SWRZ095A January 2020 – June 2022 CC2642R-Q1
PRODUCTION DATA
The SysTick Calibration Value (Register Field CPU_SCS.STCR.TENMS) Used to Set Up 10-ms Periodic Ticks is Incorrect When the System CPU is Running Off Divided Down 48-MHz Clock
Revision F and earlier
When using the Arm® Cortex® SysTick timer, the TENMS register field (CPU_SCS.STCR.TENMS) will always shows the value corresponding to a 48-MHz CPU clock, regardless of the CPU division factor.
One of the following two workarounds must be implemented:
Workaround 1: Do not use a divided down system CPU clock. In general, power savings are maximized by completing a task at full clock speed and then stopping the system CPU entirely after the task is complete.
Workaround 2: Read the system CPU division factor from the PRCM.CPUCLKDIV.RATIO register and compensate the TENMS field in software based on this value.
TI-provided drivers do not offer any functionality to divide the system CPU clock.