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From: toddpw@nntp-server.caltech.edu (Todd P. Whitesel)
Newsgroups: comp.sys.apple2
Subject: Re: Video Overlay Card software?
Message-ID: <1991Jan14.214626.4775@nntp-server.caltech.edu>
Date: 14 Jan 91 21:46:26 GMT
References: <14833@smoke.brl.mil>
Organization: California Institute of Technology, Pasadena
Lines: 30

gwyn@smoke.brl.mil (Doug Gwyn) writes (quoting some stuff I wrote):

>>Unfortunately, GS/OS allocates space for handle structures at $e0/6000 (right
>>in the middle of the screen) early on in the boot process
>Oh, ugh.  Is that why the thermometer box's upper left corner changes to
>light-blue background color partway through GS/OS booting?

No, that's a little debug indicator they left in. I believe it indicates that
the system is finished loading and that the startup application is being run.
When I said 'middle of the screen' I meant the middle of the second screen that
provides the extra 200 lines of graphics to the VOC, not the primary screen
everyone is used to.

>Is there some way to automate this fix?

There is. It requires running a little P8 program before starting GS/OS. I'm
debating the best way to implement it (currently I have to run something from
my P8 selector and then run GS/OS). It will be released in a few days with
the initial LHG beta so people can use the VOC modes to display GIFs.

>Sounds like GS/OS should at its very beginning tell the memory-manager tools
>about all the areas with reserved uses, such as display pages.

It does. The secondary SHR page (which is what's in question here) is specific
to the VOC, and GS/OS currently does not check for it. By the time the VOC
inits and such are run, it's too late anyway because the memory has been used
for handles (which can't move once they are allocated).

Todd Whitesel
toddpw @ tybalt.caltech.edu