Date   : Mon, 15 Mar 1993 19:52:10 GMT
From   : "M.J.Ebourne" <M.J.Ebourne@...>
Subject: Re: Minimum configuration?

> Obviosly I need a 6502, and I think I need a 6845 to do the memory refresh 

Definately.

> (they left the RAM in, as its all soldered).

Big deal!

> I can obviously live without the model B stuff, but do I need all of the  
> model A chipset? Can I live without a Video ULA (If I don't want video -  
> though I probably do), a system 6522?(I don't want sound, and probably don't 

> want a keyboard - I'll install a serial ULA, and use my current machine as
a  
> keyboard).

I reckon it would be cheaper to get hold of a complete second hand board.

If you are gonna write your own os, you don't need a system via, but it
would be recommended.

You might get away with a video ula, but I am by no means sure on this.

> I do remember that they don't power up without a keyboard, but figured that 
> that was simply because the break key was on there (or some other simple  
> fix).

I think not. The break key is just a make switch, so unless pressed you can't
tell whether its there or not. I think it is the os getting upset. But then
again, you're gonna write your own by the sounds of the above!

> The problem realy has wto parts to it, as I;m sure that most of the hardware 
> I'll be dependant on will only be required if I run the MOS - how much more 
> culd I get away with if I ditched that too (or patched it?).

Most of it. You definately need the cpu, 6845, (presumably the ttl stuff is
still around, 'cause if its a bare board, I'd definately not bother),
and possibly one or two other bits.

> I've a few ideas for things I could do with it - A second display would be 
> nice. Failing that I could use it for a Teletext server.

Sounds like fun...

> It's pretty unfortunate that both the Video and Serial ULA's are missing as 
> these will be hardest to get hold of. Anyone like to comment on my chances 
> of getting this thing going? (Anyone got a pile of spare parts they're  
> willing to part with?).

The ulas are kinda specialised. You might find an Acorn dealer with a couple
of them lying around - do watford still sell them?

--
Martin Ebourne                             Email: mje@...        
Electronics, Southampton University