volatile unsigned int intDeltaT;
double dblDutyCycle;

double dblSensorDriftError;

short randomvar;

volatile int dataRx;

void CalculateDutyCycle()
{
    while(1)
    {
        semDutyCycle.wait();
        mutDutyCycle.lock();
        dblDutyCycle = (double) intDeltaT/intT;
        mutDutyCycle.unlock();
    }
}

Semaphore semPosCtrl(1);
Semaphore semDebug(1);
Semaphore semGate(1);

Timer timer;

long pulsesTest;

//define all pins
SPI spi(PB_15, PB_14, PB_13); // mosi, miso, sclk //DO NOT USE D4 OR D5 !!!
   
DigitalOut cs_ADC(PB_12);

DigitalOut pinGate(PA_8);

AnalogIn pinDemand1(PA_0);
AnalogIn pinDemand2(PA_1);

AnalogIn pinCurSense(PB_0);

FastPWM pinPwmOutput(PC_8);

FastPWM pinSigOut(D2);

DigitalOut pinDirectionFwd(PA_13);//INB
DigitalOut pinDirectionRev(PA_14);//INA

//define all variables

int ii,jj,kk,nn, spiTick; //counting variables

volatile int slaveReceivePos;
volatile int slaveReceiveVel;
    
volatile int dataFlag;
volatile int intFeedBack_pos;
volatile int intFeedBack_pres;

int intChkSum_pos;
int intChkSum_vel;

int intPar_pos;
int intPar_vel;

//raw Data Readings
int intPotRead = 0;
int intPressureRead = 0;
double analogReadingDemPos;
double analogReadingDemVel;
double analogReadingCurSens;

char buf[10];
int dataReceived;




//system state variables 
double dblPos[10];//current position in mm
double dblPosFil[10];//current position in mm
double dblLastPos;//previous position in mm
double dblVel[10];//velocity in mm/s
double dblAccel; //acceleration in mm/s^2
double dblIntegral = 0;//integral of position;

double dblPotPositionRead;

double dblPosBias = 48.0;

double dblStartingPos;

//demand variables
double dblPosD[10];
double dblLastPosD;
double dblVelD[10];
double dblAccelD;

double dblTargetPos;
double dblTargetVel;
double dblLinearPath;
double dblLastLinearPath;
double dblPathSign;



double dblError;
double dblLastError;
double dblErrorDot;

//filter Variables
int intPosFilOrder = 0;
int intVelFilOrder = 1;
int intDemPosFilOrder = 6;
int intDemVelFilOrder = 6;
int intOutFilOrder = 0;

double dblPressureVal_norm;
double dblPressureVal_bar;

//controller variables 
double omega;
double zeta;

double Kp = 20.0;
double Ki = 2.0;
double Kd = 1.5;


double dblIntTerm; 
double dblIntLimit = 0.8;
int RXFlag;
double dblControlBias = 0.0;

double dblMotorVoltage = 12.0;

double output[10];//controller output 

//current limit variables
double CurrentLimitSet;
double dblCurrentLimitAmps = 3.0;
double currentBuck;
double currentBuckGain = 3.0;

//Pressure Limitation
const double dblPressureLimitBar = 10.0;
double dblPressureLimitGain = 2.0;
double dblPressureLimitBuck;
double dblPressureLimitDerivativeGain = 0.1;
double dblLastErrorPressure;
    double dblErrorPressure;
    double dblDeltaErrorPressure;

Timer gateTimer;  

//define custom Functions
   
bool CheckMessage(int msg) {//checks if message was corrupted
    // Find message parity
    short int count = 0;
    for(short int i=0; i<32; i++) {
        if( msg>>1 & (1<<i) ) count++;
    }
    int intParity = !(count%2);
    // Find message CheckSum    
    int intChkSum = 0;
    int intTempVar = msg>>7;
    while(intTempVar > 0) {
        intChkSum += intTempVar%10;
        intTempVar = int(intTempVar/10);
    }
    // Check if parity, CheckSum and mesage type match
    bool isParityCorrect = (intParity == (msg&0x1));
    bool isChkSumCorrect = (intChkSum == ((msg>>2)&0x1F));
    bool isCheckPassed = (isParityCorrect && isChkSumCorrect);
    return isCheckPassed;
}

