Some output with ddcutil interrogate for Dell U3818DW

[kevin335200]

output.txt

[rockowitz]

Thank you for report.  It appears that the U3818DW is one of those monitors that never responds to a feature (getvcp) request with an indication that the feature is unsupported.  I've seen this before on inexpensive monitors, but never on a high-end monitor such as an Ultrasharp.    To confirm, can you run the following command and send me the output:   ddcutil getvcp 59 --trace ddc (I chose feature 59 because it's not in the listed capabilities and appears to have a garbage response.) Sanford

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On 02/02/2018 06:12 PM, 1kevin335200 wrote: output.txt <https://github.com/rockowitz/ddcutil/files/1691101/output.txt> — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#47>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ANhsbvQP1NV_KOPyB9Spkencj9Zm2hDeks5tQ5ZLgaJpZM4R35v_>.

[kevin335200]

Here it is:
output.txt

[kevin335200]

output.txt
This is the output of command "ddcutil getvcp known"

[rockowitz]

Looking at the DDC packet confirms that the "Unsupported VCP Code" flag is not set even though the feature is unsupported. Does this misinformation affect your use of ddcutil? Sanford

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On 02/03/2018 06:37 AM, 1kevin335200 wrote: Here it is: output.txt <https://github.com/rockowitz/ddcutil/files/1691698/output.txt> — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#47 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ANhsbt9OSMLhTF1016Arrx3I0N3qdCAiks5tREUPgaJpZM4R35v_>.

[rockowitz]

VCP feature group KNOWN includes all VCP codes for which ddcutil has a definition, i.e. all codes defined in the MCCS (Monitor Control Command Set) specs. In your case, "ddcutil getvcp known" tries to read each of the known features, and the monitor replies that is has a valid answer, even when the feature code is unsupported. VCP feature group SCAN, on the the other hand, includes all codes x01 to xff.

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On 02/03/2018 06:46 AM, 1kevin335200 wrote: output.txt <https://github.com/rockowitz/ddcutil/files/1691705/output.txt> This is the output of command "ddcutil getvcp known" — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#47 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ANhsbuASGlSL3PvYGljrjcktCpN-t87Vks5tREcMgaJpZM4R35v_>.

[kevin335200]

No. I only try using ddcutil to adjust brightness and volume and it works.
Thanks for the information, now i have learned a little more about it