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Altera_Forum's avatar
Altera_Forum
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10 years ago

SWAP EMAC TX RX bits ( MAC <-> PHY )

Hi Everyone,

I'm working on a custom board that assembly with Arria5.

Due to layout PCB issue on my custom board I want to swap between RGMii TX bits --> TXD3 with TXD0 & TXD1 with TXD2

and also same wsap needed on the RX bits ( RXD3 with RXD0 & RXD1 with RXD2 ).

Is it possible to modffied Uboot EMAC driver ? i don't fmiliar with the EMAC driver and i understood that this can't be done at the QSYS muxing.

please advise,

Thanks in advance,

Moran.

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    10 years ago

    Can't you just change the FPGA pin mapping in your project to match the PCB?

  • Altera_Forum's avatar
    Altera_Forum
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    10 years ago

    --- Quote Start ---

    Can't you just change the FPGA pin mapping in your project to match the PCB?

    --- Quote End ---

    I think we're talking about the HPS EMAC, which is on dedicated pins through the pinmux.

    I'd think there is a way to do this by running the EMAC pins to the FPGA, and then back up to the HPS using LoanIO. Then you'd have the pins in the correct place and can rewire them in the FPGA...You might need some management logic, though, and need to use some adaptors in Qsys to turn MII into RGMII?