////////For Carafino: Start/////////


//Message checking (For Carafino)
bool PerformSlaveSPI(SPISlave *spiSlave, unsigned int outboundMsgs[], unsigned int inboundMsgsData[]) {//performs the SPI transaction
   
    unsigned int dummyMsg = 0x5555;
    bool isSuccess = true;
    unsigned int inboundMsg, typeBit;
    short int numPacketsReceived = 0;
    for(short int i=0; i<3; i++) { // Loop 3 times for 3 SPI messages
        while( gateTimer.read_us() < 500 ) {
            if( spiSlave->receive() ) {
                numPacketsReceived++;
                
                inboundMsg = spiSlave->read();
                Mntr = 1;//dummy variable used to check function
                if(i==0) { 
                     spiSlave->reply(outboundMsgs[0]);
                } else if(i==1) {
                     spiSlave->reply(outboundMsgs[1]);
                } else {
                     spiSlave->reply(dummyMsg);
                }
                Mntr = 0;
                
                if((unsigned int)inboundMsg != dummyMsg) { // Message is not dummy which is only used for reply
                    typeBit = inboundMsg>>1 & 0x1;//extracts type bit from message, 0 = target Position; 1 = target Velocity
                    inboundMsgsData[typeBit] = inboundMsg>>7 & 0x1FF;//this contains the data recieved from master
                    if( !CheckMessage(inboundMsg) ) {
                        isSuccess = false;
                    }
                }
                break;
            }
        }
    }
    if( numPacketsReceived != 3 ) {//if it hasn't received three messages, it failed.
        isSuccess = false;
    }
    return isSuccess;
}

////////For Carafino: End/////////
   
int Read14BitADC(int channel, DigitalOut CSpin)
{
    char message;
    unsigned int outputA;
    unsigned int outputB;
    int output;

    switch(channel)
    {
        case 1:
            message = CHAN_1;
            break;
    
        case 2:
           message = CHAN_2;
           break;
    
        case 3:
           message = CHAN_3;
           break;
        case 4:
           message = CHAN_4;
           break;
           
        default:
        message = CHAN_1;
    }
    
    spi.format(8,0);
    spi.frequency(3000000);//3MHz clock speed (3.67MHz max)
    
    CSpin.write(0);
    spi.write(message);
    spi.write(0x00);
    outputA = spi.write(0x00);
    outputB = spi.write(0x00);
    CSpin.write(1);
    
    //convert result to sensible value
    outputA = outputA<<8;
    output =  outputA | outputB;
    output = output>>2;
    
    return output;
}
    
void ADC_Config()
{
    
     unsigned int msg;
    spi.format(8,0);
    spi.frequency(3000000);//3MHz clock speed (3.67MHz max)
    
    msg = CHAN_1 | RANGE_CONFIG; //config channel 1 set Vref as 
    cs_ADC = 0;
    spi.write(msg);
    cs_ADC = 1;
    
    cs_ADC = 0;
    spi.write(EXTERNAL_CLOCK_MODE);
    cs_ADC = 1;
    
    msg = CHAN_2 | RANGE_CONFIG; //config channel 2
    cs_ADC = 0;
    spi.write(msg);
    cs_ADC = 1;
    
    cs_ADC = 0;
    spi.write(EXTERNAL_CLOCK_MODE);
    cs_ADC = 1;
        
    msg = CHAN_3 | RANGE_CONFIG; //config channel 3
    cs_ADC = 0;
    spi.write(msg);
    cs_ADC = 1;
    
    cs_ADC = 0;
    spi.write(EXTERNAL_CLOCK_MODE);
    cs_ADC = 1;
    
    msg = CHAN_4 | RANGE_CONFIG; //config channel 4
    cs_ADC = 0;
    spi.write(msg);
    cs_ADC = 1;
    
    cs_ADC = 0;
    spi.write(EXTERNAL_CLOCK_MODE);
    cs_ADC = 1;
    
