WARNING: internal 10|100 PHY requires magjack hardware!

[MarkHaysHarris777]

WARNING:  RK3328 internal 10|100 PHY requires magjack hardware for operation.


The RK3328 internal PHY for the 10|100 ethernet link requires additional hardware to function.  While this is obvious to many of our number, it may not be clear to all of you, including me.

The 10|100 ethernet connection requires not only the internal PHY on the RK3328 chip, but also requires what is called a "magjack"  (the RJ45 connector jack)  which includes a fairly sophisticated isolation transformer "inside" the jack housing !  The magjack is relatively inexpensive and may be obtained from various sources;  the Pine store carries a DAC board for the Rock64 which contains a correct magjack, so if you will be using the DAC the magjack tails along for the ride!

Below I have listed a couple of examples from some suppliers including Sparkfun and Digikey;  as well I have included a sample datasheet so that you can see the internal schematic of a typical magjack. The two that I am highlighting have built-in LED(s) for link and speed which are optional but very handy.

DO NOT  try to wire Rx+ Rx- Tx+ Tx- differential pairs directly to the RK3328 Rock64 board without the isolation transformer found in the magjack !

Magjack from Digikey

Magjack from Sparkfun

Datasheet for the Digikey Magjack

Rock64 DAC with Magjack

Rock64 DAC Schematic (shows magjack connections)

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