The connections between RJ45 and ADIN1300 MDIO

Hello,

Apologies for slow response, can you please share more of the schematic? and details on how you have the PHY configured?

Can you also share the part number for the RJ45> 

thanks in advance,

Catherine.

Hello,
No problem at all, the RJ45 is 7499111446 from würth. so the setup is as following there is a DUT, our main board that has the PHYs and has also Mezzanine connectors, there is also the adapter board which has a female mezzanine connector beside the RJ45. the connections are as following

the setup looks like the following

in which the 4x MDI ethernet pairs are routed from the PHY on the DUT to the connector then over the adapter board to the RJ45. the PHY is set to run with 100Mbit speed.

Hi,

Before diving into the configuration, let's first ensure that the board can establish a proper link. It's possible that the connection between the ADIN1300 and the RJ45 connector isn't solid, which might be causing communication issues with the external PHY.

You won't be able to change the board layout now but you can explore modifying the ethernet cable. Could you hack your Ethernet cable so that it will follow the standard wiring convention between RJ45 connectors? 

Note that you need to skip the write to GE_MAN_MDI_FLIP_CFG bit when doing this experiment. If you're willing to modify your board, it will be better to modify the HW configuration so that the ADIN1300 will not enter SW Power down at power up but instead will try to establish a 100BASE-TX link.  

regards,

Mark

Hello,

What I have already tried is modifying the ethernet pairs externally by conencting the first 2 pairs to the last ones so the end effect is that there's effictively 2x pairs as you can see in the following figure, and that has worked fine totally as expected.