Path: utzoo!mnetor!uunet!husc6!bbn!rochester!ritcv!cci632!ccicpg!leo!harald
From: harald@leo.UUCP ( Harald Milne)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Fixing flicker, & future frame rate issues
Message-ID: <2987@leo.UUCP>
Date: 21 Apr 88 09:32:41 GMT
References: <1367@hubcap.UUCP> <3626@cbmvax.UUCP> <8712@agate.BERKELEY.EDU> <8928@agate.BERKELEY.EDU>
Organization: CCI CPD (Advanced Development), Irvine CA
Lines: 47
Summary: Hopefully the fix and solution

In article <8928@agate.BERKELEY.EDU>, doug@eris (Doug Merritt) writes:
> But to return to the *original* point: simply that flickerFixer would
> work better if it *only* merged the odd and even scan fields of a
> single frame.


I'm going to base the solution on the following presumptions:

1) When the Amiga powers up, to the day it dies, the stream of
   video information is NEVER interrupted. There is no flipping of
   fields for ANY reason.

2) As Bryan pointed out and as I suspected, FF only stores 2 fields
   of video information. (Odd and Even)

3) Somehow, if it is possible to detect (Hedley I need help on this)
   the start of a video frame, be it derived or otherwise, point to
   point wiring of the motherboard, glue logic, I don't care. We need
   to know the start of a video frame to do this correctly. (Although
   I have one other method to do it otherwise)

4) Buffering 2 video frames will solve ALL problems, no software
   intervention  needed. A hardware solution.

If I am wrong on any of these points, please let me know.
It is very important that these presumptions are correct!!!!!

The solution: (This would be a modification to the existing FF)

1) First, you have to double the storage to 2 full video frames.
   That's easy. Piggy back an extra set of rams, leave the chip selects
   free. Next, divide by 2 the select via a flip flop, feed the rams.
   Viola! Dual frame storage. 

2) Take the derived frame start signal, use it to properly select the rams
   to video frames.


	This is the best and simple solution. If my presumtions are correct,
I will implement this and post the modififaction. I can't stand flaws.

	If I am correct, this is a simple and easy fix.

-- 
Work: Computer Consoles Inc. (CCI), Advanced Development Group (ADG)
      Irvine, CA (RISCy business!) 
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