|Re: HHP EPROM|
Message #12 Posted by Ellis Easley on 18 May 2003, 6:44 p.m.,
in response to message #10 by Kim
On the EPROM (I assume it needs a 28 pin DIP - Dual Inline Plug - part) - the Fry's near me has a small selection of electronic parts in individual bags hanging from pegboards, including some EPROMs. Not the "NTE" replacement line, which Fry's also carries, but just Fry's own bagged parts. That might be as good a place as any to get one part. Or you could try DigiKey:
This page has Fairchild DIP EPROMs for $3.62:
Note that "OTP" means "one time programmable", an erased EPROM in a plastic package without a quartz window that can't be erased again. This page has Atmel DIPs for $1.94, but they are OTP:
Another place is Mouser Electronics:
This page has ST DIPs for $3.30:
This page has Fairchild DIPs for $6.44:
This page has Atmel OTP DIPs for $3.30:
Both catalogs have 32 pin PLCC OTP's. My HHP brochure doesn't specify, so I assume it uses 28 pin DIP EPROMs.
If it does have a PLCC socket - they do (or used to) make PLCC-type EPROMs in ceramic packages with quartz windows, but they never fit in the sockets very well - the "P" in PLCC means plastic and the real similar part in ceramic is the "leadless chip carrier", so the compromise ceramic PLCC is really a leadless chip carrier with "J" leads brazed on, it just doesn't take the socket's spring force as well as a real PLCC.
The Mouser website is better - you can browse lists of part numbers for categories like "EPROMs", then after selecting a part, you go to a PDF of the catalog page with prices and more specs.
You can find EPROMs in various old electronic equipment like VGA boards, motherboards, disk drives - if it has a paper label, peel it off and see if it has a quartz window and the right part number. Then you'd need to erase it - I've heard you can erase EPROMs by leaving them in the full sun for some time (days?) Whether with sunlight or a proper eraser, to erase it completely you have to remove every bit of adhesive left by the label, 91% rubbing alcohol is good for this.
BTW, DigiKey carries the Needham's programmers, this pdf is the page from their online catalog: