SWRZ119 February   2022 CC1311R3

 

  1.   Trademarks
  2. 1Advisories Matrix
  3. 2Nomenclature, Package Symbolization, and Revision Identification
    1. 2.1 Device and Development Support-Tool Nomenclature
    2. 2.2 Devices Supported
    3. 2.3 Package Symbolization and Revision Identification
  4. 3Advisories
    1.     Radio_01
    2.     Power_03
    3.     I2C_01
    4.     I2S_01
    5.     CPU_01
    6.     CPU_02
    7.     CPU_Sys_01
    8.     Sys_01
    9. 3.1 Sys_05
    10.     SYSCTRL_01
    11.     IOC_01
    12.     ADC_01
    13.     ADC_02
    14.     ADC_03
  5. 4Revision History

CPU_Sys_01

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

Revisions Affected:

Revision B

Details:

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.

Workarounds:

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.