No hdmi output.

Started by mr_rookes, February 12, 2017, 06:50:50 AM

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mr_rookes

I created a micro-sd with Debian Jessie for my A20-MICRO. After booting, I cannot get any output in my monitor. I connected by ssh with the unit, tried change_display.sh and got the message "Cannot find screen0_output_type variable!"
I suppose it can be a physical problem. What do you think?

JohnS

That looks to be a software problem.  Probably the sh script relies on not being run via ssh.

You _could_ also have a hardware ("physical") problem but I think you won't know till you fix the software one.

John

LubOlimex

Looking at the source code here: https://github.com/OLIMEX/OLINUXINO/blob/master/SOFTWARE/A20/A20-build-3.4.103/script_change_display_3.4.103/change_display.sh it looks like the shell script doesn't recognize any input for desired resolution. Probably the SSH input is not well-received by the board.

Technical support and documentation manager at Olimex

mr_rookes

I haven't work on it until now.
I got the change_display to work by disabling audio with a kernel arg.
But still no signal in the monitor :(

LubOlimex

Normally, you don't even need to run the config script. Official images provided by Olimex should have HDMI set as default output.

Are you using an official image? Did you test with this one: https://www.olimex.com/wiki/images/7/78/A20_OLinuxino_Micro_debian_Jessie_34_103_2G_release_12.torrent

Does your monitor have native HDMI or you use an adapter?

Best regards,
Lub/OLIMEX
Technical support and documentation manager at Olimex

mr_rookes

I am using an official image and an adapter. No native hdmi in the monitor. I tried an adapter without extra USB power and another one with extra power. None of them would provide signal to the monitor.

LubOlimex

Probably the adapter is the root of the problem. The adapters might mess with the signals - the timing and the levels are important.

Unfortunately, there isn't much else to recommend, except testing with another monitor with native HDMI. We haven't used adapters and I can't recommend any adapter.

Best regards,
Lub/OLIMEX
Technical support and documentation manager at Olimex