SLAZ215H October   2012  – May 2021 MSP430F449

 

  1. 1Functional Advisories
  2. 2Preprogrammed Software Advisories
  3. 3Debug Only Advisories
  4. 4Fixed by Compiler Advisories
  5. 5Nomenclature, Package Symbolization, and Revision Identification
    1. 5.1 Device Nomenclature
    2. 5.2 Package Markings
      1.      PZ100
    3. 5.3 Memory-Mapped Hardware Revision (TLV Structure)
  6. 6Advisory Descriptions
    1. 6.1  CPU4
    2. 6.2  FLL3
    3. 6.3  MPY2
    4. 6.4  PORT3
    5. 6.5  TA12
    6. 6.6  TA16
    7. 6.7  TA21
    8. 6.8  TAB22
    9. 6.9  TB2
    10. 6.10 TB14
    11. 6.11 TB16
    12. 6.12 TB24
    13. 6.13 US13
    14. 6.14 US14
    15. 6.15 US15
    16. 6.16 WDG2
    17. 6.17 XOSC9
  7. 7Revision History

6.9 TB2

TB Module

Category

Functional

Function

Interrupt is lost (slow ACLK)

Description

Timer_B counter is running with slow clock (external TBCLK or ACLK) compared to MCLK. The compare mode is selected for the capture/compare channel and the CCRx register is incremented by 1 with the occurring compare interrupt (if TBR = CCRx).
Due to the fast MCLK, the CCRx register increment (CCRx = CCRx + 1) happens before the Timer_B counter has incremented again. Therefore, the next compare interrupt should happen at once with the next Timer_B counter increment (if TBR = CCRx + 1). This interrupt is lost.

Workaround

Switch capture/compare mode to capture mode before the CCRx register increment. Switch back to compare mode afterward.