[Coco] Multi Pack Replacement

[Al Hartman]

1. I think anything other than a simple MPI Clone is a project way beyond 
the scope of hobbyists. It sounds so simple to say, "hey! Let's throw this 
or that in!" When you aren't the one who has to design, debug, and produce 
it.

At Zebra Systems, we sold a disk system for the Timex Computer made for the 
ZX-Spectrum and the TC-2068. The TC-2068 was software compatible with the 
American TS-2068, but the expansion bus had a ZX-Spectrum pinout rather than 
the one the American system had. We had to manufacture something called a 
Twister Board. I was pushing for us to make a "Super Twister" which would 
have the expansion adapter, RGB video out, and an on-board Spectrum Emulator 
ROM. We even had the thing already designed for us in the technical manual 
Timex published.

We wasted half a year laying out, building and testing prototypes to give 
up. It was taking too long and costing too much to develop. We'd never earn 
it back in sales. We laid out a simple twister that worked first time, and 
went into production with those.

Things that seem easy to just throw in, add more complexity than a layman 
understands. There are power requirements, noise in the circuitry, software 
drivers, testing, debugging built boards which as the complexity rises, so 
does the likelihood of a mistake in the build up.

Simple is better. Trust me. Why do you think none of the other projects ever 
got built?

2. I would not want to use my Coco lifted up into the air several inches. I 
think the best way to do this is to use the buffered cable so the MPI could 
go behind the Coco, or off to the side. To put carts horizontal rather than 
vertical means that bracing will definitely be necessary for the board, as 
there will be more stress on it. A board in the same orientation as the 
original needs a simple case. Two sheets of plexi (like the CocoSDC case) 
with the top piece having slots milled or laser cut out for the cartridges.

My advice is to K.I.S.S. - Keep it simple stupid.

-[ Al ]-