![](/media/cache/group/default_image.jpg.50x50_q85.jpg)
dac controller for EE300 project
DAC/DAC.cpp
- Committer:
- dzl5187
- Date:
- 2014-04-04
- Revision:
- 1:4bd950ab8756
File content as of revision 1:4bd950ab8756:
#include "mbed.h" #include "mcp4725.h" #include "DAC.h" #include "math.h" #include "log.h" #define PI 3.1415926 MCP4725 controller(p9, p10, MCP4725::Fast400kHz, DEVICE_ADDR_BIT); Timer DAC_timer; bool volatile DAC_running = false; float p_range = 0; enum FREQ p_freq = FREQ_10HZ; enum FORM p_form = FORM_SQUARE; void DAC_start(){ DAC_running = true; } void DAC_stop(){ DAC_running = false; } void DAC_set(float range, enum FREQ freq, enum FORM form){ p_range = range; p_freq = freq; p_form = form; } void DAC_generate(){ float Vout = 0; int time_us = 0; DAC_timer.start(); while( DAC_running ){ if( p_form == FORM_SQUARE ){ if( p_freq == FREQ_10HZ ){ //generate square wave at 10HZ if( (int)time_us % 1000000 <= 500000){ // T = 100 ms Vout = p_range; } else Vout = 0; } else{ //generate square wave at 1HZ if( (int)time_us % 1000000 <= 500000) //T = 1 s Vout = p_range; else Vout = 0; } } else if ( p_form == FORM_SIN){ if( p_freq == FREQ_10HZ ){ Vout = p_range / 2.0 * (sin( 2.0 * PI * 10.0 * time_us / 1000000.0) + 1); } else{ //generate sin wave at 1HZ Vout = p_range / 2.0 * (sin( 2.0 * PI * 1.0 * time_us / 1000000.0) + 1); } } wait_us(1000); //delay 1 ms time_us += 1000; controller.write(MCP4725::Normal, (0xFFF * (Vout/VDD_VOLTAGE) ), false); } DAC_timer.stop(); DAC_timer.reset(); }