[Coco] Multipak redesign/replacement / New CoCo...

[Gene Heskett]

On Tuesday 24 February 2015 21:15:34 RETRO Innovations wrote:
> On 2/24/2015 1:35 PM, Gene Heskett wrote:
> > The 80 wire cable with 3 40 pin headers on it that I just checked,
> > appears to have 34  usable connections in it, there are 6 of the pins on
> > the side with the blocked pin tied together.  I wonder if there are true,
> > 80 pin IDC connectors available for that stuff.
>
> According to the above, that's 33 lines (6 pins + key) = 7
>
> According to the link I went to, there are 7 ground lines:
> 2,19,22,24,26,30,40 (all connected to the internal 40 ground lines)
> And, then pin 34 is removed
> Pin 20 is a key
>
> So, while 34 might be available, I think 32 (or 31, if it's an ATA66
> cable and pin 34 is removed) are all you can guarantee as available.
>
> > So the 34 I just measured isn't enough.
>
> If you dropped SND and maybe ditched address line 14 and 15 (it appears
> as though nothing on the expansion bus is accessible below c000, so
> address line 14 and 15 are always high), and maybe removed another line
> (not sure what), you could get there.  But, that's a pretty poor design
> decision just to use a cheap cable.

I'll concur, which is the reason I did a bit of googling for wire & connectors 
we CAN use.

Cheers, Gene Heskett
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