[Coco] make-do ROM Paks

[Roger Taylor]

At 03:16 PM 9/16/2007, you wrote:

>If you end up needing to get a 'mess of boards' made, why not just 
>go with a design that uses a 28-pin socket to accept 
>2764/27128/27256/27512 EPROMS?  I have already created a prototype 
>layout for such a board using the ExpressPCB software. I can send 
>you the layout file if you like. You can view an image of the layout at:
>
>http://www.coco3.com/users/DarrenA/CoCoPak.gif

That's what I was saying ... a mess of boards that use the 2764.  I 
looked at your design the other day for a few minutes.  Before I can 
submit something similar to a company to etch I will have to know 
that it will fit a CoCo port accurately.  Ofcourse, I'm not doubting 
your hard work.  It's probably ready to go as-is... ?  I know it can 
be very hard to insert and remove a case-less card in the CoCo if it 
is brand new or a certain thickness.  My J & M controller to this day 
is very tight fitting in an MPI or CoCo.  I tried it without the case 
earlier and I had to wiggle the board, etc.  Doing all of this with a 
tiny board worries me.  Then there's the issue of making cases



>The layout has some jumper pads for configuring the A13 address line 
>and Auto-Start. The board dimensions have been minimized to reduce 
>cost, but it could easily be enlarged or reconfigured so that it 
>could be mounted in a case. The ExpressPCB price quote to have 10 of 
>these boards produced is $97.65 including shipping, 100 boards would 
>be $396.84. These would NOT have gold contacts on the connector.

Auto-start is a must for my project so I wouldn't use that.  I think 
10 boards for proof that they work and to detect minute errors would 
be the best idea, then on to bigger ideas if needed.

I wonder if Mark Marlette would disclose how he had those nice 
SuperIDE cases made, or where.  Then I can compare to the cost of 
having a sheet metal case done.  The J & M controller has a durable 
metal case that looks rather simple to duplicate, although I would 
only go half the length.


-- 
Roger Taylor