Question about ZD* pin on Denise

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#12914

From: Enno Davids
Date: Mon, 29 May 1989 08:38

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Just a quick question about the ZD* (Background Indicator), pin of Denise.

A developer friend (with no net access) has built a Genlock and is using
this pin as a keying signal. One particular video package seems to cause
this pin (pin33 in a PAL A1000) to produce a composite sync signal with
warped timing. (Stretched Hsync's with Vsync delayed by '1 video block',
about 26 lines I am told).

From a cursory examination of the hardware manual it seems that the anonymous
developer of said video package might be hitting the the GAUD bit in BPLCON0.

So, the questions are, what functions can pin33 of Denise perform, how does
one control these functions, is this an 'undocumented limitation' (read:
bug) of the package in question, any other relevant information, etc.
Most simply, is this something he can expect to workaround in hardware or
should he rely on a software update that displays better behaviour.

Please send replies to me (or post them) and I will pass them on.


Enno.


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Path: arc1-ca.pugleaf.net!utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!uunet!munnari!olympic!enno
From: enno@olympic.oz (Enno Davids)
Newsgroups: comp.sys.amiga.tech,aus.computers.amiga
Subject: Question about ZD* pin on Denise
Keywords: Denise, ZD* (Background Indicator), Genlock
Message-ID: <944@olympic.oz>
Date: 29 May 89 08:38:36 GMT
Organization: Olympic Amusements, Melbourne, Australia.
Lines: 34