Display resolution Angstrom Demo


does anyone know where to get hold of the definative description of
which bootagrs to use with which kernel version and display driver.

There is so much on the web now which refers to old and new kernels
and drivers.

I have the Kernel 2.6.29

I am unable to change the display resolution.. Its keep defaulting the
640x480. I have tried all the different bootarg cobination on the web
but I think alot now refer to old versions.

My current setting is:

setenv mmcargs setenv bootargs console=ttyS2,115200n8 vram=12M
dvimode=800x600MR-24@60 omapfb.debug=y omapdss.def_disp=dvi root=/dev/
mmcblk0p2 rw rootfstype=ext3 rootwait

Would really help if there was a wiki page detailing the different
versions and the change in argumant names.



The documentation directory in the kernel source tree is the place to
get display info. It has a comprehensive description of DSS2 settings.
You can get kernel sources by installing OpenEmbedded, you will need
it sooner or later anyway.
I use this for display:
omapfb.mode=dvi:1280x1024MR-16@60 omapdss.def_disp=dvi


Hi Guys,

I am having real problems changing the Angstrom demo version display
resolution. I see from the web its a common problem/misunderstanding

I setup an SD card for the Angstrom demo 2.6.29-r37. Tried it out and
it worked on 640x480.

I wanted to change the resolution and tried allsorts of boot args. No
luck, Have read pages and pages from the web bit still no luck.

Anyhow I went though all the boot messages and realised the kernal
version was 2.6.28. the boot message was
Linux version 2.6.28-omap1 (koen@dominion) (gcc version 4.3.1 (GCC) )
#1 Tue Mar 24 18:57:27 CET 2009

But I downloaded the 2.6.29-r37 version??? not sure whats happening.

Anyhow, now I know the kernal version I realised the video arguments
change. So I am now trying the bootargs video=omapfb:mode:1280x1024@60
but still no luck.
( I did catch on one of the webpages that the resolution may be hard
compiled on the 2.6.28 kernel demo)

HAS anyone had anyluck changing the display resolution for the
Angstrom demo 2.6.28 kernel???
Am I correct that the Angstrom demo 2.6.29 is really a 2.6.28 kernel?
or have I screwed up somewhere??

Any help would be very much appreciated.




I am begining to see the light. Although this does not fix my problem

On the Angstrom demo link http://www.angstrom-distribution.org/demo/beagleboard/

uImage is actually uImage-2.6.28-r17-beagleboard.bin

I thought it would be the latest version.

Does this means that all I need to do is download uImage-2.6.29-r37-
beagleboard.bin onto my SD card and rename it uImage and I will have
the latest kernal for the demo???

Than maybe I can change the video resolution.

Anyone will to take the challange and guide me though the dark???




It worked I downloaded the uImage-2.6.29-r37-beagleboard.bin onto my
sd card and renamed it uIamge

The resolution is now much better.

PLEASE PLEASE can you update the uImage on the Angstrom demo link.

Oh but whats this. ON NO my usb keyboard and mouse do not work......

Sorry for the daley but I just had to pick myself off the floor after
the deep disappointment and dread at trying to figure this one out.

Anyhow, must not forget that lots of people are providing this code
for nothing. So you have to expect a few teething problems. (Thanks

Now to start again and try to get the keyboard/mouse working.

Anybdy any ideas.




Just plugged a new USB2 hub into the typeA USB connector on the
BeagleBoard C2 and it all works. This is brill.

Kids the lesson to learn is that.....

a) there is alot of stuff on the web about setting up BeagleBoard. But
remember alot of its for the earlier versions of the board and
b) Angstrom demo using kernel 2.6.28 has different boot arguments and
you cannot change the display resolution its stuck at 640 x 480. (Feel
free to correct me if I am wrong)
c) Angstrom demo using kernel 2.6.29 you can change the resolution but
you need an upto date uboot and certain boot arguments.
d) When you switch on if you press a key before the timeout this puts
you into uboot command line. You can use printenv to determine what
the non volatile boot arguments are.
e) You can use setenv to change boot arguments.

Remember though that whats on the web refers to kernel version before
2.6.29 and BeagleBoard version B. So always keep this in mind.

Now if you don't mind I am going to start trying to get the USB
peripherals working now.


Op 25 jul 2009 om 19:57 heeft melvin clarkson <mpclarkson@aspire-design.com > het volgende geschreven:\

b) Angstrom demo using kernel 2.6.28 has different boot arguments and
you cannot change the display resolution its stuck at 640 x 480.in

bzzzzzzt, wrong! You can change the resolution just fine using uboot or sysfs

...You just can't find working examples with GOOGLE...

The display variable is different in 2.6.27, .28 and .29. I haven't
bothered with .30 yet.

Resolutions seem to be specific for TV's and not standard VESA modes.

Waiting breathlessly to be proven wrong,
- dan

Op 26 jul 2009 om 14:47 heeft Dan Poirot <dtpoirot@gmail.com> het
volgende geschreven:\

...You just can't find working examples with GOOGLE...

sure you can, there have been numerous posts to this list detailing
the various differences. I've .28 specific args fly by last week.

You can change the resolution by change the bootargs variable during the boot time.
I was able to do it by changing this.



I guess I'm in line with all of you trying to find the proper kernel/
kernel command line parameters to get some decent video output from
the Beagle. I tried with some TVs as well as a monitor with varying
It's very strange that (at least for a rooky like me) it's not easy to
find default settings, which work out of the box.
Feel free to have a look at my experiments so far with the EBVBeagle:



The BeagleBoardUbuntu [1] and BeagleBoardDebian [2] pages on the
eLinux wiki have default settings that work for most DVI monitors.
Tomi was nice enough to point me to up-to-date documentation on DSS2
[3], so I've added a link on the FAQ [4]. When we finish updating
content for the upcoming ESC classes [5], I'll share what the bootargs
are that we'll use for the classes.

[1] http://elinux.org/BeagleBoardUbuntu
[2] http://elinux.org/BeagleBoardDebian
[3] http://gitorious.org/linux-omap-dss2/linux/blobs/master/Documentation/arm/OMAP/DSS
[4] http://elinux.org/BeagleBoardFAQ#.22DSS2.22_display_driver_for_.3E.3D_2.6.29
[5] http://beagleboard.org/esc

If you're using angstrom unstable you can do:

root@beagleboard:~# opkg install omap-dss-doc
Installing omap-dss-doc (2.6.29-r43.3) to root...
Downloading http://www.angstrom-distribution.org/feeds/unstable/ipk/glibc/armv7a/machine/beagleboard/omap-dss-doc_2.6.29-r43.3_beagleboard.ipk
Configuring omap-dss-doc

root@beagleboard:~# head /boot/DSS
OMAP2/3 Display Subsystem