Beep using PWM and speaker
Fork of beep by
Diff: Beep.cpp
- Revision:
- 1:cfc88789e54f
- Parent:
- 0:080ef5594cce
diff -r 080ef5594cce -r cfc88789e54f Beep.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Beep.cpp Mon Jul 23 12:24:59 2018 +0000 @@ -0,0 +1,58 @@ +#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) { + float freq = 1046.50; + _pwm.period(1.0f/freq); + _pwm.write(0.0f); // after creating it have to be off +} + + /** stop the beep instantaneous + * usually not used + */ +void Beep::nobeep() { + _pwm.write(0.0f); +} + +/** 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(1.0f/freq); + _pwm.write(0.5f); // 50% duty cycle - beep on + toff.attach(this,&Beep::nobeep, time); // time to off +} + + + +