• State
  • Locked Locked
  • Replies 2 replies
  • Subscribers 101 subscribers
  • Views 817 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.

TMS320C6748: How to test USB eye diagram in full speed mode

Tony Tang
Mastermind 25216 points
Part Number: TMS320C6748

The TRM told how to test eye diagram in high speed mode, but how to do that in full speed mode?

  • 0
    TI__Guru**** 161600 points
    Hi,

    I've notified the factory team. Their feedback will be posted here.

    Best Regards,
    Yordan
  • 0
    TI__Guru* 78325 points

    Hi Tony

    Sorry for the delay, i talked to the USB experts 

    The eye diagram test setup can be found 

    The USB Standard: Full and Low Speed Compliance Test Procedure. (Fig B-7) 

    If the USB2.0 is used in device mode You need to place a full speed hub between the PC and 6748, and this full speed hub will force DSP into full speed mode.

    If you are testing host mode, you will connect a FS device to processor  and capture the SOF packet for the eye diagram.

    In general, we've never seen a FS/LS EYE test failure when HS passes. It would require that the controller itself be faulty…if the PCB is good enough to pass HS EYE, it's more than good enough for FS/LS.

    Hope this helps.

    Regards

    Mukul