File content as of revision 0:b6c8d56842ce:

/**
 * Demo program for BiQuad and BiQuadChain classes
 * author: T.J.W. Lankhorst <t.j.w.lankhorst@student.utwente.nl> and Matthijs and Roy and Dion
 */
#include "mbed.h"
#include "HIDScope.h"
#include <stdlib.h>
#include <iostream>
#include <iomanip>
#include <complex>
#include "BiQuad.h"

AnalogIn    emg0( A0 );
AnalogIn    emg1( A1 );

Ticker      sample_timer;
HIDScope    scope( 2 );
DigitalOut  led(LED1);
DigitalOut  led2(LED_GREEN);



// Example: 3th order Butterworth LP (w_c = 0.1*f_nyquist)

BiQuadChain bqc;
BiQuad bq1( 0.9645651759199596, -1.5606992390030165, 0.9645651759199596, -1.5606992390030165, 0.9291303518399192 );
BiQuad bq2( 1, 1, 1, 1, 1 );
//BiQuad bq3( 0, 0, 0, 0, 0 );

void sample()
{
    /* Set the sampled emg values in channel 0 (the first channel) and 1 (the second channel) in the 'HIDScope' instance named 'scope' */
    scope.set(0, bq1.step(emg0.read()) );
    scope.set(1, bq1.step(emg1.read()) );
    /* Repeat the step above if required for more channels of required (channel 0 up to 5 = 6 channels) 
    *  Ensure that enough channels are available (HIDScope scope( 2 ))
    *  Finally, send all channels to the PC at once */
    scope.send();
    /* To indicate that the function is working, the LED is toggled */
    led = !led;
}

int main()
{   
    led2 = 0;
    bqc = bq1 * bq2; //* bq3;
    /**Attach the 'sample' function to the timer 'sample_timer'.
    * this ensures that 'sample' is executed every... 0.002 seconds = 500 Hz
    */
    sample_timer.attach(&sample, 0.002);

    /*empty loop, sample() is executed periodically*/
    while(true) {
    
    // Find the poles of the filter
    std::cout << "Filter poles" << std::endl;
    std::vector< std::complex<double> > poles = bqc.poles();
    for( size_t i = 0; i < poles.size(); i++ )
        std::cout << "\t"  << poles[i] << std::endl;

    // Find the zeros of the filter
    std::cout << "Filter zeros" << std::endl;
    std::vector< std::complex<double> > zeros = bqc.zeros();
    for( size_t i = 0; i < poles.size(); i++ )
        std::cout << "\t" << zeros[i] << std::endl;

    // Is the filter stable?
    std::cout << "This filter is " << (bqc.stable() ? "stable" : "instable") << std::endl;

    // Output the step-response of 20 samples
    std::cout << "Step response 20 samples" << std::endl;
    for( int i = 0; i < 20; i++ )
        std::cout << "\t" << bqc.step( 1.0 ) << std::endl;

    // Done0
    }

}