BeagleBone Black - No HDMI Output

I met similar issue as well. My monitor is ASUS LS221H which can correctly display outputted from my mobile phone Xperia Neo V via HDMI. From here, we can confirm the monitor and the cable both function well. After powering up, sometimes I could see the logo from BeagleBone Black. Then, what I could see is just no signal reported from the monitor.

I referenced the page,, and tried something described in the page via terminal
Followings are some information of my board.

root@beaglebone:/sys/class/drm/card0/card0-HDMI-A-1# xrandr --verbose
Screen 0: minimum 320 x 200, current 1280 x 720, maximum 2048 x 2048
HDMI-0 connected 1280x720+0+0 (0x42) normal (normal left inverted right x axis y axis) 474mm x 296mm
Identifier: 0x40
Timestamp: 1523547016
Subpixel: unknown
Gamma: 1.0:1.0:1.0
Brightness: 1.0
CRTCs: 0
Transform: 1.000000 0.000000 0.000000
0.000000 1.000000 0.000000
0.000000 0.000000 1.000000
1280x720 (0x41) 74.2MHz +HSync +VSync
h: width 1280 start 1720 end 1760 total 1980 skew 0 clock 37.5KHz
v: height 720 start 725 end 730 total 750 clock 50.0Hz
1280x720 (0x42) 74.2MHz +HSync +VSync *current
h: width 1280 start 1390 end 1430 total 1650 skew 0 clock 45.0KHz
v: height 720 start 725 end 730 total 750 clock 60.0Hz
720x576 (0x43) 27.0MHz -HSync -VSync
h: width 720 start 732 end 796 total 864 skew 0 clock 31.2KHz
v: height 576 start 581 end 586 total 625 clock 50.0Hz
720x480 (0x44) 27.0MHz -HSync -VSync
h: width 720 start 736 end 798 total 858 skew 0 clock 31.5KHz
v: height 480 start 489 end 495 total 525 clock 59.9Hz
640x480 (0x45) 25.2MHz -HSync -VSync
h: width 640 start 656 end 752 total 800 skew 0 clock 31.5KHz
v: height 480 start 490 end 492 total 525 clock 59.9Hz

root@beaglebone:/sys/class/drm/card0/card0-HDMI-A-1# parse-edid edid
parse-edid: parse-edid version 2.0.0
parse-edid: EDID checksum passed.

EDID version 1 revision 3

Section “Monitor”

Block type: 2:0 3:ff

Block type: 2:0 3:fd

Block type: 2:0 3:fc

Identifier “ASUS-LS221Hÿÿ”
VendorName “ACI”
ModelName “ASUS-LS221Hÿÿ”

Block type: 2:0 3:ff

Block type: 2:0 3:fd

HorizSync 31-81
VertRefresh 56-75

Max dot clock (video bandwidth) 170 MHz

Block type: 2:0 3:fc

DPMS capabilities: Active off:yes Suspend:no Standby:no

Mode “1680x1050” # vfreq 59.954Hz, hfreq 65.290kHz
DotClock 146.250000
HTimings 1680 1784 1960 2240
VTimings 1050 1053 1059 1089
Flags “+HSync” “-VSync”

Block type: 2:0 3:ff

Block type: 2:0 3:fd

Block type: 2:0 3:fc



Cloud9 GNOME Image 2013.06.20

root@beaglebone:~# cat /proc/cmdline
console=ttyO0,115200n8 video=HDMI-A-1::640x480@60 root=/dev/mmcblk0p2 ro rootfstype=ext4 rootwait

Finally, the three steps below work like a charm

root@beaglebone:~# export XAUTHORITY=ls /var/run/gdm/auth-for-root-*/database
root@beaglebone:~# export DISPLAY=:0.0
root@beaglebone:~# xrandr --output HDMI-0 --mode 1280x720 --rate 60

root@beaglebone:/sys/class/drm/card0/card0-HDMI-A-1# fbset

mode “1280x720-0”

D: 0.000 MHz, H: 0.000 kHz, V: 0.000 Hz

geometry 1280 720 1280 720 16
timings 0 0 0 0 0 0 0
accel true
rgba 5/11,6/5,5/0,0/0

After these, I do see the output on my monitor.

But anyone can tell me, if I tried
optargs=video=HDMI-A-1:1280x720@60 in uEnv.txt

The result is still no signal?


The display driver takes over once it is launched. It does not use the uENV.txt parameters. It uses the EDID.


Could be this the reason why I can have a perfectly working non-accelerated-android working on my BBB (followed, with Robert Nelson’s 3.8 kernel), while follwing these instructions I get a “Video format not supported” on my TV?

I’ve tried changing uEnv.txt, changing the resolution to a very standard one, and it looked like it was ignored… Is there any way to workaround this?


I’d like to see TI’s demo on my tv… even if it’s with the old kernel :slight_smile:

As I understand it, the SDK from TI has no support for the HDMI display. But, I would ask them and see what they say.


Yeah… it’s a bit confusing: their page actually makes you think they do have support for it. I’ll ask.
Thank you very much Gerald!

It does not. It was too complicated for them to do as I understand it. I think the EDID was a little overwhelming.


I’ve updated BBB using the newest firmware, BBB-eMMC-flasher-2013.09.15.img.
Still have the same problem.

OK. I would look at the cable. We have had several instances of people with bad HDMI cables.



I am having the same problems as described above.

The one difference I appear to be getting is that during the initial boot, I get the BeagleBone logo appear in the top left of the screen. This also changes size depending on what resolution I set in uEnv.txt

After this image disappears and a little more time has passed, I get “No Signal” on my 32" TV or “Power Saving Mode HDMI” on my LG Flatron L246WH 24" Monitor.

This suggests to me that the HDMI setup is working but something breaks it during the boot process.

Then your cable and board is fine. Make sure you have the latest SW.

And check