Why do you need a network stack? Send the data over an RS-422 connection with the RX lines physically disconnected. Send a sequence number and checksum with eac

Why do you need a network stack? Send the data over an RS-422 connection with the RX lines physically disconnected. Send a sequence number and checksum with each transmission so data loss and corruption can be detected, and store a local copy of everything you send, so that it can be retrieved manually if something went wrong with the transmission (which is unlikely, because RS-422 is simple and reliable).