I'm looking to add both 640x480 and 1440x1080 resolutions at 72Hz & 96Hz each to my setup, for proper 24p cadence on my display. I tried adding just one resolution at a time in both cmdline.txt and config.txt and I can't see those as an option to whitelist. Can anyone please let me know how to add those as an option?
[RPi] Adding Custom Refresh Rates
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retrorgb -
October 21, 2025 at 6:33 PM -
Thread is Resolved
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You'll need to edit the EDID of your TV/monitor and add additional modes (and hope that your TV/monitor accepts those).
See eg here: RE: No HD Audio passthrough on Pi4
so long,
Hias
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That definitely worked and I confirmed that Kodi is even sending 24p sources in a proper cadence - Thank you very much!
I'm having an issue creating an EDID that supports multiple resolutions though. I'll keep trying and recruit some friends that have more experience in this, but at the moment, when I switch to a resolution that isn't 640x480, the screen gets cut off and the Pi is still actually outputting 640x480. I assume this is a mistake in my EDID creation, but I wanted to mention it, in case it's a Kodi-specific thing.
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Yup, the problem was me - All fixed. I attached what I created, in case anyone else wants to try. Here's basic instructions, but I'll have a video soon showing both how to do this, as well as why it's such a big deal for PC CRT monitor and projector users:
- Connect a working LibreElec/Kodi RPi setup to your network
- Go to Settings \ LibreElec \ Services and enable SSH
- Go to Settings \ System Info \ Summary to get your IP address
- Open a command prompt window, then ssh into the Pi via command line by typing: ssh root@ipaddress
- Enter the password
- Type "getedid create" and hit enter. LEAVE THE COMMAND WINDOW OPEN
- Use Filezilla (or your preferred software) to log in via SFTP-SSH
- Back out one directory, then navigate to /storage/.config/firmware/edid
- Delete the edid-HDMI-A-1.bin file (overwrite sometimes has issues, just delete it)
- Copy the unzipped edid-HDMI-A-1.bin file attached to this post to the directory
- Close filezilla
- Go back to the command prompt
- type "create-edid-cpio" and hit enter
- type "reboot" and hit enterThis will set the default resolution to 640x480 @ 60Hz, which basically everything should be compatible with. Then, change some Kodi settings:
- Settings \ Player \ Videos \ Adjust display refresh rate = Always
- Settings \ Player \ Sync Playback to display = Confirm it's OFF
(if you can't see these options, change the settings view in the bottom-left to "expert"Then back out to:
- Settings \ System \ Display = Select the preferred resolution and refresh rate.
If you ever need to revert the RPi, you can just SSH back in and run "getedid delete"
I still need to test audio and a few other things, but that should be enough to get my fellow CRT nerds up and running! -
HiassofT Is it possible to just add the 4:3 resolutions and 72Hz / 96Hz refresh rates to the whitelist of a nightly build? I'll happily throw a $100 sponsorship just to be able to test this feature and see if it works as good as I think it would.
I promise, I'm not asking just for my single use case! This would actually be a pretty big deal, as all the people doing the same thing these days either need to hunt down old video processors, or spend around $400 on modern scalers. I'll be doing a video similar to this one for the stuff I'm testing here:
External Content youtu.beContent embedded from external sources will not be displayed without your consent.Through the activation of external content, you agree that personal data may be transferred to third party platforms. We have provided more information on this in our privacy policy.While the main reason for asking is ease of use, I've also been having audio issues this whole time. Using the second HDMI port as audio-out almost never works and I even sometimes have issues with the audio on the main HDMI-out that's connected to an HDMI DAC. I don't have those issues without custom EDID's.
