Beep using PWM and speaker
Dependents: Hangman Weather_Station Ultrasonic Ultrasonicdistancesensor ... more
Revision 0:080ef5594cce, committed 2012-10-11
- Comitter:
- pprasad7
- Date:
- Thu Oct 11 20:14:49 2012 +0000
- Commit message:
- beep;
Changed in this revision
beep.cpp | Show annotated file Show diff for this revision Revisions of this file |
beep.h | Show annotated file Show diff for this revision Revisions of this file |
diff -r 000000000000 -r 080ef5594cce beep.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/beep.cpp Thu Oct 11 20:14:49 2012 +0000 @@ -0,0 +1,56 @@ +#include "beep.h" +#include "mbed.h" + +/** class to make sound with a buzzer, based on a PwmOut + * The class use a timeout to switch off the sound - it is not blocking while making noise + * + * Example: + * @code + * // Beep with 1Khz for 0.5 seconds + * #include "mbed.h" + * #include "beep.h" + * + * Beep buzzer(p21); + * + * int main() { + * ... + * buzzer.beep(1000,0.5); + * ... + * } + * @endcode + */ + +using namespace mbed; + // constructor + /** Create a Beep object connected to the specified PwmOut pin + * + * @param pin PwmOut pin to connect to + */ + +Beep::Beep(PinName pin) : _pwm(pin) { + _pwm.write(0.0); // after creating it have to be off +} + + /** stop the beep instantaneous + * usually not used + */ +void Beep::nobeep() { + _pwm.write(0.0); +} + +/** Beep with given frequency and duration. + * + * @param frequency - the frequency of the tone in Hz + * @param time - the duration of the tone in seconds + */ + +void Beep::beep(float freq, float time) { + + _pwm.period(1.0/freq); + _pwm.write(0.5); // 50% duty cycle - beep on + toff.attach(this,&Beep::nobeep, time); // time to off +} + + + +
diff -r 000000000000 -r 080ef5594cce beep.h --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/beep.h Thu Oct 11 20:14:49 2012 +0000 @@ -0,0 +1,59 @@ +#ifndef MBED_BEEP_H +#define MBED_BEEP_H + +#include "mbed.h" + +/** class to make sound with a buzzer, based on a PwmOut + * The class use a timeout to switch off the sound - it is not blocking while making noise + * + * Example: + * @code + * // Beep with 1Khz for 0.5 seconds + * #include "mbed.h" + * #include "beep.h" + * + * Beep buzzer(p21); + * + * int main() { + * ... + * buzzer.beep(1000,0.5); + * ... + * } + * @endcode + */ + + +namespace mbed { + +/* Class: Beep + * A class witch uses pwm to controle a beeper to generate sounds. + */ +class Beep { + +public: + +/** Create a Beep object connected to the specified PwmOut pin + * + * @param pin PwmOut pin to connect to + */ + Beep (PinName pin); + +/** Beep with given frequency and duration. + * + * @param frequency - the frequency of the tone in Hz + * @param time - the duration of the tone in seconds + */ + void beep (float frequency, float time); + +/** stop the beep instantaneous + * usually not used + */ + void nobeep(); + +private : + PwmOut _pwm; + Timeout toff; +}; + +} +#endif