Not clear what you are really trying to do, but if you were to use an AES transceiver (Crystal 8420 etc) this would give you a nice serial output stream with which a bit of logic and a few shift registers could do many things. No DSP needed, but possibly a microcontroller to program the beast.
One approach would be to use a pair of AES transmitter/receiver chips, which allow them to be set and reset. A combined part is the CS8420.
Note that many pieces of equipment do not pass user bits, they tend to get stripped off easily.
