Date   : Tue, 01 Oct 2013 19:47:17 +0100
From   : list-a_cloud9.bbc-micro@... (Theo Markettos)
Subject: Doodah identification

In article <fc15a7dcd5725e50ad5a08f0786e4449@...> JGH wrote:
> It has a 74'123 dual flip flop and a 74'00 quad nand gate. There's no
> analogue or sound stuff on it. It's a bit logic and one or two bits
> of state. It looks like it decodes the state of something and remembers
> it for something else.

My guess would be a VIDC enhancer or similar.  Takes in clock frequency,
does optional divide based on link/external switch.  I think the A3xx/A4xx
series had a genlock header with a couple of IOC GPIOs that this might plug
onto.

But I thought they all had their own crystal like this one does:
http://www.retro-kit.co.uk/VIDC-Enhancer/

Theo

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