Deframing data within SDLC frames for data logging

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If anyone is familiar with IBM's ancient SDLC standard, I am doing a research project to log data contained within SDLC frames. It's somewhat of a custom SDLC implementation. There is only one data channel, the data is FSK modulated, and fed into an FSK demodulator with a TTL level output in NRZI line coding, and fed into a microcontroller with an SDLC transceiver. The microcontroller handles the SDLC address, deframes the data and sends it off to the parallel bus. It's how data is fed into the Weatherstar 4000, and my goal is to eventually figure out a way to feed data into the Weatherstar 4000 without the satellite feed. What I want to do now is to figure out how to log the raw, deframed data so I can analyze it and figure out it's format.

Would anyone be of help? I know there are drivers for old SDLC ISA cards in the Linux kernel. Would anyone be able to offer any insight on this?

Thanks.

So do you need to get the data to a PC to capture and be able to analyse?
SDLC is the precursor to HDLC apparently and HDLC sounds very much the same with the NRZI encoding. HDLC is the framing used on Cisco router serial interfaces. You could get a Cisco router (the old ones like 2500s with Serial interfaces are cheap as chips 2nd hand), configure the Serial interface with IP, and use that as transport to get the data to a PC via the routers Ethernet interface maybe?

I was thinking exactly that. I've seen SDLC configurations for Cisco hardware, and even have the async/sync WIC. The configs talk about transporting SDLC over IP, so I might be able to do that and log the data with netcat or something. I just wonder if it'll work as we described.

Yeah grab it all using TCPdump or something. Then you have to extract the data, for that you will have to write an application of some sort.
I'm missing something I'm sure..the data will have to have a UDP/TCP header, for which the SDLC contents needs to be interpreted as 'something' on the router, i.e. an application layer belonging to the data..thats where my knowledge runs out a bit, how you'd do that
Interesting project