SLAZ305AC October   2012  – May 2021 MSP430F5517

 

  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.      PN80
    3. 5.3 Memory-Mapped Hardware Revision (TLV Structure)
  6. 6Advisory Descriptions
    1. 6.1  BSL6
    2. 6.2  BSL7
    3. 6.3  COMP10
    4. 6.4  CPU21
    5. 6.5  CPU22
    6. 6.6  CPU23
    7. 6.7  CPU26
    8. 6.8  CPU27
    9. 6.9  CPU28
    10. 6.10 CPU29
    11. 6.11 CPU30
    12. 6.12 CPU31
    13. 6.13 CPU32
    14. 6.14 CPU33
    15. 6.15 CPU34
    16. 6.16 CPU35
    17. 6.17 CPU37
    18. 6.18 CPU39
    19. 6.19 CPU40
    20. 6.20 CPU47
    21. 6.21 DMA4
    22. 6.22 DMA7
    23. 6.23 DMA8
    24. 6.24 DMA10
    25. 6.25 EEM9
    26. 6.26 EEM11
    27. 6.27 EEM13
    28. 6.28 EEM14
    29. 6.29 EEM15
    30. 6.30 EEM16
    31. 6.31 EEM17
    32. 6.32 EEM19
    33. 6.33 EEM21
    34. 6.34 EEM23
    35. 6.35 FLASH33
    36. 6.36 FLASH34
    37. 6.37 FLASH35
    38. 6.38 FLASH37
    39. 6.39 JTAG20
    40. 6.40 JTAG26
    41. 6.41 JTAG27
    42. 6.42 MPY1
    43. 6.43 PMAP1
    44. 6.44 PMM9
    45. 6.45 PMM10
    46. 6.46 PMM11
    47. 6.47 PMM12
    48. 6.48 PMM14
    49. 6.49 PMM15
    50. 6.50 PMM17
    51. 6.51 PMM18
    52. 6.52 PMM20
    53. 6.53 PORT15
    54. 6.54 PORT16
    55. 6.55 PORT19
    56. 6.56 PORT24
    57. 6.57 RTC3
    58. 6.58 RTC6
    59. 6.59 SYS10
    60. 6.60 SYS12
    61. 6.61 SYS14
    62. 6.62 SYS16
    63. 6.63 SYS18
    64. 6.64 TAB23
    65. 6.65 USB4
    66. 6.66 USB6
    67. 6.67 USB8
    68. 6.68 USB9
    69. 6.69 USB10
    70. 6.70 USB11
    71. 6.71 USB12
    72. 6.72 USB13
    73. 6.73 USCI26
    74. 6.74 USCI30
    75. 6.75 USCI31
    76. 6.76 USCI34
    77. 6.77 USCI35
    78. 6.78 USCI39
    79. 6.79 USCI40
    80. 6.80 WDG4
  7. 7Revision History

USB8

USB Module

Category

Functional

Function

USB PLL may fail to initialize when DCO is not used

Description

If the DCO is not used or does not source any clock in the system, the PLL may not initialize properly, leading to a "bus error" NMI when the CPU attempts to access USB memory. Under certain conditions, the PLL requires the DCO to be active in order to initialize properly. If any of the system clocks (MCLK, SMCLK, ACLK) are derived from the DCO during PLL initialization, this condition is satisfied and the PLL initializes in a stable manner.

Workaround

- Configure one of the system clocks to use the DCO for normal operation.  (In most applications, it's convenient to source MCLK from the DCO.)

or

- If it's necessary to use a clock configuration that doesn't include the DCO, then briefly activate it, then de-activate it.  This should be done after setting the UPLLEN bit but before polling the USBPLLIR flags.  The code below shows a simplified PLL initialization procedure.  (In the MSP430 USB API Stacks, this is performed in USB_enable().)  

    USBPLLCTL |= UPLLEN;    // Enable PLL

    // Add the following code to enable the DCO, then immediately revert back
    // to the original clock settings for the application.  This is long
    // enough to allow PLL initialization to proceed.  The actual UCSCTL4
    // settings depend on the application's clock requirements.  

    UCSCTL4 = SELA__REFOCLK + SELS__XT2CLK + SELM__DCOCLK;  // Enable the DCO
    UCSCTL4 = SELA__REFOCLK + SELS__XT2CLK + SELM__XT2CLK;  // Revert back

    //Wait for the PLL to settle
    do {
        USBPLLIR    =     0x0000;  // Clear the flags
        for (i =0; i < 400; i++);  // Wait for flags to set if not stable yet
    }while (USBPLLIR != 0);

    // PLL is now stable