Subject: Re: cg14 "modelines"?
To: NetBSD port-sparc mailing list <port-sparc@netbsd.org>
From: Julian Coleman <jdc@coris.org.uk>
List: port-sparc
Date: 01/04/2007 10:16:45
> r1024x768x60   1024  768 60  64125000 128  6 160 29 16 2
> r1024x768x66   1024  768 66  70400000 124  5 160 39  4 1
> r1024x768x70   1024  768 70  74250000 136  6 136 32 16 2
 
> The first three are pretty bonehead-simple. :)  The fourth is less
> clear; I speculate that it's some kind of pixel clock frequency -
> certainly the ratio between it and the product of the first three is
> both notably close to constant and frustratingly non-constant.  The
> rest of them look pretty mysterious to me.

Looking at information on building mode lines for XFree [*], could the other
entries be related to the horizontal and vertical pulse positions?

I would also imagine that the 4th entry is the pixel clock.  I don't know if
there are a fixed set of allowed values or anything in a range is allowed.

If I'm correct, you could probably make a 1600x1200 entry by altering just
the vertical component - maybe the last 3 entries (I'm guessing here).

It would also be neat to be able to set resolutions from userland.  I wonder
if the source for the SunOS/Solaris tool to do this is viewable anywhere.

J

[*] See (for example) sections 11 and 12 of:

  http://tldp.org/HOWTO/XFree86-Video-Timings-HOWTO/

-- 
  My other computer also runs NetBSD    /        Sailing at Newbiggin
        http://www.netbsd.org/        /   http://www.newbigginsailingclub.org/