• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 33 subscribers
  • Views 357 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

Linux/DS125DF410: CDR status, register 0x02

nakanishi
Prodigy 30 points
Part Number: DS125DF410

Tool/software: Linux

Hi Team, I have a question on DS125DF410 CDR status.

I use this IC with no adaptation mode, and Bits 6:5 register 0x31 are set 00.

And Bit 6 register 0x02,sometimes shows 0 that means CTLE auto-adaptation in progress.

Is it not problem?

Please let us know.

Thank you. 

 

  • 0
    TI__Guru* 93670 points

    Greetings,

    When operating in AM0 or adapt mode 0 - reg 0x31[6:5]=1'b00 - this means there is no auto adaptation. The user through register has to set CTLE or EQ boost values. EQ boost is set through registers 0x3A and 0x03. There is a good explanation of this mode of operation and how to set up CTLE register in DS125DF410 data sheet section 7.5.8. Please refer to this paragraph for details. Also, please note once CTLE is set correctly device would lock and reg 0x02[5:4] = 1'b11 - indicating a CDR lock condition.

    Regards,,nasser

  • 0 in reply to Nasser Mohammadi
    Prodigy 30 points
    Hi Nasser,

    The CTLE setting is as per data sheet section 7.5.8.
    Is the selected EQ boost value incorrect when reg 0x02[5:4] = 0'b11?

    Thanks,
  • 0 in reply to nakanishi
    TI__Guru* 93670 points
    Greetings,

    If reg 0x02[5:4]=0'b11 it means device is locked and CTLE setting is correct.

    Please read reg 0x27 and reg 0x28 when CDR is locked. These indicate eye opening both in horizontal and vertical domain. You should set your CTLE in such a way to optimize or maximize contents of these two registers.

    Regards,,nasser