[Coco] [Color Computer] Multi-Pak Question

[John Eric]

actually, i think the "ghosted" response existed only in the grey 26-3024. the slot select would be addressed at $FF7F and/or $FF9F (FF9F=bad for the CoCo 3). In the large white 26-3024, $FF7F was fully decoded, as it was also in the small white MPI 26-3124. The modded PAL chip for the large MPI's and the sattelite board for the 3124 made sure that the data bus buffer did not activate on addresses larger than $FF7F. Technically, I think it could be modded to extend the range to $FF8F, since, in the CoCo 3 these (FF80-FF8F) were reserved for future expansion, which never happened (the CoCo 3 was the end o' the line). I have made an eagle schematic and board layout for the satellite board which functions just like Tandy's sat board, except instead of cutting the trace from the custom chip to the 74ls245, you socket the 74ls245 and IC4 (74ls367). My board then plugs into these sockets and the '245 and '367 plug into my board. A jumper allows selection of
 CoCo 2 or CoCo 3 mode. I will post this on my webpage soon. -jeric




________________________________
From: Gene Heskett <gene.heskett at verizon.net>
To: ColorComputer at yahoogroups.com
Sent: Friday, January 30, 2009 11:15:18 PM
Subject: Re: [Coco] [Color Computer] Multi-Pak Question

On Friday 30 January 2009, seanrussoct08 wrote:
>Hi all coco-ers!
>
>I have a quick question.  I have a multi-pak 26-3124 that i bought off
>of Ebay a few years ago and haven't used it much.
>
>I had a friend several years ago tell me that he thought you could use
>one of these multi-paks to access more than one device at a time, but
>i didn't think you could.  Could someone settle this for me? and if
>yes, how do you?
>
>2nd, if i buy the hardware from cloud9 to convert this to a coco3
>capable multi-pak, will it never work on my coco2 again?
>
>Thanks,

Sure, no problem.  The fix, fixes an erronious ghosted response from the poor 
address decoding the original did, and which clashed with the gime chip 
register addresses.


-- 
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)
Any program which runs right is obsolete.

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