}
    
    
int SumDigits(int var)
{
    int intSumResult = 0;
    int intTempVar = var;
    while (intTempVar >0)
    {
        intSumResult += intTempVar%10;
        intTempVar = int(intTempVar/10);
        //intSumResult += int(var/100)%100;
    }
    
    return intSumResult;
}

//int EvenParityBitGen(int var)
int OddParityBitGen(int var)
{
    unsigned int count = 0, i, b = 1;

    for(i = 0; i < 32; i++){
        if( var & (b << i) ){count++;}
    }

    if( (count % 2) ){
        return 0;
    }

    return 1;
}
    
void CloseGate()
{
    pinGate = 0;
    
}
    
  
  

void PositionControlPID()
{
   while(1)
   {
   semPosCtrl.wait();
    
    Mntr2 = !Mntr2;
   //Mntr2 = 1 - Mntr2;//!led; 
   pulsesTest = wheel.getPulses();

   double testy = (double) abs(pulsesTest)/2000;
   pinSigOut.write(testy);
   
   //take all readings
    
    //sensor readings
    
    intPressureRead = (Read14BitADC(PRESSURE_CHAN, cs_ADC));//read pressure
    
    dblPressureVal_norm = ((double) intPressureRead/16383.0);
    dblPressureVal_norm = dblPressureVal_norm*6.144;//convert to voltage
    dblPressureVal_norm = dblPressureVal_norm - 0.5;//subtract offset
    dblPressureVal_norm = dblPressureVal_norm/4.0;//calculate normalised pressure
    
    if (dblPressureVal_norm >1.0)
    {
        dblPressureVal_norm = 1.0;
    }
    if (dblPressureVal_norm < 0.0)
    {
        dblPressureVal_norm = 0.0;
    }
    
    double pressureCheck;
    
    //intPressureRead = intPressureRead-1334;
    //intPressureRead = intPressureRead-1679;
    
    //dblPressureVal_bar = ( (double) intPressureRead/10667)*10.0;
    //pressureCheck = ( (double) intPressureRead/10667)*10.0;
    dblPressureVal_bar = dblPressureVal_norm * 25.0;
     
    //intFeedBack_pres = (int)(((double)intPressureRead/10667) * 511);
    intFeedBack_pres = (int) (dblPressureVal_bar/12*511);
    
    if(intFeedBack_pres > 511)
    {
        intFeedBack_pres = 511;
    }
    if(intFeedBack_pres < 0)
    {
        intFeedBack_pres = 0;
    }
    
    //printf("%f\t",dblPos[0]);
    //printf("%d\t",intPressureRead);
    //printf("\r\n");
    
    
    //intFeedBack_pres = intFeedBack_pres>>5;
   
    intFeedBack_pres = (intFeedBack_pres<<5) | SumDigits(intFeedBack_pres);//add checksum
    intFeedBack_pres = (intFeedBack_pres<<1);
    intFeedBack_pres = intFeedBack_pres | 0x0001; //add type (1 for pressure)
    intFeedBack_pres = (intFeedBack_pres <<1) | OddParityBitGen(intFeedBack_pres);//add parity
    intFeedBack_pres =  intFeedBack_pres & 0xFFFF;

    unsigned short garb = 0x01;
           
    intPotRead = (16383-Read14BitADC(POSITION_CHAN, cs_ADC));//read potentiometer
    dblPotPositionRead = (double) POT_2_MM*(intPotRead  - POT_OFFSET);
    
    
    //demand Readings

    
    //current reading
    analogReadingCurSens = (double) 0.3*pinCurSense.read()+0.7*analogReadingCurSens;
    
    //convert units and filter
    
     //get position and filter
    dblPos[0] = (double) pulsesTest*-0.0078125 + dblStartingPos;
    dblSensorDriftError = dblPotPositionRead - dblPos[0];
    
    if(dblSensorDriftError > 2.0)//if encoder reading is seriously wrong
    {
        //dblPos[0] = dblPotPositionRead;
    }
    
    
    if(intPosFilOrder > 0)
    {
        for (ii = 1; ii<intPosFilOrder+1; ii++)
        {
            dblPos[ii] = (double) 0.7*dblPos[ii-1] + 0.3*dblPos[ii];
        }
    }
    else
    {
        dblPos[intPosFilOrder] = dblPos[0];
    }

