I didn't see this message earlier. Tim and I have been discussing support for fixed-frequency displays off-line, trying to whittle down the on-chip logic to the absolute minimum hook to interface with an external SPI device that can set an arbitrary video mode. Once the ASIC has the hook to read in an externally set arbitrary mode, the external tool could be implemented in a variety of ways to suit different users' preferences. It could be just a bank of DIP switches to set the dot counts in raw binary form, or it could be something with an embedded microcontroller and an RS-232 interface that lets you type in the timing specs from a terminal and re-flash the EEPROM when you're satisfied it works. Or something else. If you want to leave it permanently plugged into the OGC1 board and install it in the target computer, you probably want the DIPswitch board. As far as determining the mode settings for a monitor that doesn't do EDID, you usually have to find its data sheet to get the timing specs. Next, you look up Eric Raymond's "Video Timings HOWTO" in linuxdoc, and perform the calculations to get the video mode numbers. It worked for me on the first try.
-------------- Original message ---------------------- From: "Diego Sáenz" <[EMAIL PROTECTED]> > El Fri, 25 Aug 2006 16:53:34 +0800 > "Rogelio Serrano" <[EMAIL PROTECTED]> escribio: > > > On 7/31/06, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: > > > I'm not worried about getting the video controller to run at a given > > > mode > at > > > boot time. My concern is how to figure out what that mode should be. > > > How > do I > > > figure out what mode my old 20" Sun fixed frequency, sync on green, montor > > > connected via a hd15->13W3 converter should run at boot time. Monitors > > > that > > > support DDC aren't a big problem, but ones that don't are very hard. > Perhaps in > > > the end, a user configurable default video mode should be available in > > > situations where the card simply cannot tell what to do. > > > > > > --Patrick M > > > > I think whats needed is a ddc capable adapter box separate from the > > card is better. that box can have headers or whatever switching > > arrangement is necessary to tell the card what the preferred mode is. > > that way whatever fixed mode hardware is "standardised". > > This can be a great idea and can be sold independently. > It will be more expensive for the box and the extra shifters but may be it > compensates with extra solds. > > Diego. > _______________________________________________ > Open-graphics mailing list > [email protected] > http://lists.duskglow.com/mailman/listinfo/open-graphics > List service provided by Duskglow Consulting, LLC (www.duskglow.com) _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
