• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 1 answer
  • Subscribers 30 subscribers
  • Views 123 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TMS570LC4357: VCLKACON1 109h

Sebastian Sokolowski1
Prodigy 100 points
Part Number: TMS570LC4357
Other Parts Discussed in Thread: HALCOGEN,

Hello,

In spnu563a.pdf document, I found information that reserved bits 15-0 in VCLKACON1 should return 0x0109 value. After register reading, I fund value 0x0009. Is this just a bug in documentation or should I expect different register values depending on silicon revision? Or maybe under some other conditions? I'm asking about it as currently, I'm working on a project which requires register validation using read.

Thank you for help,

Regards,

Sebastian Sokołowski

  • +1
    TI__Guru**** 192486 points

    Hi Sebastian,

    It is 0x109. But it doesn't matter because this async peripheral clock is not used in this device. 

    Sebastian Sokolowski1 said:
    should I expect different register values depending on silicon revision?

    Both RevA and RevB return 0x109. 

  • 0 in reply to QJ Wang
    Prodigy 100 points

    Thank you for the information. I assumed that this field is not possible to be modified but it seems that write operation and value change is accepted. The code which was changing this value was generated by HALCOGEN.

    Regards,
    Sebastian Sokołowski

  • 0 in reply to Sebastian Sokolowski1
    TI__Guru**** 192486 points

    In several Hercules devices, for example RM48L852, the VCLKA3 is used to clock USB modules (host and device). The bits 15-0 in VCLKACON1 configures the VCLKA3. The bit 11-8 is the clock divider, bit 3-0 defines the VCLKA3 clock source (9 indicates VCLK)

    0x109 --> VCLKA3 = VCLK/2

    0x009 -> VCLKA3 = VCLK/1

    The TMS570LC4357 doesn't support USB host and device, and the VCLKA3 is not implemented. Writing value to bit[15:0] of VCLKACON1 doesn't matter at all.