Input Capture on Event Mode

The counter will count from BOTTOM to MAX continuously. When an event is detected the counter value will be transferred to the Compare/Capture register (TCB.CCMP) and interrupt is generated. The module has an edge detector which can be configured to trigger count capture on either rising or falling edges.

The figure below shows the input capture unit configured to capture on falling edge on the event input signal. The interrupt flag is automatically cleared after the high byte of the capture register has been read.

Figure 1. Input Capture on Event

It is recommended to write zero to the TCB.CNT register when entering this mode from any other mode.