SLAZ348AF October   2012  – May 2021 MSP430F6735

 

  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  AUXPMM1
    5. 6.5  AUXPMM2
    6. 6.6  BSL7
    7. 6.7  BSL14
    8. 6.8  CPU21
    9. 6.9  CPU22
    10. 6.10 CPU36
    11. 6.11 CPU40
    12. 6.12 CPU46
    13. 6.13 CPU47
    14. 6.14 DMA4
    15. 6.15 DMA7
    16. 6.16 DMA9
    17. 6.17 DMA10
    18. 6.18 EEM8
    19. 6.19 EEM17
    20. 6.20 EEM19
    21. 6.21 EEM23
    22. 6.22 JTAG26
    23. 6.23 JTAG27
    24. 6.24 LCDB5
    25. 6.25 LCDB6
    26. 6.26 PMM7
    27. 6.27 PMM11
    28. 6.28 PMM12
    29. 6.29 PMM14
    30. 6.30 PMM15
    31. 6.31 PMM18
    32. 6.32 PMM20
    33. 6.33 PMM26
    34. 6.34 PORT15
    35. 6.35 PORT19
    36. 6.36 SD3
    37. 6.37 UCS11
    38. 6.38 USCI36
    39. 6.39 USCI37
    40. 6.40 USCI41
    41. 6.41 USCI42
    42. 6.42 USCI47
    43. 6.43 USCI50
  7. 7Revision History

6.18 EEM8

EEM Module

Category

Debug

Function

Debugger stops responding when using the DMA

Description

In repeated transfer mode, the DMA automatically reloads the size counter (DMAxSZ) once a transfer is complete and immediately continues to execute the next transfer unless the DMA Enable bit (DMAEN) has been previously cleared. In burst-block transfer mode, DMA block transfers are interleaved with CPU activity 80/20% - of ten CPU cycles, eight are allocated to a block transfer and two are allocated for the CPU.

Because the JTAG system must wait for the CPU bus to be clear to halt the device, it can only do so when two conditions are met:
- Three clock cycles after any DMA transfer, the DMA is no longer requesting the bus.
and
- The CPU is not requesting the bus.

Therefore, if the DMA is configured to operate in the repeat burst-block transfer mode, and a breakpoint is set between the line of code that triggers the DMA transfers and the line that clears the DMAEN bit, the DMA always requests the bus and the JTAG system never gains control of the device.

Workaround

When operating the DMA in repeat burst-block transfer mode, set breakpoint(s) only when the DMA transfers are not active (before the start or after the end of the DMA transfers).