#ifdef README

Date: Fri, 18 Oct 2002 16:20:59 -0400
Subject: Re: contribution for your O2 stereo web page
From: Simon Lok  [[(lok at cs dot columbia dot edu)]]
To: Stuart Levy <slevy@ncsa.uiuc.edu>


On Friday, October 18, 2002, at 04:11 PM, Stuart Levy wrote:

> On Fri, Oct 18, 2002 at 03:58:22PM -0400, Simon Lok wrote:
>> well... not stereo, but still relevant.  below is the vfs source code
>> needed to build a vfo file for a SGI 1600SW flat panel running in
>> analog mode at native 1600x1024 resolution, 60 hertz, such that the
>> analog video output > lines up pixel for pixel with the panel.
>> the panel's settings should be > set to the factory default
>> (easy with the factory reset switch).
>
> Coolio.  But... is this for an O2?  I thought that SGI supplied
> a 1600x1024_60p flat-panel video format already.
> Have you tried that one too?  Does this format behave differently,
> or are you just offering this .vfs so there'll be source available?
>
>    Stuart

Indeed it is for an O2.  Most people who own O2's are willing to
pay the $850 for the flat panel adapter kit (which includes a color
calibration thingie and software and cables and and and and and...)
when all you really want is the P/N: 030-1170-001board that is
probably worth $5.00 on a good day.

Being the cheap bastard that I am, I have an O2 and 1600SW with
a multilink adapter on it.  At the time when I bought the 1600SW
two years ago, it was the same cost if it came with a PCI graphics
card or the multilink.  Since graphics cards like get better all the 
time
and i was going to use this thing with an O2 anyway I got the multilink
and ran in analog.  I figured that if I hacked hard enough at some
point some day it would look as good as digital.  About a year ago
I got the pixel for pixel matchup but not the horizontal adjustment
and whatnot.

So yesterday I just put a 76GB SCA-2 disk into the internal bay
of the O2... and of course, I needed to reinstall the operating system.
And of course I forgot the copy of the old vfo file that I made.  And of
course, the old 18 GB disk i had in there was already reformatted
and being used elsewhere.

Anyway, enough of my troubles.  The 1600x1024_60p.vfo only
works if you have the flat panel adapter AFAIK, and the timings are
set appropriately for digital out (no front porch!).  This 1600x1024
works with the analog output and sets the timings appropriate for
analog out.

As an aside, since it is possible to use both the O2 flat panel adapter
and the analog out at the same time (at least according to the 
installation
manual for the flat panel adapter), this vfs that I've supplied should 
allow
the adventurous user to actually hookup TWO 1600SW displays to
the same O2.

Thanks for your site, it was a tremendous help. Only thing that I would
like to say that might be better is an example source that doesn't use
the IRIX DO.  Being the cheap bastard that I am, I use the freeware
gcc compiler and your makefile make's assumptions about having
an IDO license.

Thanks again!

--SL

#endif /* end README */

General
{
     FieldsPerFrame = 1;
     FramesPerSecond = 60;
     TotalLinesPerFrame = 1056;
     TotalPixelsPerLine = 1702;
     ActiveLinesPerFrame = 1024;
     ActivePixelsPerLine = 1600;
     FormatName = "1600x1024_60";
}

Active Line {
     HorizontalFrontPorch = 12 pixels;
     HorizontalSync = 50 pixels;
     HorizontalBackPorch = 40 pixels;
}

Field
{
     Vertical Sync =
     {
         {
             Length = 1.0H;
             Low = 0.0 usec;
         }
         repeat 2
         {
             Length = 1.0H;
         }
     }

     Initial Low;
     Vertical Back Porch =
     {
         {
             Length = 1.0H;
             High = HorizontalSync;
         }
         repeat 25
         {
             Length = 1.0H;
             Low = 0.0 usec;
             High = HorizontalSync;
         }
     }

     Initial High;

     Active =
     {
         repeat 1024
         {
             Length = 1.0H;
             Low = 0.0 usec;
             High = HorizontalSync;
         }
     }

     Vertical Front Porch =
     {
         repeat 3
         {
             Length = 1.0H;
             Low = 0.0 usec;
             High = HorizontalSync;
         }
     }
}

#if 0
     postprocess
     {
         dump edge;
     }
#endif