Display HP S410u possible workling with RaspberryPi

[Mahdi2016]

Hi Michal,

I have built a new image, only with existing packages. I builded evdi module and evdipp without any problems.
The system is an up-to-date Raspian Jessi.

After testing the following commands, there was always the error message: *No usable EVDI found* (The evdi module under lsmod is active.)

Here is the output from 'example' command of the terminal window is at follows:

#as root:
Starting program: /bin/example /home/pi/EDIDv1_1440x900
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/arm-linux-gnueabihf/libthread_db.so.1".
[libevdi] ioctl: drop_master error=-1
Attempting to use device /dev/dri/card1...
[libevdi] ioctl: drop_master error=-1
Press Enter or Ctrl+C to quit...

#as user:
Starting program: /bin/example /home/pi/EDIDv1_1440x900
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/arm-linux-gnueabihf/libthread_db.so.1".
No usable EVDI found
[Inferior 1 (process 3898) exited with code 02]

No Screen showed up.

And the output from 'monitorsim' command of the terminal window is at follows:

#as root:
Starting program: /bin/monitorsim /home/pi/EDIDv1_1440x900
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/arm-linux-gnueabihf/libthread_db.so.1".
[libevdi] ioctl: drop_master error=-1
[libevdi] ioctl: drop_master error=-1
[libevdi] ioctl: drop_master error=-1
[libevdi] ioctl: drop_master error=-1
No protocol specified
QXcbConnection: Could not connect to display :0

Program received signal SIGABRT, Aborted.
0x75f89f70 in __GI_raise (sig=sig@entry=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:56
56      ../nptl/sysdeps/unix/sysv/linux/raise.c: No such file or directory.

#as user:
Starting program: /bin/monitorsim /home/pi/EDIDv1_1440x900
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/arm-linux-gnueabihf/libthread_db.so.1".
No usable EVDI found
[Inferior 1 (process 3864) exited with code 02]

The output from the "xrandr" is the same as in my last post.

I hope this information will help you.

Best regards
Michael

[mlukaszek]

Not being able to use evdi if not running as root is normal. (see note in https://displaylink.github.io/evdi/q...rt/#evdi-nodes)

Not seeing any extra output from "example" is also normal - but while the application is running, it should already be possible to check `xrandr` if you see DVI-*-* connector. Also, what `xrandr --listproviders` shows.

From what monitorsim run as root logs, I think you are running in ssh session, with no DISPLAY set. Run `export DISPLAY=:0` and try again...
Edit: on another look, it complains about not being able to connect to :0, so it might be something else...

Cheers,
Michal