File content as of revision 2:a34405c20cf5:

#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
}