9 Nov
2015
9 Nov
'15
12:57 p.m.
On Nov 9, 2015, at 12:26 PM, Eric Smith <spacewar
at gmail.com> wrote:
On Thu, Nov 5, 2015 at 8:18 PM, Guy Sotomayor <ggs at shiresoft.com> wrote:
Yes.
* The expansion bus in the IBM PC was the same
bus as the System/23. The
connector was rotated 180* so that some of the less expensive
cards from the PC couldn't be used in the System/23. The other
reason for this was since the IBM PC was done on a "shoe string"
budget, they could take the System/23 cards and only had to do some
minimal re-layout of the board.
Did the System/23 also use edge-triggered interrupts, rather than level?
Do you have any idea why it was thought a good idea to use
edge-triggered interrupts?
I wasn?t really involved in the HW side of things but I think it was because it was
?easier?. I think at least one device just generated a pulse for an interrupt rather
than having some sort of latch.
TTFN - Guy