SLAZ656S February   2015  – May 2021 MSP430F6721A

 

  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
      2.      PN80
    3. 5.3 Memory-Mapped Hardware Revision (TLV Structure)
  6. 6Advisory Descriptions
    1. 6.1  ADC39
    2. 6.2  ADC42
    3. 6.3  ADC69
    4. 6.4  AUXPMM2
    5. 6.5  BSL7
    6. 6.6  BSL14
    7. 6.7  CPU21
    8. 6.8  CPU22
    9. 6.9  CPU36
    10. 6.10 CPU40
    11. 6.11 CPU46
    12. 6.12 CPU47
    13. 6.13 DMA4
    14. 6.14 DMA7
    15. 6.15 DMA9
    16. 6.16 DMA10
    17. 6.17 EEM8
    18. 6.18 EEM17
    19. 6.19 EEM19
    20. 6.20 EEM23
    21. 6.21 JTAG26
    22. 6.22 JTAG27
    23. 6.23 LCDB5
    24. 6.24 LCDB6
    25. 6.25 PMM7
    26. 6.26 PMM11
    27. 6.27 PMM12
    28. 6.28 PMM14
    29. 6.29 PMM15
    30. 6.30 PMM18
    31. 6.31 PMM20
    32. 6.32 PMM26
    33. 6.33 PORT15
    34. 6.34 PORT19
    35. 6.35 SD3
    36. 6.36 UCS11
    37. 6.37 USCI36
    38. 6.38 USCI37
    39. 6.39 USCI41
    40. 6.40 USCI42
    41. 6.41 USCI47
    42. 6.42 USCI50
  7. 7Revision History

6.36 UCS11

UCS Module

Category

Functional

Function

Modifying UCSCTL4 clock control register triggers an additional erroneous clock request

Description

Changing the SELM/SELS/SELA bits in the UCSCTL4 register will correctly configure the respective clock to use the intended clock source but might also erroneously set XT1/XT2 fault flag if the crystals are not present at XT1/XT2 or not configured in the application firmware. If the NMI interrupt for the OFIFG is enabled, an unintentional NMI interrupt will be triggered and needs to be handled.

Note: The XT1/XT2 fault flag can be set regardless of which SELM/SELS/SELA bit combinations are being changed.

Workaround

Clear all the fault flags in UCSCTL7 register once after changing any of the SELM/SELS/SELA bits in the UCSCTL4 register.
If OFIFG-NMI is enabled during clock switching, disable OFIFG-NMI interrupt  during changing the SELM/SELS/SELA bits in the UCSCTL4 register to prevent unintended NMI.
Alternatively it can be handled accordingly (clear falsely set fault flags) in the Interrupt Service Routine to ensure proper OFIFG clearing.