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From: rps@dtseng.UUCP (Robert P. Scott)
Newsgroups: comp.sys.ibm.pc,comp.graphics
Subject: VGA -> Combined sync on green type monitor
Keywords: VGA Composite Sync RGB
Message-ID: <7182@dtseng.UUCP>
Date: 16 Nov 89 05:33:53 GMT
Organization: DTS Engineering, Hudson, NH
Lines: 26

I'd like to drive an RGB monitor which expects sync signals on
the green video line with a standard VGA card.  Has anyone out
there tried to do this? 

I have no VGA specs, but I've heard that the H and V sync signals
from the card are TTL levels.  To further complicate things
I've heard that one or both of the signals are inverted to help
multisync monitors?  Is this the case?

Assuming the monitor is AC coupled I figured I could just use a
few resistors to combine the syncs and green.  But can I prevent
(in software, hardware would work but I would prefer a passive
cable...) the sync sense from being mucked with?

Please e-mail responses to ...!decvax!dtseng!rps as I rarely have
time to read news.  I'll summarize and post my results.

Thanks,

Robert

-- 
D T S  Engineering     |  Robert P. Scott
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