Date   : Tue, 15 May 2012 02:43:53 +0100
From   : paul2004v@... (Paul Vernon)
Subject: Master won't work after storage

> Date: Tue, 15 May 2012 01:01:01 +0100
> From: bbcmicro@...
> To: bbc-micro@...
> Subject: Re: [BBC-Micro] Master won't work after storage
> 
> On 14/05/12 12:56, J.G.Harston wrote:
> > If it's come out of storage, the classic electrical installation
> > exam answer is to leave it unused for 24 hours to acclimatise
> > so any damp it's picked up in storage dries out.
> 
> I did that, I left it in a warm dry room for over 24hrs, and everything 
> else that was in the same box is fine bbc+, electron, disc drives etc
> 
> > Also, check all ICs are firmly seated into their sockets, you look
> > like you're getting the results of the ROMs not being sufficiently
> > plugged in properly.
> 
> There are only 2 socketed chips on this machine, D7002C (a/d converter) 
> and IC24 which is the OS ROM iirc...
> 
> I've temporary rigged up a battery pack, but it made no difference.
> 
> One thing I've just noticed is that when I get "terminal" or whatever on 
> the screen followed by a flashing cursor pressing BREAK clears the 
> screen to a flashing cursor.
> 
> The power LED is lit and the cassette motor relay clicks.
> 

I'm pretty sure that the last Master that did that to me required a 6522 
VIA to be swapped out. I ended up sticking a turned pin socket in so I could
replace the chip with ease if it ever did it again... IIRC it was the 6522
in IC8 that was responsible in my Master.
If it is the 6522 VIA then any key presses including holding down R on power
up won't do a thing as that chip is amongst other things responsible for
an addressable latch which controls r/w operations to the RTC, keyboard and
sound hardware.
Paul