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rcm6700 ethernet with transformerless

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We want to connect the ethernet port on RCM6700 to the switch chip and we want a design without transformer.

We want to connect directly, the RCM6700 ethernet port to one port on switch

Any hardware application?

Also we would need to disable the AUTO-MIDX, how can we do it?


Jose Luis
asked May 20, 2019 in Rabbit Software by jlrubio New to the Community (7 points)

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1 Answer

0 votes
The RCM6710 and RCM6760 have the transformer and Ethernet jack, but the RCM6700 and RCM6750 do not.

As you can see from the schematic, those modules put TX+/TX- and RX+/RX- on the header. What signals does the switch chip expect?


And the schematic for the development board shows taking those signals directly into an Ethernet jack with integrated magnetics:


To disable auto MDIX, it looks like you can define DMAETH100_PXDR_AMDIX_EN as 0 in your project macros.
answered May 23, 2019 by TomCollins Veteran of the Digi Community (2,297 points)
Thanks for your answer.

I am going to try explain better!!!

we want to connect two PHY (RCM6700 and other manufacture PHY) without magnetics.

We would like to know if we could connect directly TX+/TX- and RX+/RX- between both PHYs or we would need any passive components (resistors, capacitors, etc)

Jose Luis
I'm not sure if that would work or not.  I'd recommend searching elsewhere for a solution.  This question on the Electronics StackExchange has some good information, but it doesn't sound easy: https://electronics.stackexchange.com/q/90330