Here's the 4:3 resolutions people would need, with 640x480 and 1440x1080 being the most important:- 1440 × 1080 (1080p)
- 1280 × 960: SXGA
- 1152 × 864: XGA+
- 1024 × 768: XGA
- 800 × 600: SVGA
- 640 × 480: VGA
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The EDID "explain" what resolutions are supported by the display. If in the settings would be added some other (possible unsupported) resolutions, for other users could lead to blank screen and a lot of complains. At the other hand, if these resolutions it's added in the settings or coming from a modded EDID, probably wouldn't change anything. Instead of this, you should provide more informations about your "audio issues", maybe can be solved in other way, or check that modified "Player" and "System/Display" settings.
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I respectfully disagree. Adding a setting buried in an expert menu that's only going to be used by people who understand what they're trying to do (CRT & Projector use) isn't something that's going to cause problems for the average user.
Also, editing the EDID is a giant pain that most people aren't going to bother to do. Even people who'd like to make this work.
Please remember, I'm not just an end user asking for some random feature - I've spent over the last decade working with developers all over the world on retro gaming and retro video devices. I've had hundreds of conversations just like this one with dev's much smarter than me that just don't "get it". Eventually, some go to RetroRGB's site/channels and realize I actually know what I'm talking about, but most dismiss me just like you're doing.
So hopefully HiassofT will take me seriously and consider adding this even just to a private build I can test. If it works as well as I think, maybe these options can be added behind an "unsupported video modes" toggle or something? -
There isn't really anything we can do here.
Modifying EDIDs would be something that needs to be done deep down in the linux kernel and that has a high risk of breaking things - just look at the cheap chinese HDMI audio splitters which modify EDID on the fly and break stuff because they didn't get it 100% right.
Also adding modes that are not supported by a monitor may at best confuse users (I did a test with your EDID and my monitor didn't like 1440 × 1080 and 640 × 480 96Hz modes - signal out of range) or even worse interfere with kodi's whitelist because it may pick one of the additional modes instead of the actually supported modes reported by the display.
The way forward is that you create a curated, known working set of EDIDs that pepole can choose from - similar to what HDFury is doing, see eg https://hdfury.com/tools/HDfury_EDID_collection.zip
People can then pick one of those EDIDs that match their setup (eg either 1440x1080 or 640 × 480 96Hz), verify on their own that it really works with their display device and use one of the standard methods to inject it - either the edid override you get "for free" with linux, with an external "EDID fixer" device like the HDFury Dr.HDMI, VRROOM or similar ones, or by patching/reprogramming the HDMI sink (the latter would risky and often might not be possible to do though).
so long,
Hias
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I appreciate the detailed response Hias. I’ll see if I can come up with something to simplify things for installation before making the video.
Any suggestions for audio? Should I just try my best to create an EDID that also supports all audio modes? Then also assign it to both HDMI outputs? -
Audio is a bit tricky.
It's best to leave the EDID of the second HDMI port as is (using "getedid create" to fetch and force the EDID read from the AVR etc is fine), so it's using the info from the connected AVR/audio extractor/... - it you use some display mode not supported by the AVR, force some speaker allocation that doesn't match what's connected to the AVR etc things will go south.
For the EDIDs used by the first HDMI port / monitor it's best to create 3 different ones for 2.0, 5.1 and 7.1 setups (this is eg also what my HDFury VRROM offers in it's built-in EDIDs).
Enabling higher sample rates than 48kHz or compressed formats like AC3, DTS, MLP etc shouldn't hurt but keep in mind that there are audio bandwith limitations on the lower res modes. 720p50 and above will do 192kHz 8ch fine, but modes below are quite limited (eg 640x480p60 only allows up to 8ch 48kHz or 2ch 192kHz) - IIRC there's some info about that in HDMI or CEA specs.
If you use some HDMI audio extractor or similar (or even just a TV/monitor with audio capability) you'll also have to test if it actually works with the custom modes you added - some may only work fine with the standard HDMI modes but not with anything else.
so long,
Hias
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All great info, thank you. And you’re right, not all HDMI splitters and audio extractors work with odd timings…but luckily all the ones that work with odd retro gaming signals work with these. I appreciate the reminder though and I’ll make sure to mention that in the video.