Re: What type op eeprom

[Ken Yap <ken@nhj.nlc.net.au>]

>Hi,
>I'm new to eprom programming, and I've just aqquired a Hi-Lo SEP-81AE
>eprom
>programmer.
>So to get started, what type of EEPROM should I buy?
>The purpose is to boot 3com 503's and 509's, and NE2000's.
>
>The catalog of the dealer I use lists something called: X28C256S-25,
>32Kx8 EEPROM.
>
>Would that fill the ticket?

I assume you meant EPROM and not EEPROM, which is electrically erasable.
You don't *really* need EEPROM although it's nice because then you don't
need a UV eraser if you want to reuse the EPROM. But you do have to have
a hardware setup that can apply the right voltages to pins if you want
to erase an EEPROM.

I think 3c503s only take 8kB images but you may be able to put a larger
EPROM in the socket provided you program the right half or quarter of the
EPROM or replicate the image in the space. 3c509 will accept a range of
sizes. NE2000s are not really one brand but lots of clones. So it depends
on the manufacturer. The original NE2000s took 8kB EPROMs. Taiwanese
clones can probably take 16kB or even 32kB EPROMs. See

	http://www.slug.org.au/etherboot/doc/html/README.html

for a longer discussion. Personally I use 16kB EPROMs (27128), I have
heaps extracted from old motherboards and video cards.

In short the answer to your question is yes. :-)