> Date: Wed, 17 May 2000 12:56:13 -0400
> From: PORTVAX@trailing-edge.com
> To: PORT-VAX@netbsd.org
> Subject: Vaxstation graphics to SVGA monitor?
> Delivered-To: port-vax@netbsd.org
> 
> Does anyone here have any experience hooking VAXstations (anything
> from VS2000's to 3100's with SPX or GPX graphics to 4000VLC's and 4000/60's)
> to a modern multisync SVGA monitor?  It'd be nice if the monitor accepts
> sync-on-green, but if not I'd be willing to build my own sync
> separator.  And obviously the multisync SVGA monitor will have to handle
> the scan rates from the vaxstation(s) - but unfortunately I'm having a hard
> time getting scan rate details on many modern commercial SVGA monitors.
> The specs usually list the supported resolutions, but not the actual
> scan rates.

Frequently you can find the range of supported scan rates by digging
deeper on the monitor manufacturer's web page.  IBM is really good
about this for their 16" LCD monitors.

You can learn a lot by going to a Linux system and reading XF86Config.
The lines labeled "Modeline" spell out the display timing that is used
by various monitor and graphics generator configurations.  e.g.

# 1024x768 @ 76 Hz, 62.5 kHz hsync
Modeline "1024x768"    85    1024 1032 1152 1360   768  784  787  823

This is parsed as:  video BitClock 85MHz
Horizontal 1024 pixels displayed, sync pulse 1032 to 1152, 1360 total
(units are periods of BitClock) Horizontal rate is 85MHz/1360 = 62.5KHz
Vertical 768 lines displayed, sync pulse 784 to 787, 823 total
(units are periods of Horiz sweep) Vertical rate is 62.5KHz/823 = 75.94 Hz

There is also a table of monitor characteristics to be found in
/usr/X11R6/share/Xconfigurator/MonitorsDB, at least on some Linux systems.

    carl