File content as of revision 6:9808e2c61247:

#ifndef MBED_ULTRASONIC_H
#define MBED_ULTRASONIC_H

/**
    @code
    
    #include "mbed.h"
    #include "ultrasonic.h"
    
     void dist(int distance)
    {
        //put code here to happen when the distance is changed
        printf("Distance changed to %dmm\r\n", distance);
    }
    
    ultrasonic mu(D8, D9, 100ms, 1s, &dist);    //Set the trigger pin to D8 and the echo pin to D9
                                                //have updates every .1 seconds and a timeout after 1
                                                //second, and call dist when the distance changes
    
    int main()
    {
        mu.startUpdates();//start mesuring the distance
        while(1)
        {
            //Do something else here
            mu.checkDistance();     //call checkDistance() as much as possible, as this is where
                                    //the class checks if dist needs to be called.
        }
    }
    
    @endcode
*/

#include "mbed.h"

class ultrasonic
{
    public:
        /**iniates the class with the specified trigger pin, echo pin, update speed and timeout**/
        ultrasonic(PinName trigPin, PinName echoPin, Kernel::Clock::duration_u32 updateSpeed, Kernel::Clock::duration_u32 timeout);
        /**iniates the class with the specified trigger pin, echo pin, update speed, timeout and method to call when the distance changes**/
        ultrasonic(PinName trigPin, PinName echoPin, Kernel::Clock::duration_u32 updateSpeed, Kernel::Clock::duration_u32 timeout, void onUpdate(int));
        /** returns the last measured distance**/
        int getCurrentDistance(void);
        /**pauses measuring the distance**/
        void pauseUpdates(void);
        /**starts mesuring the distance**/
        void startUpdates(void);
        /**attachs the method to be called when the distances changes**/
        void attachOnUpdate(void method(int));
        /**changes the speed at which updates are made**/
        void changeUpdateSpeed(Kernel::Clock::duration_u32 updateSpeed);
        /**gets whether the distance has been changed since the last call of isUpdated() or checkDistance()**/
        int isUpdated(void);
        /**gets the speed at which updates are made**/
        Kernel::Clock::duration_u32 getUpdateSpeed(void);
        /**call this as often as possible in your code, eg. at the end of a while(1) loop,
        and it will check whether the method you have attached needs to be called**/
        void checkDistance(void);
    private:
        DigitalOut _trig;
        InterruptIn _echo;
        Timer _t;
        Timeout _tout;
        int _distance;
        Kernel::Clock::duration_u32 _updateSpeed;
        int start;
        int end;
        volatile int done;
        void (*_onUpdateMethod)(int);
        void _startT(void);
        void _updateDist(void);
        void _startTrig(void);
        Kernel::Clock::duration_u32 _timeout;
        int d;
};
#endif