I haven't been able to find any reference to this info on uCapps.de and the forum so it's reference info for anyone who wants to connect an external SD card socket and ENC28J60 based ethernet board at the same time. Both of these devices are connected to the core with SPI. While I have been try to get them both to work at the same time I have learnt that SPI can be connected in two ways, "Star" and "Chain". The SD card socket and ethernet module need to connected in a "Star" configuration in