SWRU626 December 2025 CC3501E , CC3551E
The processor has two 24-bit system timers, a Non-secure SysTick timer and a Secure SysTick timer. When enabled, each timer counts down from the reload value to zero, reloads (wraps to) the value in the SYST_RVR on the next clock cycle, then decrements on subsequent clock cycles. When the processor is halted for debugging, the counter does not decrement.