    //get velocity and filter
    dblVel[0] = dblPos[intPosFilOrder] - dblLastPos;
    if(intVelFilOrder>0)
    {
        for (ii = 1; ii<intVelFilOrder+1; ii++)
        {
            dblVel[ii] = (double) 0.7*dblVel[ii-1] + 0.3*dblVel[ii];
        }
    }
    else
    {
        dblVel[intVelFilOrder] = dblVel[0];
    }
    
    
    
    intFeedBack_pos = (int) ((dblPos[intPosFilOrder]/MAX_ACTUATOR_LENGTH)*511);
    
    if(intFeedBack_pos>511)
    {
        intFeedBack_pos = 511;
    }
        
    if(intFeedBack_pos<0)
    {
        intFeedBack_pos = 0;
    }
    
    //printf("%d\r\n",dblPos[intPosFilOrder]);      
    intFeedBack_pos = (intFeedBack_pos<<5) | SumDigits(intFeedBack_pos);//add checkSum
    intFeedBack_pos = intFeedBack_pos <<1; // add type (0 for position)
    intFeedBack_pos = (intFeedBack_pos <<1) | OddParityBitGen(intFeedBack_pos);//add parity
    
    //intFeedBack = dblSensorDriftError*8191;
        
    
    ///////////////PATH GENERATION////////////////////////
    //work out next path point
    double dblPathDifference;
    dblPathDifference = dblTargetPos - dblLinearPath;
    dblPathSign = dblPathDifference/fabs(dblPathDifference); //is velocity positive or negative?

    //check if target has not been reached (with additional 1% of step to be sure)
    if (fabs(dblPathDifference) > 1.01*dblTargetVel*dblSampleTime_s) {
        dblLinearPath = dblLinearPath + dblPathSign*dblTargetVel*dblSampleTime_s;//next point in path
    }
    else { //if path is very close to target position
        dblLinearPath = dblTargetPos;
    }
    
    //limit position
    if(dblLinearPath > MAX_POSITION_MM){
        dblLinearPath = MAX_POSITION_MM;
    }
    if (dblLinearPath < 0.0){
        dblLinearPath = 0.0;
    }
    
    dblPosD[intDemPosFilOrder] = 0.07*dblLinearPath + 0.93*dblPosD[intDemPosFilOrder];
    
    //make sure path is safe
    if (dblPosD[intDemPosFilOrder] > MAX_POSITION_MM) {
        dblPosD[intDemPosFilOrder] = MAX_POSITION_MM;
    }
    if (dblPosD[intDemPosFilOrder] < 0.0) {
        dblPosD[intDemPosFilOrder] = 0.0;
    }
     
    dblVelD[0] = dblPosD[intDemPosFilOrder] - dblLastPosD;
    
    ///////////////////////////////////////////////////// End of Path Generation
    
    
    //run PID calculations
    //get errors
    dblError = dblPosD[intDemPosFilOrder] - dblPos[intPosFilOrder];
    dblErrorDot = dblVelD[intDemVelFilOrder] - dblVel[intVelFilOrder];
    //get integral

    
    dblIntTerm = dblIntTerm + Ki*dblError;
    
    //limit integral term
    if (dblIntTerm > dblIntLimit)
    {
        dblIntTerm = dblIntLimit;
    }
    if (dblIntTerm < -1.0*dblIntLimit)
    {
        dblIntTerm = (double) -1.0*dblIntLimit;
    }
    
    if(fabs(dblError) <0.01)
    {
        dblError = 0.0;
        dblErrorDot = 0.0;
        
    }
        
    if (fabs(dblErrorDot) < 0.1)
    {
    dblErrorDot = 0.0;
    }
    
    //calculate output
    
    
    output[0] = Kp*dblError + dblIntTerm + Kd*dblErrorDot;
    
