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cubieplayer / Cubian

Debian for Cubieboard
http://cubian.org
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some monitors flicker with cubian on cubietruck #397

Closed fspegni closed 9 years ago

fspegni commented 9 years ago

Hallo,

I've just installed your Nano image and installed the X support following:

http://cubian.org/2013/09/29/install-lxde-with-opengles-accelerated-on-cubian/

I noticed that while I attach the board at a small toshiba (model 19AV734G( monitor, everything works ok. when I connect it to a bigger samsung tv (model LE46C630K1WXZG) it starts flickering as soon as the cubian driver is shown at boot.

the flickering is not constant: it happens every few seconds (maybe every 30"), and it lasts maybe one second. during the flickering I can still see the background and all the application, but it's very disturbing.

is there any way I can help you to debug this? should I run some command or send you some file as additional information?

thanks for this project, very simple and well documented

michalliu commented 9 years ago

Maybe the kernel failed to detect your screen resolution, You'd better change the kernel command line, follow this issue to resolve it.Please let me know your result, thanks. https://github.com/cubieplayer/Cubian/issues/386

fspegni commented 9 years ago

I followed the instructions, but the outcome didn't change.

One thing I've noticed is that if I:

  1. plug TV SVGA cable to cubietruck
  2. turnon cubietruck
  3. power on TV

it doesn't flicker. If I switch steps 1 and 2 it works as well. If I move step 3 before step 2, it flickers. In order to stop flickering I can run the following script:

# xrandr --newmode "1024x768_60.00" 63.50 1024 1072 1176 1328 768 771 775 798 -hsync +vsync
# xrandr --addmode default 1024x768_60.00
# xrandr --output default --mode 1024x768_60.00

it seems to me it may not be a problem of "right" kernel parameters. does it ring any bell to you?