main.cpp

00001 /*
00002     ECE 3140 - Spring 2019
00003     Lab #6 - Final Project
00004     04//25/2019 - 05/17/2019
00005     Nicole Lin (nl392) & Tyler Sherman (tss86)
00006 */
00007 #include "mbed.h"
00008 
00009 /*----------------------------------------------------------------------------
00010                             GLOBAL VARIABLES
00011  *----------------------------------------------------------------------------*/
00012 const double pi = 3.141592653589793238462;
00013 double offset = 65535/2;
00014 double amplitude = 65535/2;     //this controls VOLUME
00015 double freq = 2000.0;           //frequency in Hz --> controls TONE
00016 
00017 DigitalOut led1(LED1);          //Red LED
00018 AnalogOut aout(DAC0_OUT);       //DAC0_OUT = Analog Out pin = J4-P11
00019 
00020 /*----------------------------------------------------------------------------
00021                         MAIN FUNCTION - Begin Program
00022  *----------------------------------------------------------------------------*/
00023 int main()
00024 {
00025     f = freq/1000000.0;         //convert seconds-->microseconds
00026     Timer clock;                //begin time
00027     clock.start();              //counts time in microseconds
00028     uint16_t sample;            //voltage to be output
00029     led1 = !led1;               //turn on LED to indicate operation
00030 
00031     while (1) {
00032         sample = (uint16_t)((amplitude)*sin(2.0*pi*f*clock.read_us())+offset);
00033         aout.write_u16(sample);
00034     }
00035 }