[Coco] 2764 EPROM

[Bruce W. Calkins]

>> What Rodger is referring to is the later packs that had a
>> small blob of black plastic in the middle of the small board.
>>  Not a whole chip in sight.
>>
>> Bruce W.
>>
>>
> From: "Paul Fitch" <pfitchjr at bellsouth.net>
> Well, it's the early pacs I'd think would be up for recycling.  Some of
> those first rom pacs were were pretty lame.
>
> Still, what he really needs it what he originally asked for.  A stack of
> blank PCBs suitable for plugging into the expansion port of the Coco. 
> Radio
> shack used to make something like that, but I doubt there are any left.
>
>
The very early ROM packs used 4K ROMs, Sometimes two of them.  Later 
versions used a single 8k ROM.  I combined two of them into one by 
piggybacking the chips with a switch to select between them.  By the time 
things evolved to the 16K ROMs they were apparently SMDs covered with a blob 
of black plastic looking stuff.  There may be a few other variations, 
especially among third party sources.  However I have not seen anything that 
had all the address lines needed for a 16K EPROM that could take a socket, 
or a conventional DIP chip.



There were a few boards from Radio Shack and others that plugged into the 
CoCo port.  Most only had solder tabs on the port end.  I built an EPROM 
Burner on one.



There are several on this list that would be interested in prototyping 
boards, if it did not break our banks.  I am thinking along the line of ones 
with a socket for a 8K to 32K EPROM.  Perhaps with bank select switches and 
space to work up other projects.



Bruce W.