[Coco] Proto CoCo

[Gene Heskett]

On Monday 28 August 2006 14:34, Roger Merchberger wrote:
>Rumor has it that Gene Heskett may have mentioned these words:
>>I can do the routing on my cnc micromill.  That shouldn't be more than
>> 30 lines of gcode to hand carve a working approximation of that edge
>> profile.
>
>That's one of the main things that's been stopping me from a pet project
> I started about 5 years ago... The other thing was drilling *all* those
> holes for a fair amount of TTL to do the buffering/latching/address
> decoding for.
>
>>But I'm also partial to having the address decodeing and buffered bus
>> stuff all present and accounted for.
>
>Which is what I had started implementing...
>
>>   Ditto OC buffers for all the IRQ related
>>stuff so we don't see the IRQ's blinking the video slightly since
>> there's way too many pullups using way too low R's in the average
>> lashup.
>
>This is what I'm less knowledgeable about.
>
>=-=-=
>
>What I'd originally wanted to design/build was a buffered bus "companion"
> - with a ROM socket, integrated latched I/O, *full* address decoding for
> several addresses, a small breadboard, and pin headers for wire-wrap
> access to the bus signals... and if I got way overproductive, maybe some
> built-in A/D\D/A to boot. Basically the "ultimate" hacker/experimenter
> board for the CoCo.
>
>However, the board space for all the 6-bit/8-bit buffers & latches
> started taking up quite a bit of board space.
>
>Now that the 16-bit buffer chips are out (and in surface-mount) (and I
> have access to some on some spare boards) the board would be much easier
> (read: less drilling) to build with a lot less board real estate
> consumed just for the primary support chips.
>
>I also wanted to put the address decoding I felt was necessary into a
>PAL/GAL instead of diddling with individual AND/OR/NOR gates, but I'm
>obviously not smart enough to understand those critters; as there's no
> such thing as a "PALs/GALs for Dummies" book yet. I guess there's a
> reason for that. ;-)
>
>I think I still have all the files WRT my project (and I even think I
> have the original (not complete) board artwork (done in AutoCad - it's
> all I know ;-) *somewhere*...
>
>If I wasn't going 7:30 am -> 3:00 am maybe I'd have time to restart the
>project again... ;-)
>
>BTW, is there any good all-around circuit software for Linux - *but* not
> a standard Linux distro? PCB compiled fine on my Linux From Scratch
> machine, but gEDA barfed horribly last time I tried to build it - in
> such a way that it confused me no end (no surprise there) and I gave up
> on it. I'd consider any halfway decent package, good libraries a plus
> but certainly not necessary (but bonus points to software that's
> especially easy to *make* part libraries).
>
>Laterz,
>Roger "Merch" Merchberger

I have geda, probably a year old and out of date installed on this FC2 box, 
Roger, but haven't had the round tuit (like you) to actually make it do 
anything usefull yet.  The install at the time wasn't a bit problematic.

>--
>Roger "Merch" Merchberger   | Anarchy doesn't scale well. -- Me
>zmerch at 30below.com.         |
>SysAdmin, Iceberg Computers

-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
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message by Gene Heskett are:
Copyright 2006 by Maurice Eugene Heskett, all rights reserved.