Date   : Fri, 25 Jul 2008 09:16:49 +0100
From   : Charlie.Robson@... (Charlie.Robson@...)
Subject: EEPROM writing in SW rom bank?

jgh@... (Jonathan Graham Harston) wrote on 25/07/2008 
02:00:29:

> 
> IC77p8 is the ususal write strobe collection point. I though I'd
> documented it@...<http://mdfs.net/Info/Comp/BBC/SROMs>, but I've
> only done it for 32K devices.
> 
> Somebody mentioned flash. I seem to remember that EEPROMs need to
> be written in a cycle, which I think is similar to flash, using
> code something like:
> 
> LDA (src),Y
> .lp
> STA (dst),Y  :\ Write byte
> CMP (dst),Y
> BNE lp       :\ Keep writing until read byte matches
> STA (dst),Y
> STA (dst),Y  :\ Twice more for luck
> 

I'm already following the write/test cycle but there's a further
twist here - I might just have one last attempt at writing until
it 'takes'.. It's possible that the waveforms might coalesce if
pushed hard enough ;)

Ah well I live in hope!

> STA (dst),Y  :\ Twice more for luck

LOL!


Thanks for the input everyone.




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