20 Nov
2007
20 Nov
'07
7:34 p.m.
I'd like to see an 80286 to 80486 upgrade card. It
would need to somehow
I have one. It's currently running in the machine I am typing this on.
It's a little module with a TI 486-compatile processor on one side and,
IIRC, the floating poiut coprocessor for it on the other (or at least
that's the only explanation I can find for 2 large PQFPs). A couple of
PLDs and a PLCC 'plug' to go into the 80286 socket. It's not an ISA card
or anyhting like that, it just goes into the processor socekt. Packed
with it was a PLCC socket, the idea being you could plug that into the
PGA socket of that type of 80286, then plug the module on top. Doing that
clashed with one of the expansion cards in this PC/AT, so I desoldered
the PGA socket, soldered a PLCC socket in its place, and stuck the module in.
I think I looked up the processor chip in a databook once to find it was
actually designed for laptops, and could run iwth a 16 bit external bus.
Which simplified things a lot.
-tony