Can't force the resolution using disp_cap

Hi, followed the instructions to create the disp_cap file but it just doesn’t work, it just stays at the last resolution that i’ve set in kodi and not the one that i have in the file.

This has been an issue cause outta the box coreelec would go ‘corruped or black screen’ on my ancient 720p TV (it has 1080i but aparently didn’t help) and i managed to boot into kodi by changing this "vout=‘720p60hz’’ in coreelec/config.ini but if i change to any other resolution through kodi then it will boot with that one and not the one i’ve set in both files.

Also there’s resolutions that just go blackscreen / unsuported, is there any other way i can remove those and just leave “720p,1080p” ?

I’ve tried the stable / dev build and same issue.

Using the Vontar X4 4gb gbit.

Log:
https://paste.coreelec.org/MarryingVesta

Support for disp_cap was removed starting with the 5.4 kernel.

That’s a shame as my AM6B+ is often started with the TV OFF.

Is there any other alternative?

Why? AM6B(+) is S922X, Amlogic-ng, Kernel 4.9???

I thought S922X was supported in Amlogic NO version which does not use 4.9 kernel.

Hence no disp_cap would be an issue in NO on an AM6B+

Why NO on AM6B+? There is no DV support yet…
disp_cap is and maybe will not be supported anymore since 5.4

is disp_cap ‘feature’ dropped by the kernel itself (from the vendor)?
I have to use disp_cap hack as for some stupid reason my Samsung Q930b soundbar doesn’t properly passthrough all supported resolutions/rates from my TV (but they work just fine with disp_cap override obtained when tv was connected directly).
Will there be a replacement for such functionality?
Thanks!

Yes, was dropped by vendor kernel.
So you have two options

  • Change setup to connect box directly to TV, and soundbar via ARC to TV
  • Keep setup and use EDID Emulators
1 Like

thanks for clarification, might have to try eARC setup if/when the time comes.
Found a couple of threads in AVS forums regarding EDID handshake issues between older (pre 2020(1) models at least) Sony TVs and Samsung soundbars resulting in audio and video formats erroneously flagged as unsupported, so I’m probably a victim of that)

Well the solution for me was using the ng build instead of the ne, now i can use disp_cap fine, also tried the no build but not only i have no wifi but the resolutions still break like in ne.

FYI, you can also load your own EDID - some details on the approach here (basically need a bin edid file and can load into kernel):

And keep it loaded here:

2 Likes

awesome, thanks a lot! Looks like a cleaner and more future-proof solution (in case we’ll get the fully working 5.15/no kernel builds that don’t have disp_cap override sometime down the road).
I presume this override happens later in the boot process, so most likely no loading screen (but that’s a minor thing I can live with).

Yes, this is the issue I have. The EDID would be need in a very early state of booting to handle it correct. But in this stage there is no filesystem available to read the data from some place…

1 Like

Well after a few tries indeed the EDID Override worked perfectly but the problem was that i change monitors often so for example when i changed from my 1080i TV to a 720p monitor or even to a 2160p TV it would go black screen / colourful corrupted screen, i would need to change to a resolution also supported by the other monitor and for me that was just not very convenient.

Anyway what ended up working for me was removig / untick all resolutions using CRU ( Custom Resolution Utility 1.5.2 ) and then in “Extention blocks” changed the “CTA-861” to “Default”.

With this custom edid now all resolutions / refresh rates supported show and all of them function perfectly across my monitors / TVs, i still had to add " kernel_hdmimode=‘720p60hz’ " to the “config.ini” file in the “COREELEC” partition to make it work on my ancient TV.

Using stable omega NE build.

Here it is if you want a look at at it.
edited.bin (128 Bytes)

Edit :
Autostart file also needed.
autostart.sh (77 Bytes)

The EDID override also worked for me. Turned out boot animation also works (just need the TV to be turned on first, as when connected via soundbar it delays ‘ON’ until it’s already in Kodi UI).
Btw had to use the Deltacast E-EDID Editor, as the one from AW (v3.0.20) was bit buggy (at least for my EDID):

  • AW panicked about not enough memory in CEA block after adding a couple of resolutions, while Deltacast could add 3-4 more (and modded file didn’t have the warning when opened in AW afterwards)
  • AW had a bug where it could only add entries to YCbCr 4:2:0 Capability Map, but not remove (UI removed them, but after save and reopen the entries were back). Deltacast handled it correctly.
1 Like