Screen going blank

[Jason Kridner]

Gerald,

I understand you are having an issue with the screen going blank and are looking for a way to configure the kernel to keep the display.  I believe you can try adding this line to uEnv.txt:

optargs="consoleblank=0"

I'm not sure about the quotes and I haven't tried this.  I'll hook up a board again here after tearing everything down for Indiana Linuxfest and give it a shot.

Regards,
Jason

[Jason Kridner]

On Monday, March 28, 2011 4:21:08 PM UTC-4, Jason Kridner wrote:

Gerald,

I understand you are having an issue with the screen going blank and are looking for a way to configure the kernel to keep the display.  I believe you can try adding this line to uEnv.txt:

optargs="consoleblank=0"

My uEnv.txt looks like:
dvimode=hd720
console="ttyS2,115200n8 console=tty0"
optargs="consoleblank=0"

I've let it sit for a while and the screen hasn't gone blank on me, but I can't confirm it won't yet.  What I can confirm is that the quotes above seem to be working.  The resulting kernel command line I get is:

root@beagleboard:~# cat /proc/cmdline
console=ttyS2,115200n8 console=tty0 consoleblank=0 mpurate=auto buddy=none camera=lbcm3m1 vram=12M omapfb.mode=dvi:hd720 omapdss.def_disp=dvi root=/dev/mmcblk0p2 rw rootfstype=ext3 rootwait

Having the "console=tty0" helps quite a bit by showing the boot activity.  Clearly you want the "ttyS2,115200n8" as the new u-boot will now default to "ttyO2,115200n8" and the 2.6.32 kernel won't spit anything out there.  I think shipping with a uEnv.txt that sets things to hd720 probably makes sense as connecting to an HDTV is probably one of the easiest options for a display.  I don't have an opinion on the consoleblank. 
 

[Gerald Coley]

I will have the guys give it a try!

 

Thanks!

 

Gerald

[srilatha...@gmail.com]

Hi all,

I worked with angstrom demo image and could see an output on tv. While
the kernel boots up i saw an angstrom logo with boot status, and once
the kernel is loaded, i see few folders on tv output..my kernel
bootargs are as follows:

setenv defaultdisplay tv
setenv dvimode 'hd720 omapfb.mode=tv:ntsc mem=99M@0x80000000
mem=128M@0x88000000'
run loaduimage
run mmcboot

Now, I am loading the angstrom demo image with same boot args, but
the tv output is not working. After the initial vertical lines vanish,
tv goes blank(as if board is not connected to tv) after few seconds of
blank display. If anyone had solved this kind of behavior with
Angstrom beagle board demo image, please help me out.

Thanks,
Srilatha.

On Mar 29, 6:48 am, Gerald Coley <ger...@beagleboard.org> wrote:
> I will have the guys give it a try!
>
> Thanks!
>
> Gerald
>

[Siji Sunny]

On Tue, Mar 29, 2011 at 3:08 AM, Jason Kridner <jkri...@beagleboard.org> wrote:
> On Monday, March 28, 2011 4:21:08 PM UTC-4, Jason Kridner wrote:
>>
>> Gerald,
>>
>> I understand you are having an issue with the screen going blank and are
>> looking for a way to configure the kernel to keep the display.  I believe
>> you can try adding this line to uEnv.txt:
>>
>> optargs="consoleblank=0"
>
> My uEnv.txt looks like:
> dvimode=hd720
> console="ttyS2,115200n8 console=tty0"
> optargs="consoleblank=0"
>
> I've let it sit for a while and the screen hasn't gone blank on me, but I
> can't confirm it won't yet.  What I can confirm is that the quotes above
> seem to be working.  The resulting kernel command line I get is:
>
> root@beagleboard:~# cat /proc/cmdline
> console=ttyS2,115200n8 console=tty0 consoleblank=0 mpurate=auto buddy=none
> camera=lbcm3m1 vram=12M omapfb.mode=dvi:hd720 omapdss.def_disp=dvi
> root=/dev/mmcblk0p2 rw rootfstype=ext3 rootwait
>
> Having the "console=tty0" helps quite a bit by showing the boot activity.
> Clearly you want the "ttyS2,115200n8" as the new u-boot will now default to
> "ttyO2,115200n8" and the 2.6.32 kernel won't spit anything out there.  I
> think shipping with a uEnv.txt that sets things to hd720 probably makes
> sense as connecting to an HDTV is probably one of the easiest options for a
> display.  I don't have an opinion on the consoleblank.
>

Dear Jason & Gerald,

If you are talking about the display power management , moving the
display into sleep mode after certain time , the below mentioned hack
worked for me

echo -n -e "\\033[9;0]" >/dev/tty0

>>
>> I'm not sure about the quotes and I haven't tried this.  I'll hook up a
>> board again here after tearing everything down for Indiana Linuxfest and
>> give it a shot.
>>
>> Regards,
>> Jason
>

--
Siji Sunny