I meant the 1020 card with discrete TTL. Although there is that EPROM, which is apparently used in the datapath somehow (some kind of LUT for encoding/decoding?). Interesting aspect of the card is that it seems to be purely interrupt and DMA driven, as it has entire address bus left unconnected. I suspect that there is some clever abuse of i8237 DMA controller involved, which would explain the compatibility issues.
EPROM stored codes for controlling video recorder - the card has IR receiver and blaster, you record t-e codes from remote voa receiver, then the card controls the recorder.
It is an EPROM (apparently 8x8KB 2764 in particular), EPROMs are not really intended to be in system (re-)programmed, so storing the IR codes in it does not really make sense. Proximity of pair of ALS193 to that EPROM makes me thing that it contains data for some kind of fixed pattern (by rough approximation the 64kbits work out quite neatly to the horizontal resolution of the "Arvid 1020" text on the spacer pattern shown in the article).
[Edit: alternatively it is possible that the EPROM contains some kind of "microcode" that serves as sequencer for rest of the circuitry, which is probably more likely]
Another interesting things are the 4 wide DIPs at the bottom edge of the card, these are clones of AM29705, which is 16x4bit dual port SRAM, apparently this serves as some kind of minimal buffer between whatever the rest of the card is doing and the DMA activity. As there is no IO except DMA I suspect that the card continually samples input and produces output, probably with the IR input and output being interleaved into the "video" data in some way (as one of the 16 bits?).
