30 Aug
2002
30 Aug
'02
8:32 a.m.
On Fri, 30 Aug 2002, Patrick Finnegan wrote:
OK, now I've never gotten to play with one of
these. How exactly does it
hijack the system like this? Does it use some software trick to halt the
motherboard proc, or is there a bus line that lets it grab control, like
the /LOCK line* that's on an 80x86?
Slot 3 on the Apple //e bus is a special slot. Normally, if you have an
80-column card plugged into the special auxiliary slot, you can't use slot
3 for anything else, but the TransWarp is an exception. It was designed
to co-reside with the 80-column card without conflicting, and so takes
advantage of a completely empty (and otherwise useless) slot.
I don't know the actual technical process since I never looked into it,
but in essence I imagine what the TransWarp does is pulls some signal to
let the bus know that it is in control and then takes over that way. I
should dig out my copy of the //e technical reference manual to find out
exactly what's going on.
I imagine it could work in any slot, but I haven't read the documentation
in years, don't know exactly where it is, and don't have the time to
experiment right now :(
Sellam Ismail Vintage Computer Festival
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