• State TI Thinks Resolved
  • Locked Locked
  • Replies 7 replies
  • Answers 1 answer
  • Subscribers 33 subscribers
  • Views 551 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.

TM4C1292NCPDT: Ethernet MAC Peripheral Configuration Register (EMACPC) is Reserved

Danilo A.
Mastermind 28950 points
Part Number: TM4C1292NCPDT
Other Parts Discussed in Thread: TM4C1294NCPDT, TM4C129XNCZAD

Hi Team,

The Ethernet MAC Peripheral Configuration Register (EMACPC) bits of TM4C1292NCPDT are all reserved based on page 1568 of the datasheet. Is there an error in the datasheet?

Regards,

Danilo

  • 0
    Guru 92251 points

    The MSP432E4 SimpleLink™ Microcontrollers Technical Reference Manual defines the contents of the bits in the EMACPC Register.

    I believe the MSP432E devices use the same EMAC module as the TM4C129 devices, so does the MSP432E TRM help to define the register contents?

    The TM4C1292NCPDT datasheet and MSP432E TRM both agree that the reset value for the EMACPC Register is 0x0080040E.

  • 0
    TI__Guru*** 135355 points

    Hello Danilo,

    I think it is an error, and I am seeing if we have a completed version for that exact GPN.

    Hi Chester,

    The TM4C1294NCPDT also has the area filled in and is closer in compatibility, but I think for Ethernet MAC that is on that device, the best to look at would be the TM4C129XNCZAD datasheet as there is MII/RMII functionality for the TM4C1292NCPDT which I think MSP432E4 only has RMII and not MII.

  • 0
    TI__Guru*** 135355 points

    Hello Danilo,

    Ah I was mistaken, that is actually correct to have omitted.

    The EMACPC register is used as a control and status register for the internal PHY. If an external PHY is used as would be done with TM4C1292NCPDT, then the EMACPC cannot be used. To access the external PHY you will need to go through the MDIO interface. See the below mapping regarding how the register maps to the PHY. The bits in the EMACPC are mapped to different internal PHY registers. For external PHY this mapping cannot be established. You could have an external PHY from a third party vendor that the EMACPC has no idea on how to properly interface with it.

  • 0 in reply to Ralph Jacobi
    Prodigy 20 points

    Hi,

    if the EMACPC register should be omitted, how can I configure the MAC to use RMII or MII interface with the PHY? If it should be omitted, why in chapter 20.4 (Initialization and Configuration) point 2 is said: "Select the RMII interface by programming the PINTFSbit field to 0x4 in the Ethernet Peripheral Configuration (EMACPC) register at offset 0xFC4". How can I do that?

  • 0 in reply to Petr Sulima
    TI__Guru**** 191886 points

    Hi,

      Sorry for the confusion. When external PHY is used, only those bit fields (i.e. PHYEXT, PINTFS) that have no corresponding internal PHY register mappings (the table listed by Ralph in the last reply) are meaningful. 

  • 0 in reply to Charles Tsai
    TI__Guru*** 135355 points

    Hi Charles,

    Thanks for helping explain this further. Would the TM4C129XNCZAD datasheet be the best one to refer to in order to see the details for those bits since the TM4C1292NCPDT datasheet have all bits listed as reserved for EMACPC?

  • 0 in reply to Ralph Jacobi
    TI__Guru**** 191886 points

    Hi Ralph,

      Yes, the TM4C129XNCZAD datasheet would have the details for PHYEXT and PINTFS in the EMACPC register.