[Coco] PART NEEDED

Roger Merchberger zmerch-coco at 30below.com
Mon Aug 13 11:42:19 EDT 2007


Rumor has it that Darren A. may have mentioned these words:
>-
>The equivalent 8K UV erasable EPROM for the 24-pin ROMs used in early 
>CoCos is the MCM68766. You can occasionally find these for sale on ebay. 
>Unfortunately, the affordable Willem programmers do not support this 
>EPROM. I have successfully used an Intronics Pocket Programmer 2 to burn these.

Another part number that can work is the 68764 - they're both pin & voltage 
compatible, but IIRC the '64 came in faster speeds and might've had a "low 
power mode" or somesuch - I'd have to check datasheets to be sure.... but 
for the CoCo's sake, they're equivalent.  That said, I have a metric 
buttload of them, but they're in special carriers as these chips were also 
used in the Panasonic HHC which were very popular with insurance sales markets.

The pins can be straightened back out for use in a CoCo, if one is careful 
during the straightening process. I also have a programmer that can program 
these - my Xeltek SuperPro/L works just fine with these chips, and I've 
programmed several.

=-=-=-=

My only question (and this is the conspiracy theorist in me coming out - 
it's rare, but it does happen) is why does the OP need "several?" Last time 
I had a request like that, it was for a guy (also named Mike - I haven't 
deleted non-spam email in 10 years) who was looking for the Panasonic HHC 
Basic... which at the time I didn't have. (Chips I had, code I didn't.) He 
eventually found it, made some, and sold them on ePay for $50+ each. He 
then tried to buy more chips from me.

I'm happy to help if this isn't a similar situation.

Laterz,
Roger "Merch" Merchberger

--
Roger "Merch" Merchberger   | "Profile, don't speculate."
SysAdmin, Iceberg Computers |     Daniel J. Bernstein
zmerch at 30below.com          |




More information about the Coco mailing list