File content as of revision 0:3a132f85c1a8:

#include "mbed.h"

DigitalOut myled(LED1);
Serial pc (USBTX,USBRX);
Timer t;

int main()
{
    float run_time = 5.0;
    float start_Hz = 1.0, stop_Hz = 2.0;
    float amplitude;
    

    pc.printf("\n\r Enter Start frequency (Hz): ");
    pc.scanf("%f", &start_Hz);
    pc.printf("%f",start_Hz);
    
    pc.printf("\n\r Enter Stop frequency (Hz): ");
    pc.scanf("%f", &stop_Hz);
    pc.printf("%f",stop_Hz);
    
    pc.printf("\n\r Enter Amplitude (encoder counts): ");
    pc.scanf("%f", &amplitude);
    pc.printf("%f",amplitude);
    
    pc.printf("\n\n\r Press any key to start test...");
    pc.getc();
    
    float w1 = start_Hz * 3.14159 * 2;
    float w2 = stop_Hz * 3.14159 * 2; 
    float a = (w2 - w1) / (2 * run_time); 
    float b = w1;    
    float now;
       
    t.start();

    while(t.read() < run_time) {
        now = t.read();
        pc.printf("\n\r%f",amplitude * sin((a*now*now)+(b*now)));
    }

}