Date   : Thu, 25 Oct 2007 18:34:05 +0100
From   : julesrichardsonuk@... (Jules Richardson)
Subject: System VDU board (p/n 200,002) manual?

Does anyone have a manual for the System VDU board (200,002)? I've got two 
boards here - issues 3 and 4 - but my manual's an issue 1, and the schematics 
don't quite match up (my schematic's branded 200,002/C)

On both boards, there's a PCB link for shorting pin 13 of IC12 to ground (pin 
13's otherwise left floating and hoped to register as a high it seems - 
there's a PCB marking for a pull-up resistor, but it's not fitted to either of 
my boards).

On my issue 4 board, there's a switch on the card edge wired to the PCB link; 
I'm not sure if that's someone's later mod or an official Acorn one (the issue 
4 board also has the RGB DIN socket present - the issue 3 board just has 
composite connector only).

The link appears to enable composite output - or at least composite doesn't 
seem to work without it :-) It'd still be handy to know for sure what it's 
doing, though. (On the issue 1 boards, pin 13 of IC12 is connected to an 
output of a flip-flop; shorting it to ground wouldn't make much sense)

Ta

Jules