Simulating MDIO over GPIO using the TM4C1294KCPDT

Nathan Raggett

Other Parts Discussed in Thread: TM4C1294KCPDT, TM4C1294NCPDT

I'm using the TM4C1294KCPDT to control a network switch chip, however the chip only allows control via MDIO and MDC. Is there a way for me to simply bitbang a method of simulating MDIO in order to access the registers within the switch?

over 9 years ago

0 Amit Ashara over 9 years ago

TI__Guru**** 244400 points

Hello Nathan,

You can use GPIO in bit bang mode to emulate MDIO interface. There is no ready code as this case has never been seen in field. But I would be glad to assist you in building the emulated MDIO interface.

Regards
Amit

0 Nathan Raggett over 9 years ago in reply to Amit Ashara

Prodigy 25 points

Thanks Amit, I've tried bit banging to emulate the method behind how MDIO works, however due to the constraints of my knowledge I get delays in my clock and in my data. I'll PM you some of my code for you to see.

0 Amit Ashara over 9 years ago in reply to Nathan Raggett

TI__Guru**** 244400 points

Hello Nathan,

OK. I will be able to work on it sometime later this week only.

Regards
Amit

0 Kushal Patel over 9 years ago in reply to Amit Ashara

Prodigy 10 points

Hello Amit,

I am facing the same issue. I can't read the Ethernet switch registers using bit banging for simulating MDIO/MDC.
I am using Tiva TM4C1294NCPDT in our product.

Does TI or you have any ready code for the same?

Thanks & regards,
Kushal Patel

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Simulating MDIO over GPIO using the TM4C1294KCPDT