Timers can be used for example to measure elapsed time or PWM signal generation. This timer is clocked by the internal clock source. The Timer in this case is a special countdown timer. It uses an 8 bit timer, which is Timer 2 in both ATmega328P and ATmega2560 chips. Every tick increases a 64 bit global variable created in OzTimer.h. You can declare a lot of timers, because these are virtual timers based on the preciseness of Timer 2. You can set the initial value of the countdown timers to any year, day, hour, minute, second, millisecond and microsecond. It will start countdown immediately. The virtual timers will tick simultaneously. You can stop them all anytime. After any virtual timer finishes countdown it can run a predefined function that is added to the programcode.

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