File content as of revision 0:e6c8377a69d0:

#include "mbed.h"
#include <stdio.h>
#include <stdlib.h>
#include <QEI.h>


DigitalOut led1(LED1);
PwmOut pwm(p25);
DigitalOut dir(p27);
Serial pc(USBTX,USBRX);
QEI turret(p17, p18, NC, 1600);
Timer t;

float pulses;
float revs;
float dc;
float theta;
float err = 0.0;
float err_old = 0.0;
float err_ancient = 0.0;
float dc_old = 0.0;
float dc_ancient = 0.0;
float des_theta=0.0;

//float t;
//float t_2;
int yes;

Ticker Controller;
void CtrCode() {
    pulses = turret.getPulses();
    revs = -pulses / 3200.0;
    theta = revs*360.0;

    err = des_theta-theta;

    dc = 1.9703*dc_old - 0.9703*dc_ancient + .1471*err- 0.293*err_old + 0.146*err_ancient;    //1.9703*dc_old - 0.9703*dc_ancient + .1471*err - 0.293*err_old + 0.146*err_ancient;

    err_ancient = err_old;
    err_old = err;
    dc_ancient = dc_old;
    dc_old = dc;

    if (dc>0)
    {
        dir = 1;
    } else
    {
        dir = 0;
    }
    
    pwm.write(abs(dc));

}



int main()
{
    float pwm_now;

    pc.baud(9600); // set baud rate

    dir=1;
    pwm.period(1.0/(20*10^3));
    pc.printf("start?");
    pc.scanf("%d",&yes);
    Controller.attach(&CtrCode,.0083);
    des_theta = 90.0;

    while(1) {
        pc.printf("Error: %.3f, DC: %.3f\n", err, dc);
        
        
        
    }




}