ihsian mulla / Buzzer

Buzzzer

Dependents:   ishtendo-vI-IX-IX-V Oled_bme280

Fork of beep by Pallavi Prasad

beep.cpp@1:e29e9889cfb4, 2016-05-04 (annotated)

Committer:
Ihsianmulla
Date:
Wed May 04 13:00:51 2016 +0000
Revision:
1:e29e9889cfb4
Parent:
0:080ef5594cce 
Buzzer Library using PWM

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Ihsianmulla 1:e29e9889cfb4 1 /** Piezo Buzzer Functions
Ihsianmulla 1:e29e9889cfb4 2 * Used for creating an audible alert when starting and to indicate failure of task
Ihsianmulla 1:e29e9889cfb4 3 @file beep.cpp
Ihsianmulla 1:e29e9889cfb4 4 @brief PiezoBuzzer header file containing functions uses PWM
Ihsianmulla 1:e29e9889cfb4 5 @brief write stuff ehre
Ihsianmulla 1:e29e9889cfb4 6 @author Pallavi Prasad
Ihsianmulla 1:e29e9889cfb4 7 @date April2016
Ihsianmulla 1:e29e9889cfb4 8 */
Ihsianmulla 1:e29e9889cfb4 9
Ihsianmulla 1:e29e9889cfb4 10
pprasad7 0:080ef5594cce 11 #include "beep.h"
pprasad7 0:080ef5594cce 12 #include "mbed.h"
pprasad7 0:080ef5594cce 13
pprasad7 0:080ef5594cce 14 /** class to make sound with a buzzer, based on a PwmOut
pprasad7 0:080ef5594cce 15 * The class use a timeout to switch off the sound - it is not blocking while making noise
pprasad7 0:080ef5594cce 16 *
pprasad7 0:080ef5594cce 17 * Example:
pprasad7 0:080ef5594cce 18 * @code
pprasad7 0:080ef5594cce 19 * // Beep with 1Khz for 0.5 seconds
pprasad7 0:080ef5594cce 20 * #include "mbed.h"
pprasad7 0:080ef5594cce 21 * #include "beep.h"
pprasad7 0:080ef5594cce 22 *
pprasad7 0:080ef5594cce 23 * Beep buzzer(p21);
pprasad7 0:080ef5594cce 24 *
pprasad7 0:080ef5594cce 25 * int main() {
pprasad7 0:080ef5594cce 26 * ...
pprasad7 0:080ef5594cce 27 * buzzer.beep(1000,0.5);
pprasad7 0:080ef5594cce 28 * ...
pprasad7 0:080ef5594cce 29 * }
pprasad7 0:080ef5594cce 30 * @endcode
pprasad7 0:080ef5594cce 31 */
pprasad7 0:080ef5594cce 32
pprasad7 0:080ef5594cce 33 using namespace mbed;
pprasad7 0:080ef5594cce 34 // constructor
pprasad7 0:080ef5594cce 35 /** Create a Beep object connected to the specified PwmOut pin
pprasad7 0:080ef5594cce 36 *
pprasad7 0:080ef5594cce 37 * @param pin PwmOut pin to connect to
pprasad7 0:080ef5594cce 38 */
pprasad7 0:080ef5594cce 39
pprasad7 0:080ef5594cce 40 Beep::Beep(PinName pin) : _pwm(pin) {
pprasad7 0:080ef5594cce 41 _pwm.write(0.0); // after creating it have to be off
pprasad7 0:080ef5594cce 42 }
pprasad7 0:080ef5594cce 43
pprasad7 0:080ef5594cce 44 /** stop the beep instantaneous
pprasad7 0:080ef5594cce 45 * usually not used
pprasad7 0:080ef5594cce 46 */
pprasad7 0:080ef5594cce 47 void Beep::nobeep() {
pprasad7 0:080ef5594cce 48 _pwm.write(0.0);
pprasad7 0:080ef5594cce 49 }
pprasad7 0:080ef5594cce 50
pprasad7 0:080ef5594cce 51 /** Beep with given frequency and duration.
pprasad7 0:080ef5594cce 52 *
pprasad7 0:080ef5594cce 53 * @param frequency - the frequency of the tone in Hz
pprasad7 0:080ef5594cce 54 * @param time - the duration of the tone in seconds
pprasad7 0:080ef5594cce 55 */
pprasad7 0:080ef5594cce 56
pprasad7 0:080ef5594cce 57 void Beep::beep(float freq, float time) {
pprasad7 0:080ef5594cce 58
pprasad7 0:080ef5594cce 59 _pwm.period(1.0/freq);
pprasad7 0:080ef5594cce 60 _pwm.write(0.5); // 50% duty cycle - beep on
pprasad7 0:080ef5594cce 61 toff.attach(this,&Beep::nobeep, time); // time to off
pprasad7 0:080ef5594cce 62 }
pprasad7 0:080ef5594cce 63
pprasad7 0:080ef5594cce 64
pprasad7 0:080ef5594cce 65
pprasad7 0:080ef5594cce 66