File content as of revision 96:93d556043569:

/*
    ECE 3140 - Spring 2019
    Lab #6 - Final Project
    04//25/2019 - 05/17/2019
    Nicole Lin (nl392) & Tyler Sherman (tss86)
*/
#include "mbed.h"

/*----------------------------------------------------------------------------
                            GLOBAL VARIABLES
 *----------------------------------------------------------------------------*/
const double pi = 3.141592653589793238462;
double offset = 65535/2;
double amplitude = 65535/2;     //this controls VOLUME
double freq = 2000.0;           //frequency in Hz --> controls TONE

DigitalOut led1(LED1);          //Red LED
AnalogOut aout(DAC0_OUT);       //DAC0_OUT = Analog Out pin = J4-P11

/*----------------------------------------------------------------------------
                        MAIN FUNCTION - Begin Program
 *----------------------------------------------------------------------------*/
int main()
{
    f = freq/1000000.0;         //convert seconds-->microseconds
    Timer clock;                //begin time
    clock.start();              //counts time in microseconds
    uint16_t sample;            //voltage to be output
    led1 = !led1;               //turn on LED to indicate operation

    while (1) {
        sample = (uint16_t)((amplitude)*sin(2.0*pi*f*clock.read_us())+offset);
        aout.write_u16(sample);
    }
}