At Commodore they call this an "user port". You would need some PEEK() / POKE equivalent for Lisa Pascal, that's all.
Apple used to use their own machines as end of line production test equipment. This board might have been used in that context.
Yes, as a Commodore kid, I know exactly what you mean.
I've seen them on pets, vic20's, c64's, and c128's.
So there actually is another Lisatest card up on ebay, but this one is damaged, it's supposed to have large power resistors at the top and a ROM in the socket. It's $150 now, but it's incomplete. The same seller had a complete one that was sold much earlier on. If you one you picked it up perhaps you could dump its ROM.
What's interesting is that I've noticed about the Test card (not this guy) is that it has an ADC chip at the top right under the resistors. So they used this to measure voltages (or perhaps watts) in the card as a proxy to test the power supply.
There's also a COP421 controller attached possibly to one of the VIA6522's and the other one goes to a DB25. There's also a DB9? not sure what these were for but likely to communicate with external test equipment. I'd imagine that they could boot off the test card rather than have to insert a LisaTest floppy, but that's conjecture.
Possibly one VIA allows the Lisa's CPU to talk to the COP to test the slot. Maybe the COP sent some bytes back and forth through that VIA to the Lisa to test the slot. The external VIA was likely used to talk to whatever the factory floor umbilical cord had to pass/fail and maybe upload a copy of LisaTest to that Lisa's RAM.
(I'm guessing here.)
I don't think this specific prototype card was used in factory line QC testing, I think it was really a prototype for an early parallel port expansion though it may have grown into that later on.