    //tryPressureControl
//    double dblPosCtrlOut = Kp*dblError + dblIntTerm + Kd*dblErrorDot;
//    
//    double Ki_pres = 10.0;
//    double Kp_pres = 1;
//    
//    double dblPressureError;
//    double dblPressureErrorIntTerm;
//    
//    dblPressureError = dblPosCtrlOut - Pressure
    
    //limit output
    if (output[0] > 0.95)
    {
        output[0] = 0.95;
    }
    if (output[0] < -0.95)
    {
        output[0] = -0.95;
    }
    
    if(intOutFilOrder>0)
    {
        for (ii = 1; ii < intOutFilOrder+1; ii++)
        {
            output[ii] = 0.7*output[ii-1] + 0.3*output[ii];
        }
    }
    else
    {
        output[intOutFilOrder] = output[0];
    }
    
    
    
    //limit pressure
    if (dblPressureVal_bar >dblPressureLimitBar)
    {
        dblErrorPressure = dblPressureVal_bar - dblPressureLimitBar;
        dblDeltaErrorPressure = dblErrorPressure - dblLastErrorPressure;
        
        dblPressureLimitBuck = dblPressureLimitGain * dblErrorPressure;
        dblPressureLimitBuck = dblPressureLimitBuck + (dblPressureLimitDerivativeGain*dblDeltaErrorPressure);
        dblPressureLimitBuck = dblPressureLimitBuck *1.9/2.0;
        dblLastErrorPressure = dblErrorPressure;
    }
    else
    {
        dblPressureLimitBuck = 0.0;
    }
    
    if (dblPressureLimitBuck < 0.0)
    {
        dblPressureLimitBuck = 0.0;
    }
    if (dblPressureLimitBuck > 1.9)
    {
        dblPressureLimitBuck = 1.9;
    }
    
    output[intOutFilOrder] = output[intOutFilOrder] - dblPressureLimitBuck;
    
    //limit output
    if (output[intOutFilOrder] > 0.95)
    {
        output[intOutFilOrder] = 0.95;
    }
    if (output[intOutFilOrder] < -0.95)
    {
        output[intOutFilOrder] = -0.95;
    }
    
    //limit current
    if (analogReadingCurSens> CurrentLimitSet)
    {
        currentBuck = CurrentLimitSet / analogReadingCurSens / currentBuckGain;
    }
    else
    {
        currentBuck = 1.0;
    }
    
    if (currentBuck >1.0)
    {
        currentBuck = 1.0;
    }
    
    if (currentBuck <0.0)
    {
        currentBuck = 0.0;
    }
                
    output[intOutFilOrder] = currentBuck*output[intOutFilOrder];
    //end Current limit

    //find direction
    if(output[intOutFilOrder] >=0.0)
    {
        pinDirectionFwd = 1;
        pinDirectionRev = 0;
        dblControlBias = 0.0;
    }
    else
    {
        pinDirectionFwd = 0;
        pinDirectionRev = 1;
        dblControlBias = 0.0;
    }
    
    pinPwmOutput.write(abs(output[intOutFilOrder])+dblControlBias);
    
    //update all past variables
    dblLastPos = dblPos[intPosFilOrder];
    dblLastPosD = dblPosD[intDemPosFilOrder];
    
    ///////////////////Communication (For Carafino: Start)////////////////////////////////
    
    //Message handling MCU can only receive messages when gate is 'open'. Gate opens for 500us every 1ms.
    gateTimer.reset();//resets the gate timer
    pinGate = 1;//gate is open. Sets digital output pin to HIGH
    unsigned int outboundMsgs[2] = { intFeedBack_pos , intFeedBack_pres };//prepare feedback messages
    unsigned int inboundMsgsData[2] = {0,0};
    while(gateTimer.read_us() < 500) {//while gate is open
        
        if(slave.receive()) {//when a message is received
            
            bool isSPIsuccess = PerformSlaveSPI(&slave,outboundMsgs,inboundMsgsData);//process the data and check if it was corrupted
            
