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Piezo Class Reference

Piezo Class Reference

Class for the PWM Piezo speaker. More...

#include <Piezo.h>

Public Member Functions

 Piezo (PinName Pwmout)
 Constructor, Pin must be PWM capable.
void play (float, int)
 Blocking function for playing sound of given frequency and duration in ms.
void playAsync (float, int)
 Nonblocking function for playing sound of given frequency and duration in ms.
void stop ()
 Function for stopping all sounds.

Detailed Description

Class for the PWM Piezo speaker.

This class is using PWM to make sounds with piezo speaker. Currently tested with LPC1768.

Writen by: Jan Crha (TeaPack_CZ), 2016.

Last modified: 2016-10-01

Example:

  #include "mbed.h"
  #include "Piezo.h"

  Piezo PS(p21);

  int main(){
      int playTime = 120;

      for(int i=0; i<2; i++)
      {
          PS.play(466.16,playTime);
          wait_ms(playTime);
          PS.play(415.30,playTime);
          wait_ms(playTime);
    
          PS.play(466.16,playTime);
          wait_ms(playTime);
          PS.play(349.23,playTime);
          wait_ms(playTime);
    
          PS.play(277.18,playTime/2);
          wait_ms(playTime/2);
          PS.play(349.23,playTime/2);
          wait_ms(playTime/2);
          wait_ms(playTime);
          PS.play(233.08,playTime/2);
          wait_ms(playTime/2);
    
          wait_ms(playTime*4);
      }
  }

Definition at line 51 of file Piezo.h.


Constructor & Destructor Documentation

Piezo ( PinName  Pwmout )

Constructor, Pin must be PWM capable.

Definition at line 3 of file Piezo.cpp.


Member Function Documentation

void play ( float  frequency,
int  duration_ms 
)

Blocking function for playing sound of given frequency and duration in ms.

Definition at line 12 of file Piezo.cpp.

void playAsync ( float  frequency,
int  duration_ms 
)

Nonblocking function for playing sound of given frequency and duration in ms.

Definition at line 25 of file Piezo.cpp.

void stop ( void   )

Function for stopping all sounds.

Definition at line 38 of file Piezo.cpp.