[Openchrome-users] turn off the backlight on LCD panel

[Xavier Bachelot]

Brad Reeves wrote:
> I have a system built on the VIA NR10000EG with CX700 graphics.  I have 
> installed the latest openchrome from svn about a month ago.   I am 
> running Xubuntu 8.04LT and cannot figure out how to turn off the backlight.
> 
> i have tried the screensaver, however the screen blanks but the 
> backlight is still on.  Also tried "xset dpms force off" with similar 
> results - blank screen, backlight stilll on.
> 
> I have attached my xorg.conf.
> 
The xorg conf is not the most important here, please provide the xorg 
log (compressed). And also, it would be much better if you update to 
latest trunk first.

 From your xorg conf :

Section "Device"
         Identifier      "Configured Video Device"
         Driver          "openchrome"
#  required for LCD panel
         Option   "ActiveDevice" "LCD"
         Option   "VBEModes" "true"
         Option   "PanelSize" "1024x768"
#fixes a redraw problem in xubuntu
         Option  "EnableAGPDMA" "false"
EndSection

Section "Monitor"
         Identifier      "Configured Monitor"
# to disable screen blanking
         Option  "DPMS"
EndSection


How is your panel connected to the board ? VGA port ? DVI/HDMI port ? 
Internal LVDS port ?
Why do you need to use VBEModes ?
Why do you need to force the PanelSize ?
If your using the DVI port, which might explain the VBEModes and 
PanelSize option, there's native support for the CX700 TMDS encoder in 
trunk, so these hacks are probably not needed.

Why do you need to disable AGPDMA ? This is possibly fixed in SVN too.

Also, Option "DPMS" is _not_ disabling screen blanking, you need to use 
Option "DPMS" "0".

Regards,
Xavier