            if( isSPIsuccess ) {//if message looks OK
                dblTargetPos = (double)MAX_POSITION_MM*inboundMsgsData[0]/511; //set target position  (9-bit value)
                if(dblTargetPos>MAX_POSITION_MM) { // Limit demand to ensure safety
                    dblTargetPos = MAX_POSITION_MM;
                } else if(dblTargetPos<0.0) {
                    dblTargetPos = 0.0;
                }
                
                dblTargetVel = (double)MAX_SPEED_MMPS*inboundMsgsData[1]/511;//set target velocity  (9-bit value)
                
                if(dblTargetVel>MAX_SPEED_MMPS) {
                    dblTargetVel = MAX_SPEED_MMPS;
                } else if(dblTargetVel<0.0) {
                    dblTargetPos = 0.0;
                }
                
                break;//bail out of while loop
            }
            
        }
        
    }
    
    pinGate = 0;//close gate

/*
   printf("%f\t",dblPos[intPosFilOrder]);
   printf("%f\t",dblPosD[intDemPosFilOrder]);
   printf("%f\t",dblTargetPos);
   printf("%f\t",dblError);
   printf("\r\n");
   */
   
    }
}
   //////////////////////////////////////////////////For Carafino: End
   
   
//configure all control parameters
void ControlParameterConfig()
{
   Kp = Kp/dblMotorVoltage;
   Kd = Kd/dblSampleTime_s/dblMotorVoltage;
   Ki = Ki*dblSampleTime_s/dblMotorVoltage;
}

Ticker debugTicker;

void startPositionControl()
{
    semPosCtrl.release();
}

void startDebug()
{
    semDebug.release();
}

Ticker positionCtrlTicker;
   
int main() {
    pinGate = 0;
    pc.baud(115200);
    cs_ADC = 1;
    Mntr = 0;
    Mntr2 = 0;
    pinPwmOutput.period_us(50);
    printf("\r\nYo Yo Yo, Low Level innit\r\n\n\n");
    wait(0.5);
    
    timer.start();
    gateTimer.start();
    //cs_ADC = 1;
    
    ControlParameterConfig();
//    for (ii = 0; ii< 10; ii++)
//    {
//        uintPotRead = Read14BitADC(3, cs_ADC);//read potentiometer
//        dblStartingPos = (double) POT_2_MM*uintPotRead  - dblPosBias;
//    }
//    
    slave.format(16,2);
    slave.frequency(10000000);
    
    dblPosD[intDemPosFilOrder] = 0.0;
    slaveReceivePos = 0.0;
    slaveReceiveVel = 0.0;
    wait(0.1);
    ADC_Config();
    wait(0.1);
    ADC_Config();
    wait(0.1);
    intPotRead = (16383-Read14BitADC(POSITION_CHAN, cs_ADC));//read potentiometer
    //intPotRead = (Read14BitADC(POSITION_CHAN, cs_ADC));//read potentiometer
    dblStartingPos = (double) POT_2_MM*(intPotRead  - POT_OFFSET);
    dblLinearPath = dblStartingPos;
    dblTargetPos = dblStartingPos;
    dblPos[intPosFilOrder] = dblStartingPos;
    dblTargetVel = 0.0;
    dblPosD[intDemPosFilOrder] = dblStartingPos;
    
    dblTargetPos = 0.0;
    dblPos[intPosFilOrder] = dblStartingPos;
    dblTargetVel = 3.0;
    
    printf("\r\nPotRead: %d, Current Pos: %f, Target Pos: %f\r\n", intPotRead, dblStartingPos, dblTargetPos);
        
    //calculate/convert variables
    
    CurrentLimitSet = dblCurrentLimitAmps *0.14/3.3;
    slave.reply(0x5555);
    PositionControlThread.start(PositionControlPID);

    positionCtrlTicker.attach(&startPositionControl, dblSampleTime_s);
    
    intFeedBack_pos = 0;
    intFeedBack_pres = 0;
    
    
    while(1) 
    {
        Thread::wait(osWaitForever);
    }
}