There are several operation modes available in the Timer Array Unit and these can be independent or combined modes. In independent modes only one channel of the timer unit is used, and we have the following available modes: The “interval timer” is a simple mode which generates an interrupt at a fixed interval. The “square wave output” mode is almost identical to the interval timer mode except that the port output is enabled. “External event count” mode is not an output, but instead an input is connected to the timer and we can count external events using the rising, or falling, or even both edges. In “Divider” operation the frequency of an input signal can be divided down using one of the timer channels. “Input pulse interval measurement” or “capture” mode can measure the time between two rising or two falling edges. And the last one is the “input high/low level width” in this case it’s almost the same as “interval measurement” but here we can measure the pulse width from high to low level or vice-versa.