File content as of revision 0:2d2fa105dbb0:

#include "mbed.h"
#include "FastPWM.h"
AnalogIn ref_raw(A3);
Ticker read_adc;
AnalogOut output(A2);
FastPWM pwm_output(D3);
DigitalOut testing(D2);

double raw[5] = {0, 0, 0, 0, 0};
double ref[5] = {0, 0, 0, 0, 0};
/*
double raw;
double old_raw = 0;
double old_raw_2 = 0;
double old_raw_3 = 0;
double old_raw_4 = 0;
double ref;
double old_ref = 0;
double old_ref_2 = 0;
double old_ref_3 = 0;
double old_ref_4 = 0;
*/
double b[5] = {0.000000018682489340283,   0.000000074729957361130,   0.000000112094936041696,   0.000000074729957361130,   0.000000018682489340283};
double a[5] = {1.000000000000000,  -3.938430361819403,   5.817179417349660,  -3.819034001378269,   0.940285244767841};

//double b[5] = {0.000144120224075409, 0.000576480896301634, 0.000864721344452452, 0.000576480896301634, 0.000144120224075409};
//double a[5] = {1.000000000000000, -3.384972728303897, 4.337061817421342, -2.489138293812547, 0.539355128280308};

void read_ref(void){
    //ref = 3.3*(analog_value.read()-.5);
    //output.write(ref_raw.read());
    raw[0] = .85*(ref_raw.read()-.5)+.5;
//    ref = raw;
   
    ref[0] = b[0]*raw[0]+b[1]*raw[1]+b[2]*raw[2]+b[3]*raw[3]+b[4]*raw[4]-a[1]*ref[1]-a[2]*ref[2]-a[3]*ref[3]-a[4]*ref[4];
    
    for (int i=4; i > 0; i--){
        raw[i] = raw[i-1];
        ref[i] = ref[i-1];
        }

    output.write(ref[0]);
    pwm_output.write(ref[0]+.03);
    //testing=!testing;
    }
    
int main() {
    testing=0;
    pwm_output.period(.000025);
    read_adc.attach(&read_ref, .000025);
    testing = 0;
    while(1) {
        //ref_raw.read();
        //pwm_output.write(.5);
        //ref_raw.read();
        //testing = !testing;
    }
}