Timing.h

// easy to use timing that handles millis() overflow
// example:
// create timer:    Timing mytimer;
// in setup():      mytimer.begin(0); // 0=catchup, 1=always use delay even if late
// in loop():       if (mytimer.isOver(1000) {
//                                           do something every 1000ms
//                                           }
// This file Copyright (c) 2016 Peter Scargill
//
#ifndef Timing_h
#define Timing_h
#include <Arduino.h>

class Timing
{
private:
 unsigned long counter;
 boolean catchup;

public:
    void begin(boolean cat)
    {
        counter=millis();
        catchup=cat;
    }

    boolean onTimeout(unsigned long interval)
    {
        unsigned long newmillis=millis();  // temp vars so easier comparison
        if ((newmillis-counter)>=interval)
            {
            if (catchup) counter=newmillis; else counter+=interval;
            return true;
            }
        return false;
    }

    void onTimeout(unsigned long interval, void (*g)()) // this version pass function as parameter
    {
        unsigned long newmillis=millis();  // temp vars so easier comparison
        if ((newmillis-counter)>=interval)
            {
            if (catchup) counter=newmillis; else counter+=interval;
            g();
            }
    }
};
#endif