[Coco] 4 Port MPI PCB artwork (so far)

RETRO Innovations go4retro at go4retro.com
Wed Mar 4 23:38:37 EST 2015


On 3/4/2015 3:50 PM, camillus blockx wrote:
> That's ok Jim
>
> Please keep me posted.
> Do you have knowledge of the SDMC ( floppydrive emulator), and the PCLD's
> that is used in it, I was wondering of merging the two together in one?
You can, but if you assume that the project uses *most* of the CPLD 
space it has, you have to add them together to find a part suitable for 
merging.

SO, this project uses a 9572, which has 72 macrocells and it uses 51 IO 
lines.  The CocoSDC needs a 9572 as well and uses up to 34 IO lines..  
Mine is ~50% full, I assume Darren's is 100% or close. Thus, to merge 
the designs, you need 72+36 macrocells, and you need 51+34 IO, so you're 
looking at a 95144, but more than a TQ100 part, so you have to go with 
144 pin part.  CPLDs gets somewhat expensive as the macrocells and pin 
count go up.  The cheapest I see that part is $7.50, and Darren's CPLD 
costs $2.26 and mine costs $2.66, so it is actually cheaper (and easier) 
to leave them separate.
>
>
> Can you btw tell me where you found the connectors?
In expectation of this project, and to get a good deal on them for other 
people and such, I made a bulk order from a firm I typically buy my 
Commodroe 22/44 connectors from.  It's a business purchase, with wire 
transfers and such, not a retail place.

But, I have 1000 of them coming, so I'll put a bunch in the store, and 
try to price them economically so everyone can have a batch if they want.





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