EtherCAT slave SPI signal degradation from AR4 stepper drives

[dalethomas81]

If the SPI wires between the EVB-LAN9252-SPI EtherCAT slave board and the Teensy controller in the AR4 are too long, EMI from the stepper drives interrupts the communication and faults out the drive controller.

The current work around is to shorten the wires as much as possible and solder them directly to the pins on the Teensy controller.

Here is an example: