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Date Posted: 06:42:31 10/04/01 Thu
Author: Potter
Subject: Re: AGC problem, changing code...
In reply to: viZion 's message, "AGC problem, changing code..." on 09:35:17 10/03/01 Wed

You'll need to closely check your local scrambling with a cro to identify a reliable black level reference then insert the control port commands into the code within makehline, remembering to compensate for the cycles used by reducing the appropriate 'wait' loops. The chosen video line is easily identified by setting a flag in the main loop (assuming your box is locked onto the signal).
I'm on a 50 Hz PAL Tocom system with random video inversion and line 16 was convenient to take the reference between the end of the colour burst and the next sync pulse which is about 50 uSecs. There's no reason why the burst could not be included as its average is the black level anyway (normally at least)

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