The P8259A-2 is a programmable interrupt controller form Intel, capable of handling eight interrupts. I guess that the use of the switches is probably, enable or disable each one of these interrupts. Maybe this card was used to send signals to other peripherals connected to the machine...
The primary part has a label of P82592 which should make it a LAN controller of some kind. I am not familiar with early network cards and do not recognize this one.
The primary part has a label of P82592 which should make it a LAN controller of some kind. I am not familiar with early network cards and do not recognize this one.
Yeah, I second it's *probably* some kind of network card, although with no markings it's really hard to say what. That chip on it was used both for early "real Ethernet" cards and brand-X "Ethernet-Like" applications. I was going to hazard a guess it might be StarNet, but that usually used six-pin phone-style plugs, not DB cables. Its layout with two opposite-gender plugs makes it look like it was intended for daisy chaining with straight-through male/female cables.
It's also possible this was meant to drive some kind of peripheral using this LAN chip as a "data pump", but that seems like overkill.
It's some sort of specialized networking card. I see a 5V DC-DC block providing current to the external loop and a few optoisolators. Probably a low-speed industrial control NIC.
Looks like every other chip is from a different manufacturer. I see Motorolla, Philips, Intel, Toshiba, TI.
Only 3 wires going to the connectors, and it looks like the two connectors are wired together in parallel.