SLAZ099AA October   2012  – May 2021 CC430F6126

 

  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.      RGC64
    3. 5.3 Memory-Mapped Hardware Revision (TLV Structure)
  6. 6Advisory Descriptions
    1. 6.1  AES1
    2. 6.2  BSL7
    3. 6.3  COMP4
    4. 6.4  COMP10
    5. 6.5  CPU18
    6. 6.6  CPU20
    7. 6.7  CPU21
    8. 6.8  CPU22
    9. 6.9  CPU23
    10. 6.10 CPU24
    11. 6.11 CPU25
    12. 6.12 CPU26
    13. 6.13 CPU27
    14. 6.14 CPU28
    15. 6.15 CPU29
    16. 6.16 CPU30
    17. 6.17 CPU31
    18. 6.18 CPU32
    19. 6.19 CPU33
    20. 6.20 CPU34
    21. 6.21 CPU35
    22. 6.22 CPU39
    23. 6.23 CPU40
    24. 6.24 CPU46
    25. 6.25 CPU47
    26. 6.26 DMA4
    27. 6.27 DMA7
    28. 6.28 DMA8
    29. 6.29 DMA10
    30. 6.30 EEM8
    31. 6.31 EEM9
    32. 6.32 EEM11
    33. 6.33 EEM13
    34. 6.34 EEM14
    35. 6.35 EEM16
    36. 6.36 EEM17
    37. 6.37 EEM19
    38. 6.38 EEM23
    39. 6.39 FLASH29
    40. 6.40 FLASH31
    41. 6.41 FLASH37
    42. 6.42 JTAG20
    43. 6.43 JTAG26
    44. 6.44 JTAG27
    45. 6.45 LCDB1
    46. 6.46 LCDB3
    47. 6.47 LCDB4
    48. 6.48 LCDB5
    49. 6.49 LCDB6
    50. 6.50 MPY1
    51. 6.51 PMAP1
    52. 6.52 PMM8
    53. 6.53 PMM9
    54. 6.54 PMM10
    55. 6.55 PMM11
    56. 6.56 PMM12
    57. 6.57 PMM14
    58. 6.58 PMM15
    59. 6.59 PMM17
    60. 6.60 PMM18
    61. 6.61 PMM20
    62. 6.62 PORT15
    63. 6.63 PORT16
    64. 6.64 PORT17
    65. 6.65 PORT19
    66. 6.66 PORT21
    67. 6.67 RF1A1
    68. 6.68 RF1A2
    69. 6.69 RF1A3
    70. 6.70 RF1A5
    71. 6.71 RF1A6
    72. 6.72 RF1A8
    73. 6.73 RTC3
    74. 6.74 RTC6
    75. 6.75 SYS16
    76. 6.76 TAB23
    77. 6.77 UCS6
    78. 6.78 UCS7
    79. 6.79 UCS9
    80. 6.80 UCS10
    81. 6.81 UCS11
    82. 6.82 USCI26
    83. 6.83 USCI30
    84. 6.84 USCI31
    85. 6.85 USCI34
    86. 6.86 USCI35
    87. 6.87 USCI39
    88. 6.88 USCI40
    89. 6.89 WDG4
  7. 7Revision History

UCS10

UCS Module

Category

Functional

Function

Modulation causes shift in DCO frequency

Description

When the FLL is enabled, the DCO frequency can be tracked automatically by modifying the DCOx and MODx bits. The MODx bits switch between the frequency selected by the DCO bits and the next-higher frequency set by (DCO + 1). The erroneous behavior is seen when the FLL is tracking close to a DCO step boundary and the MOD counter is expected to rollover, but instead the DCO bits increment and the MOD bits decrement. This causes the DCO to shift by up to 12% and remain at an increased frequency until approximately 15 REFCLK cycles have elapsed. The frequency reverts to the expected value immediately afterward.

For example, the modulator moves from DCOx = n and MODx = 31 to DCOx = n + 1
and MODx = 30, causing a large increase in the DCO frequency.

Applications could be impacted as follows:
When using the DCO frequency for asynchronous serial communication and timer operation, the effect can be seen as corrupted data or incorrect timing events.

Workaround

(1) Turn off the FLL.

Or

(2) Implement a Software FLL, comparing the DCO frequency to a known reference such as REFO or LFXT1 using a timer capture and tuning the value of the DCO and MOD bits periodically.

Or

(3) Execute the following sequence in periodic intervals.

1. Disable peripherals sourced by the DCO such as UART and Timer.

2. Turn on the FLL.

3. Wait the worst case settling time of 32 X 32 X fFLLREFCLK to allow it to lock to the target frequency.

4. Turn off the FLL.

5. Compare the DCO frequency to a known reference such as REFO or LFXT1 using a timer capture.

- If the DCO frequency is higher than expected, repeat from step (2) until the frequency reaches to the expected range.

- Else proceed with code execution.

See the application report UCS10 Guidance SLAA489  for more detailed information regarding working with this erratum. This erratum does not affect proper operation of the CPU when MCLK = DCO/FLL and is set to the maximum clock frequency specified in the device datasheet.