SWRU626 December 2025 CC3501E , CC3551E
The prescaler is an 8-bit counter which counts down from the value PRECFG.TICKDIV to zero repeatedly. The rate of the down count is referred to as the prescaler clock. When the prescaler counter reaches zero, CNTR is updated. The rate of the CNTR update is referred to as the timer clock.
The prescaler can optionally run on the system clock (80MHz) or the TICKEN signal from the Event Manager. This can be configured in the PRECFG.TICKSRC register field.
If the prescaler clock is configured to be the TICKEN event signal from the Event Manager, the source of the event must be subscribed by the GPTxEVTCTL1.TICKEN register.
The timer clock and prescaler clock determine the following: