• State Resolved
  • Locked Locked
  • Replies 13 replies
  • Answers 1 answer
  • Subscribers 32 subscribers
  • Views 2791 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.

TPS65982: The register indicating eMarker cable connection

Takashi Onawa
Genius 13200 points
Part Number: TPS65982

Hi Team,

My customer would like to know if TPS65982 has registers related to eMarker cable connection.

1. Is there a register to detect if the cable supports eMarker?
2. If YES,  Could you tell me which register should be read?

Regards,

Takashi Onawa

  • 0
    TI__Genius 16190 points
    Bit-2 of 0x5F indicate if the cable is active or passive - Please refer Table:3-61 of the Host-interface TRM for details.

    -/Praneet
  • 0 in reply to Praneet Kumar
    TI__Genius 13200 points
    Hi Kumar-san,

    That's very unclear explanation. Let me confirm just in case.

    Is the register asserted by detecting the Emarker IC in the cable?
    Fundamentally, The cables including equalizer or re-timer are called as "Active cable".

    Regards,
    Takashi Onawa
  • 0 in reply to Takashi Onawa
    TI__Genius 16190 points
    Takashi-san,

    If the cable doesn't present Ra, its not eMarked - This can be indicated by Bit-3:1 of 0x1A/Status register.

    If the cable presents Ra, it will respond to SOP' command. 'ProductType' field of the 'Discover Identity' response from the cable will indicate whether the cable is active/passive - TPS65982 will update Bit-2 of 0x5F to reflect this information. Please refer Table:6-29 and Table:C-2 of the USB-PD specification for details on 'ID Header VDO'.

    Let me know if you need additional information.

    -/Praneet
  • 0 in reply to Praneet Kumar
    TI__Genius 16190 points
    Takashi-san, I'm closing this thread - If you have additional queries on the topic, please start a new thread w/ references to the current one for us to track it better.

    -/Praneet
  • 0 in reply to Praneet Kumar
    TI__Genius 13200 points
    Hi Kumar-san,

    Sorry for my slow response on this. Yes, this thread should be closed.
    Thanks for your obviously explanation!

    Regards,
    Takashi Onawa
  • 0 in reply to Takashi Onawa
    TI__Genius 13200 points
    Hi Team,

    May I double check if the answer below is true.
    >If the cable doesn't present Ra, its not eMarked - This can be indicated by Bit-3:1 of 0x1A/Status register.

    My customer thinks it's not correct because there is a cable integrated passive Ra in it, so it can not be said that Ra doesn't correspond to Emarker.

    I think that it should be judged whether there is a response to SOP '.
    Is there a register to detect SOP' timeout in TPS65982?

    Regards,
    Takashi Onawa
  • 0 in reply to Takashi Onawa
    TI__Genius 13200 points
    Hi Team,

    Could you give any comments on this?

    Regards,
    Takashi Onawa
  • 0 in reply to Takashi Onawa
    TI__Genius 13200 points
    Hi Team,

    Could you give any comments on this?

    Regards,
    Takashi Onawa
  • 0 in reply to Takashi Onawa
    TI__Genius 13200 points
    Hi Team,

    Could you give any comments on this?

    Regards,
    Takashi Onawa
  • 0 in reply to Takashi Onawa
    TI__Genius 16190 points
    Takashi San,

    I'm not sure I understand your concern here. What do you mean by the below statement:
    >> "there is a cable integrated passive Ra in it, so it can not be said that Ra doesn't correspond to Emarker"

    As I said in my previous post, if the cable doesn't present Ra, the device will not even communicate with SOP'. If it presents Ra, the device will initiate communication with SOP', and the 'ProductType' field of the 'Discover Identity' response from the cable will indicate whether the cable is active/passive.

    Refer Section-4.9 of the Type-C specification for details on 'Electronically Marked Cables'.

    Thanks & Regards,
    Praneet
  • 0 in reply to Praneet Kumar
    TI__Genius 13200 points
    Hi Praneet-san,

    My customer would like to make sure that the cable which passes compliance test is attached. And in order to surely know the identity of the cable, they think that it is necessary to know the communication result of Cable VDO.

    Is the communication result stored somewhere in the device?

    Regards,
    Takashi Onawa
  • 0 in reply to Takashi Onawa
    TI__Genius 16190 points
    Takashi San,

    My question(s) from the previous post is not yet answered - Hope my response answered the customer's queries.
    0x49 will hold the response 'Discover Identity Response' from SOP' - Refer Page-46 of the TRM document (@ www.ti.com/.../slvuan1a.pdf) for more details.

    -/Praneet
  • 0 in reply to Praneet Kumar
    TI__Genius 13200 points

    Hi Kumar-san,

    Sorry, I forgot to answer your question.

    They want to distinguish bad cables which has built-in dummy Ra but no eMarker IC integrated. they  think that all eMarker cable should expose Ra for Vconn power supply but it's not enough to distinguish such the bad cable because Ra only presents if the cable needs Vconn or not.

    On the other hand, Type-C spec says as followings, so "Discover Identity" response from the cable should be the criterion for judgment.

    "Electronically marked cables shall support USB Power Delivery Structured VDM Discover Identity command directed to SOP’."

    Anyway, I could get the Cable VDO information from RX Identify SOPp register(0x49) as below.
    Thanks for your support.

    Regards,

    Takashi Onawa