Date   : Sat, 13 Nov 2010 00:34:23 -0000
From   : jumbos.bazzar@... (Mark Haysman)
Subject: ROMs

----- Original Message ----- 
From: "Theo Markettos" <list-a_cloud9.bbc-micro@...>

> A 28F010 will cost you a fiver:
> http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=0540949
> (a 28F512 is the same price)
> or a 28F020 (256KByte - 16 ROM slots!) for 6.42:
> http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=0540977

Most (all?) 28Fxxx devices are 12v for programming, so best to use a 29F010 
or 29F040 for 5v operation. Also, keep in mind the sector sizes, the 
AM29F010 for instance:

http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=6261425

is a 16k sector size, which is just right, as Beeb ROMs are 16k, but a 
29F040 will have 64k sectors, so when you want to reprogram one ROM, you 
have to erase 4, and put the other 3 back manually.

There are probably other devices that are large, but have small sector 
sizes.

Mark.