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Forum Topic - Low-resolution graphics modes support: (5 Items)
   
Low-resolution graphics modes support  
Just tried to setup 320x200@70Hz video mode using devg-tnt on GF2MX400, and TFT monitor says: "Frequency out of range". 
Not tried it yet on devg-radeon, but I think result will be the same...

Maybe somewhere exist list of video drivers, which video drivers support low-resolution video modes (e.g. doublescan 
modes) and which are not ?

Also it would be nice if each video driver which has lack of low-resolution   video modes support will report an error 
when such video mode parameters are given to the video driver instead of setting bogus CRTC/TMDS values.
RE: Low-resolution graphics modes support  
Sounds to me like the TFT monitor can't handle the resolution and
frequency combination. Try an old fashioned CRT.

Max 

-----Original Message-----
From: Mike Gorchak [mailto:community-noreply@qnx.com] 
Sent: Tuesday, March 17, 2009 8:46 AM
To: advanced-graphics
Subject: Low-resolution graphics modes support

Just tried to setup 320x200@70Hz video mode using devg-tnt on GF2MX400,
and TFT monitor says: "Frequency out of range". Not tried it yet on
devg-radeon, but I think result will be the same...

Maybe somewhere exist list of video drivers, which video drivers support
low-resolution video modes (e.g. doublescan modes) and which are not ?

Also it would be nice if each video driver which has lack of
low-resolution   video modes support will report an error when such
video mode parameters are given to the video driver instead of setting
bogus CRTC/TMDS values.


_______________________________________________
Advanced Graphics
http://community.qnx.com/sf/go/post24537
Re: RE: Low-resolution graphics modes support  
No, there is no difference between CRT and TFT monitors in this case, because TFT emulates CRT. But old VGA modes like 
320x200, 320x240, 360x480 requires doublescan support in the video hardware, and 320x200, for example, became 640x400 
for CRT or TFT monitor.

Video drivers without doublescan modes support will output real 320x200 to monitor but with very low pixelclock, which 
monitor can't handle.
Re: RE: Low-resolution graphics modes support  
Any of our drivers that use direct/generic modeswitching do not support doublescan modes.     The only drivers that will
 allow you to display less than 640x480 on a CRT/TFT monitor would be ones that use the video BIOS to detect/set the 
graphics mode.
Re: RE: Low-resolution graphics modes support  
Thank you, Michael. If there are no support for low-resolution modes, it would be nice if video driver will return some 
error code instead of trying to set wrong video mode parameters.