Hardware Rev1 Fixes - hampussandberg/HexConnect GitHub Wiki
Connect the crystals to the correct pins, is reversed i rev 1
Remove power relays for UART channels and set 3.3V as default. Add a 5V tolerant buffer on the RX and TX pins to the connector.
Replace relays with mux/DPST analog switch ?
Look for CME0505 replacement -> they have bad spec for low load!
Remove the extra mounting holes?
Supply voltage for CAN isolators on non-isolated side should be 3.3V
V_IO on TJA1051T/3 should be connected to respective isolated voltage as this pin sets the IO voltage. Was disconnected on rev 1. Change to a different CAN transceiver or fix this!