This is the client node. Three servo outputs, five mosfet outputs, serial out for sound card (up to 4 channels), serial in for RFID reader. Two inputs left over for speed sensor and/or current sensor. If I can come up with the proper code, I can drive DCC out of one of the Mosfets. There is some open source DCC code floating around but I wasn’t impressed with what I saw so that will probably have to be developed from scratch if I decide to.