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TLK110 auto-negotiation and Not auto-negotiation link partner

Other Parts Discussed in Thread: TLK110

Hallo,

TLK110 datasheet mentions below in 3.4 Auto-Negotiation section of 11-page.
“ If the link partner cannot Auto-Negotiate, the TLK110 device enters parallel-detect mode to determine the speed of
the link partner. Parallel-detect mode uses fixed half-duplex mode. “
Does the TLK110 always operate in Half-duplex 100Base, when the TLK110 activates auto-negotiation and the link partner is set in FULL-duplex 100Base (not auto-negotiation)?
By what register can we check the PHY status of the TLK110 above case?

Best Regards,
Kazu Ogawa

  • According to the IEEE 802.3 specification, when a PHY is configured for auto-negotiation and is partnered with a PHY that is not configured for auto-negotiation, the PHY that is not configured for auto-negotiation should be configured for half-duplex.  The situation you describe is a configuration error at the system level.  A PHY should not be forced to full-duplex unless the link partner is configured to link in full-duplex. 

    Patrick

  • Patrick-san,Thank you very much for your reply.The customer reports to me
    ---------------------------------------------------------------------------------------------.
    TLK110 Auto-Negotiation < ----------------------------------- Link partner (PC) Forced mode
    PHYSTS (0x0010) register read below
    0x0315 (100BASE Full duplex) < --------------------------- 100BASE Full duplex Forced mode
    0x0117 (10BASE Full duplex) < ----------------------------- 10BASE Full duplex Forced mode
    ---------------------------------------------------------------------------------------------
    Why isn’t PHYSTS read “ Half duplex “?Is this system level error?
    Isn’t it correct the register he should read?Best Regards,Kazu Ogawa
  • Hi Kazu,

    What does register 0x000A bit[5] read?
    This register allows for forced full-duplex mode when set to '1'.

    Regards,
    Ross
  • Ross-san,

    Thank you very much for your reply.

    I will ask the customer to check it.

    Best Regards,

    Kazu Ogawa