Geoffrey Hausheer writes: > > > > > Another update on My Twinhead Powerslim 600 with the Cyber9525DVD: > > > > I changed the hsync hardcoded adjustment to 0 (it was initally 23) > > > > I left the vsync at -2. > > > > > > This will break it for others. We still don't know exactly how to > > > calculate these values exactly. > > > > I've done some playing around with my laptop based on a Trident > > Cyber9525DVD, and I'm beginning to believe that the CRTC values can't be > > correct. In particular, the CRTC values change from what X sets when I > > press Fn-F5 to switch displays, and when I plug these values into the LCD[] > > array, the overlay becomes centered properly (without modifying the > > h/vsync). > > Thanks for figuring this out! Now that I know what's causing the Xvideo offset > to re-occur, I can switch to console and back to restore it to being 'centered'. > Sure it's not a perfect fix, but I expect y'all will figure that out before the > next major release :) If there's anything I can do to help, please let me know. >
First of all: The CRTC values we set _are_ correct. They work for a wide range of displays. The values I have commented out came from my test system but they caused problems on several boxes. They may not be the same your system sets up - that doesn't matter as long as they work. I still have no clear idea how the offset registers need to be caluculated. The documentation says to use the number pixel clocks (lines in case of the vertical offset) between the rising edge of the h/vsync and the begin of the video frame. If we do that we need to add an offset which has been obtained empirically. For some reason this offset differs from chipset to chipset (or even from system to system). If the CRTC values set by the BIOS cause the video to be displayed correctly it would be interesting to know which values exactly make the difference. Egbert. _______________________________________________ Xpert mailing list [EMAIL PROTECTED] http://XFree86.Org/mailman/listinfo/xpert
