Buzzer.cpp

00001 /******************** (C) COPYRIGHT 2016 Delta Electronics, Inc. ***************
00002 *
00003 * File Name : Buzzer.cpp
00004 * Authors   : Tsungta Wu - CPBG (tsungta.wu@deltaww.com)
00005 * Version   : V.1.0.1
00006 * Date      : 2016/Oct/14
00007 *
00008 *******************************************************************************/
00009 
00010 #include "Buzzer.h"
00011 #include "mbed.h"
00012 
00013 using namespace mbed;
00014  // constructor
00015  /** Create a Beep object connected to the specified PwmOut pin
00016   *
00017   * @param pin PwmOut pin to connect to 
00018   */
00019 
00020 Buzzer::Buzzer(PinName pin) : _pwm(pin) {
00021     _pwm.write(0.0);     // after creating it have to be off 
00022 }
00023 
00024 static float Int;
00025 static float* Freq;
00026 static uint16_t Num;
00027 static uint16_t tone_cnt;
00028 
00029  /**next beep instantaneous 
00030   * usually not used 
00031   */
00032   
00033 void Buzzer::stopBuzzer() {
00034   _pwm.write(0.0);
00035   tone_cnt = Num;
00036 }
00037 
00038 /** Beep with given frequency and duration.
00039  *
00040  * @param frequency - the frequency of the tone in Hz
00041  * @param time - the duration of the tone in seconds
00042  */
00043      
00044 void Buzzer::simpleBeep(float freq, float time) {
00045     _pwm.period(1.0/freq);
00046     _pwm.write(0.5);            // 50% duty cycle - beep on
00047     tnext.attach(this,&Buzzer::stopBuzzer, time);   // time to off
00048 }
00049   
00050 void Buzzer::nextTone() {
00051     if (++tone_cnt < Num) {
00052       if (Freq[tone_cnt] > 0) {    
00053         _pwm.period(1.0/Freq[tone_cnt]);
00054         _pwm.write(0.5);            // 50% duty cycle - beep on
00055       } else _pwm.write(0.0);
00056       tnext.attach(this,&Buzzer::nextTone, Int);   // time to off
00057     } else _pwm.write(0.0);
00058 }
00059 
00060 void Buzzer::playMelody (float* tone_freq, uint16_t tone_num,float tone_time) {
00061     stopBuzzer();
00062     
00063     Int = tone_time;  
00064     Num = tone_num;
00065     Freq = tone_freq;
00066     
00067     tone_cnt = 0;
00068     _pwm.period(1.0/Freq[tone_cnt]);
00069     _pwm.write(0.5);            // 50% duty cycle - beep on    
00070     tnext.attach(this,&Buzzer::nextTone, Int);   // time to off
00071 }
00072 
00073 
00074 
00075