Problem with connecting monitor to DB 410c

Products Support DragonBoard410c
#1

Need Help!!! A few days ago got my DB, especially for this project bought the touchscreen display (ASUS VT207). After booting the DB the picture on the screen shifted to the left and blinks very fast left<->right. First thought was that problem with the board, connect the board to my desktop monitor it works well. Second thought: problem with the monitor… Connect the monitor to my desktop PC it works well…

It means somehow DB can not communicate properly with the monitor.

What could I do? Do I need some drivers for the monitor? If so, how could I install them?

Regards

George

#2

I could not find any Linux drivers for your multitouch monitor

However there are some posts of LinuxCNC users working with this display (so if you are using Linux I’d keep my hopes high):

my advice would be to just follow their recommendations.

#3

Drivers will be needed to get the touchscreen running but shouldn’t be needed to get the picture working. Are you using Android or Debian?

#4

I am using Android

#5

The display drivers for Android are hard coded to show video in HDMI mode at 1920x1080. Other video timings are possible but require you to recompile Android yourself and configure the video timings by hand according to this guide (the guide is for raw DSI because the display on DB410C is implemented using a DSI to HDMI bridge chip):

However before investing time in this I strongly recommend you test with Debian first to make sure there’s no additional problems with this hardware combination. Specifically, Debian uses a different display stack and supports both HDMI and DVI-D out-of-the-box. It should automatically select the native display resolution of the panel.

In fact you don’t even have to complete the installation of the debian image! The installer uses them same display stack as Debian so just attempting board recovery using the SD card method is sufficient (if you can see the installer then the hardware is OK together, no need to actually press the install button if you don’t want to):
https://www.96boards.org/documentation/ConsumerEdition/DragonBoard-410c/Installation/BoardRecovery.md

[Please copy and paste above link… oddly the link thumbnailer used by the forum software seems to find links to its own documentation problematic.]

#6

danielt Thank you for help, I will do my best to try all the possibilities. It takes time for me as I am complete newbie :slight_smile:

#7

The first step, testing with Debian, is done. The monitor was recognized properly, it means the problem is with communication with Android. So, I will move forward.

#8

I opened that pdf “https://developer.qualcomm.com/download/db410c/dsi-display-porting-guide-linux-android.pdf”,
it sounds for me as it is written in Chinese :-)…
Need more knowledge that I was expecting…

#9

It seems that I have to change something somewhere in LK and Android kernel. Should I open some files and change the parameters from 1920×1080 to 1600x900? After changing push that files through ADB back to the board?
Any explanation would be appreciated. Just a little path where to go…

Thanks
George

#10

To be honest I’ve never tried changing the output timings for Android. I think after looking at the doc that the key is getting the right info into the XML file (section 2.2.2) but if you’re not confident building Android from scratch I think you might struggle a bit.

#11

Hi George,

Were you able to change the output timings? I have the same problem and could really use your help…

Thanks.

#12

Hi Evez,

Unfortunately, I didn’t change the output timing and monitor still doesn’t work properly :frowning:
Because of the very busy time I put that project on hold. If you will find the solution for that problem please tell me, any help will be appreciated.

Regards
George