I've got the Techrefs in front of me (PC, and
PC/XT)
The PC motherboard schematics show that all 5 expansion slots are wired
in parallel. There's nothing odd about any of them.
H'm. I use third-party books. Suppose if I wrote the author they'd put out
an updated edition?
The schematics for both versions of the XT motherboard (64K-256K and
<Snip>
FWIW, I've
run a variety of cards in XT slot 8 and PC slot 5 with no
problems.
On clones, sure. But I have a genuine IBM PC/XT on my desk and the
built-from-a-kit 8255 card wouldn't work in slot 8 without a little extra
logic (which I made from unused gates on the card).
Nope. Real true-blues. Maybe it gets more tolerant with time?
manney