[RPi] Adding Custom Refresh Rates

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?

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.

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 enter

This 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!