This morning's vid during breakfast:
Which does bring back memories; my primary computer back in college was a more modern version of that, built around a 6809 CPU. Someday, when I have a bunch of time on my hands and some uncluttered workbench space, I'll have to dig that out and make a vid about it. It bridged the 6502 and 68000 eras....
Anyway. This got me thinking of the various MC68xx peripheral chips of the era, and a question that had arisen back around maybe 2010-ish: someone who was making highly-specialized industrial equipment had been using the MC68488 HP-IB controller, which had gotten to be in short supply, and was looking for alternatives. (I think he ended up redesigning his controller entirely.)
A reasonable solution might have been to re-implement the 68488 functions in a small FPGA, or even a CPLD; for a drop-in replacement, this would have to go on a little board with a 40-pin DIP footprint, presumably including level shifters and a voltage regulator so's a modern 3.3V programmable logic device could plug into a 5V system.
Now, my fuzzy little morning brain having been tickled, I'm thinking that a modern MCU would quite capable of bit-banging both the HP-IB signals and the 6800 system bus, though maybe not both at the same time. But! This might be something that an RP2040 could handle, what with the two CPU cores and the PIO features. I think the PIO could handle HP-IB; could it also do a 6800 bus slave?
... Not that I think anyone is really looking for a drop-in replacement for that particular chip just at the moment, so this is kind of a solution in search of a problem, but it's one of those interesting ponderments.
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