IBM System/32 available
Guy Sotomayor
ggs at shiresoft.com
Mon Nov 9 14:57:21 CST 2015
> 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:
>> * 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?
Yes.
>
> 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
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