File content as of revision 2:d7286c36595f:

#include "mbed.h"
//#include "HIDScope.h"
#include "QEI.h"
#include "MODSERIAL.h"
//#include "BiQuad.h"
#include "FastPWM.h"

// Button and potmeter control
InterruptIn button1(D11);
InterruptIn button2(D10);
AnalogIn potmeter(A0);

// Encoder
DigitalIn encA(D13);
DigitalIn encB(D12);
QEI encoder(D13,D12,NC,64,QEI::X4_ENCODING);
float Ts = 0.01;
float angle;
float omega;


// Motor
DigitalOut motor2Direction(D4);
FastPWM motor2Power(D5);
DigitalOut motor1Direction(D7);
FastPWM motor1Power(D6);

//Motorcontrol
bool motordir;
double motorpwm;
float u1;
double u2;
double potValue;
double pi2= 6.283185;
float e; //e = error
float Kp=0.1;
float Ki=0.1;
float Kd=0.7;
float u_k;
float u_i;
float u_d;
// PC connection
MODSERIAL pc(USBTX, USBRX);

// Intializing tickers
Ticker motorTicker;
Ticker controlTicker;
Ticker directionTicker;
Ticker encoderTicker;

const float PWM_period = 1e-6;

volatile int counts; // Encoder counts
volatile int countsPrev = 0;
volatile int deltaCounts;

float factorin = 6.23185/64; // Convert encoder counts to angle in rad
float gearratio = 131.25; // Gear ratio of gearbox


float PID_controller(float e){
    static float error_integral=0;
    
    //Proportional part:
    u_k=Kp*e;
    
    //Integral part
    error_integral=error_integral+e*Ts;
    u_i=Ki*error_integral;
    
    // Sum and return
    return u_k+u_i;    
}

void motorControl()
{
    angle = counts * factorin / gearratio; // Angle of motor shaft in rad
    omega = deltaCounts / Ts * factorin / gearratio; // Angular velocity of motor shaft in rad/s
    potValue= potmeter.read();
    u1= (potValue*2*pi2)-pi2;
    e=u1-angle;
    
    u2=PID_controller(e);
    
        motorpwm= abs(u2);
    if (u2<0){
        motordir= 0;}
    else {
         motordir= 1;}
    motor1Power.pulsewidth(motorpwm * PWM_period );
    motor1Direction= motordir;
}

void readEncoder()
{
    counts = encoder.getPulses();
    deltaCounts = counts - countsPrev;

    countsPrev = counts;
}

int main()
{
    pc.baud(115200);
    pc.printf("\r\nStarting...\r\n\r\n");
    
    motor1Power.period(PWM_period);
    motorTicker.attach(motorControl, 0.01);
    
    
    encoderTicker.attach(readEncoder, Ts);
   
    while (true) {

        pc.printf("Potmeter: %d \r\n", potValue);
        pc.printf("Counts: %i   DeltaCounts: %i\r\n", counts, deltaCounts);
        pc.printf("Angle:  %f   Omega:       %f\r\n", angle, omega);
        pc.printf("U1: %f   Error:  %f     \r\n",u1, e);
        
        wait(0.5);
    }
}