Date   : Fri, 04 Nov 2005 21:10:02 +0000
From   : "Nick B." <nick@...>
Subject: Re: Possible EPROM???

Andrew Benham wrote:

> Phil Blundell wrote:
>
>> On Sun, 2005-10-30 at 00:24 +0100, Jonathan Graham Harston wrote:
>>
>>> Is there such a thing as a 28-pin 128K EPROM with A16 on pin 22? A
>>> 271024 maybe? For years I've been meaning to replace the system
>>> ROM with one with my own choice of contents:
>>
>>
>>
>> Not that I can think of (27C1024 is a 16-bit wide device in a 40 pin
>> package), but it'd probably be easy enough to make a little socket
>> adapter to take a 27C010 or equivalent (128Kx8 in 32-pin DIP).
>
>
> Even easier when the instructions are out there:
>
> http://www.adsb.co.uk/bbc/adaptor.html
>
I did build one of these a while ago - a useful source of 32 pin 128Kx8 
EEPROMS (as opposed to EPROMS) is the BIOS flash memory on old Pentium-1 
motherboards which can be picked up for a pittance at computer fairs, or 
as scrap from upgraders. You'll need an EPROM programmer that supports 
them though, then you can re-flash and erase your own Master ROM to your 
heart's content...

Rgds,
-- 
Nick B.