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menkaur

Member

Registered: 2021-09-05

Posts: 5

How do I find id of display port on Samsung S34E790CN

I have Samsung S34E790CN monitor, connected to one GPU via Display port and to another GPU via HDMI.
I'm trying to query it's capabilities with `sudo ddcutil capabilities -v --display 2`. The result of this is as follows:

Feature definition file not found: SAM-SE790C-3069.mccs
Read cached capabilities string from /root/.cache/ddcutil/capabilities
Unparsed capabilities string:
Model: Not specified
MCCS version: Not specified
VCP Features:

The display reacts when I change it's brightness via `sudo ddcutil setvcp 10 $1 --display 2` so there is communication, I also found by trial and error the id of hdmi input, which is 5 (via `sudo ddcutil setvcp 60 5 --display 2`). Now, I have tried first 255 ids to check if any of those is the display port. None of them is. There are around 65000 ids that I could try to find out the correct one, but I see no way of automating this, since the command always returns 0, no matter if the id I supplied was correct or not

`sudo ddcutil getvcp 60 --display 2` produces

VCP code 0x60 (Input Source                  ): Invalid value (sl=0x00)

How do I get this done?

Last edited by menkaur (2022-08-27 05:02:49)

Lone_Wolf

Administrator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 15,060

Re: How do I find id of display port on Samsung S34E790CN

What is the output of

# ddcutil detect

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Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

clean chroot building not flexible enough ?
Try clean chroot manager by graysky

menkaur

Member

Registered: 2021-09-05

Posts: 5

Re: How do I find id of display port on Samsung S34E790CN

Never mind, I enumerated the last 256 items in the range and found the correct port. For anyone who ever needs it, the number is 65289. I'm going to post a bug to ddcutil about this