Ignore RMII_RXER

Christian Fuchs1

Other Parts Discussed in Thread: TMS570LS3137, HALCOGEN

Hello.

I'm using a TMS570LS3137 with a Micrel KSZ8895RQI attached over RMII. I've already learned that the RMII_RXER line is optional, and so I want to use this pin (N19) as GPIO for a chip select line. This line is most of the time high and I can't get a connection. If I set it to low permanently the connection is working.

I've used HalCoGen 03.06.00 Pinmux to set this pin to AD1EVT function.

Is there a chance to use it this way? Can the MAC in the TMS570LS3137 ignore the RMII_RXER pin?

Best Regards

Christian

over 10 years ago

0 Biser Gatchev-XID over 10 years ago

TI__Guru**** 393215 points

Moving this to the TMS570 forum.

0 Chuck Davenport over 10 years ago

TI__Guru 59540 points

Hi Christian,

Theoretically this might be possible, but I think there are some nuances to the pinmux design that might impact the feasability. I have forwarded your post to one of our TMS570LS3137 experts for them to evaluate your question and provide some guidance. They should get back to you soon.

0 Sunil Oak over 10 years ago in reply to Chuck Davenport

TI__Mastermind 49120 points

Hi Christian,

The RXER input to the EMAC is not optional. If the Micrel PHY does not drive this input to the MCU, then it must be grounded externally. That is, you will not be able to use it as a general-purpose I/O.

Regards,
Sunil

Arm-based microcontrollers

Arm-based microcontrollers forum

Ignore RMII_RXER