DP83848I: MDIO/MDC required?

Alex Suarez

Part Number: DP83848I

I am using the DP83848IVX/NOPB chip for converting RMII to Eth, however I am unable to use the MDIO and MDC ports on my MCU. Is MDIO and MDC necessary for this conversion function of the chip? I have the 1K5 pullup resistor for MDIO, is there anything else I should do to wire this for use without the MDIO/MDC functionality?

over 3 years ago

0 Alon Kopelman over 3 years ago

TI__Expert 3727 points

Hi Alex,

I see that the Datasheet calls for a 2.2k resistor for PU and PD. Why do you use 1.5k?

Please look through 'strapping' section of datasheet as there could be other settings you need to adjust. In theory, what you are saying is correct and you do not necessarly need to register write with most desired setups.

Best,

Alon

0 Alex Suarez over 3 years ago in reply to Alon Kopelman

Prodigy 10 points

I used the 1.5k resistor because table 4.3 serial management interface says the MDIO pin 30 needs a 1.5k pullup resistor, I have used the 2.2k for some of the other ports. I will look through the strapping section though.

Thanks,

Alex

0 Alon Kopelman over 3 years ago in reply to Alex Suarez

TI__Expert 3727 points

Hi Alex,

You are correct, understood, let me know if you manage to set the PHY the way you want to using straps, or if there are other configuration questions.

Best,

Alon

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DP83848I: MDIO/MDC required?