Rumor has it that Tony Duell may have mentioned these words:
I've done this mod (it was described in Rainbow
years ago) to my
Multi-Pak and it works fine...
I've heard it works great when done correctly, but I hadn't had the time to
do that on mine, and I never ran across a problem (yet), anyway... (All I
used with my CoCo3 thus far was a stock floppy controller & a couple of
game carts, but now that my other hardware project is getting closer to
reality, it's probably best to upgrade at least one of my paks before I get
address conflicts...
The older
packs used a (socketted?) PAL for address decoding, and with the
datafile to program a new PAL/GAL it's a drop-in replacement.
AFAIK it should be possible to use the deadbug mod with an older-type
Mulit-Pak. It's not as neat, and it's a bit more work, but 74LS10s are
cheaper than GALs, and you don't need to find the JEDEC file for it. All
the mod does is disable the data buffer in the Multi-Pak so that it
doesn't attempt to drive the data bus during accesses to the extra I/O
registers (part of the GIME chip) in the CoCo 3
Yea, but now that I *have* the programmer, a chip-swap is something that I
might actually have time for...
-- Note -- did you notice I said "have"??? I couldn't believe it - it cost
me $15.28 US for shipping & insurance, requested the cheapest, slowest
shipping available, and it shipped from Santa Clara, CA -- and arrived in
Northern Michigan 24-hours later... (hell, UPS doesn't even guarantee next
day air way up here...)
I was literally cutting & pasting the shipping # to check the shipper
routing (DHL Express) when my friend walked into the back room saying
"Unless this is it..." - he was trying to pull a fast one on me - he new I
was anxious for it - and lo & behold, that was it! :-) :-)
I have yet to see how well it works, but if their attention to shipping &
customer service (the invoice says I have 30 days to replace/trade up & a
90-day warranty - and it's a refurb unit) it can't be all bad for a $200
(shipped) programmer...
I just pulled some EEPROMS from a few junk PeeCee motherboards I can test
it on, and for some GALs -- Jameco, here I come... :-)
Laterz,
Roger "Merch" Merchberger
--
Roger "Merch" Merchberger --- sysadmin, Iceberg Computers
Recycling is good, right??? Ok, so I'll recycle an old .sig.
If at first you don't succeed, nuclear warhead
disarmament should *not* be your first career choice.