At SELEM I was lucky enough to purchase a unit and a collection of video tapes. The video tapes contain laser show data, the unit decodes (and two encoders) the data from the tape and turns it into galvo, color and shutter controls for two projectors.
So far I've figured out the DACs, sort of where they get their chip enable from, and how the memory is tied to the DACs. I don't yet know how the data gets serialized into the memory or what triggers the chip select/write state for the DACs.
But anyways, I made a ~14 minute video of my progress so far:
https://www.youtube.com/watch?v=OLTajuHGd54
I'll probably get my Beta and editing VHS deck from Norfolk this weekend as well as SGI Octane workstation which has lightpipe in and out, and firewire bridge(s).
My goal is to convert direct-digital the data from the tape to computer then convert that into WAV or PCM audio that can be played back on ADATs, sound card setups and more.
I also plan to capture the data videos to MPEG2-TS.
I've also talked to a friend about trying to make a utility that can play wav files straight to RIYA and Etherdream DACs over USB and ethernet (And maybe the OpenLase ardunio shield as well!?)