What are these signals from ADTJA1101-RMII board utp cables

[ssattva1]

We are trying to implement the lwip stack on S32K3X8EVB-Q289 evb, connected to ADTJA1101 - RMII phy eval board via SABRE connector . However , upon turning the power on, we were able to observe signals from the UTP cables of the PHY eval board without even flashing the code. I get it that the board is in AUTO_OP mode. However , the board is in slave mode, so I presume that it shouldn't initiate any communication. Then what are these signals , what is their purpose?

[PetrS]

Hi,

it could belongs to Link Startup and Handshake process. Upon power-up, the master and slave initiate a handshaking process to establish the link, called the link startup or link training process.

BR, Petr