Help Installing RPi Display Drivers for Info-Beamer OS

Hello everyone! I need help installing the drivers for a GPIO RPi display on the Info-Beamer OS. I’ve been able to use the screen without issue on Raspberry OS, but the Info-Beamer OS doesn’t allow me to install the driver due to missing dependencies like apt, cmake, and the tools necessary for installing fbcp.

The specific display I’m using is the 2.4inch RPi Display For RPi 3A+, which can be found here: 2.4inch RPi Display For RPi 3A+ - LCD wiki

To properly utilize this display, I need to run the script from this GitHub repository:

I’ve attempted to install the dependencies manually, but I’m encountering challenges due to the limitations of the Info-Beamer OS environment.

Any insights or suggestions would be greatly appreciated.
Thank you for your time and consideration.

Ey. That’s some crude installation script :slight_smile:

If that’s ever going to work, it will be quite fragile and might break at any moment in the future on a new OS release.

From what I understand in the installation script this works by using the tft9341-overlay.dtb file together with some kernel modules (which are unfortunately not bundled with the OS), these kernel module parameters. That probably create a frame buffer device in /dev/fb1. The Pi’s output is then configured to produce a 480x360 resolution output. That itself is still sent to HDMI, so fbcp (framebuffer copy, I guess) snapshots that output and places in the framebuffer in /dev/fb1, thereby making the output appear on the tiny screen.

You could maybe make that work by creating your own package service that loads the require modules (from the matching kernel version of the RPI kernel repository) and starts fbcp. You’d have to compile a binary for that (or maybe use the one bundled here?

Finally you’d have to copy tft9341-overlay.dtb to /config on the SD card and copy the config.txt values set here into /config/userconfig.txt.

That’s a pretty complicated process and has lots of opportunities to not work. And it will break immediately on any future OS update. I wouldn’t recommend it.

Thanks for digging into the script, I really appreciate you taking the time. The process does seem like a bit of a hack, I wish there was a more straightforward way to do it. I’ll give it a go and keep looking for alternatives. I really like Infobeamer, but it’s definitely a pain to get it working on these tiny GPIO displays.

GitHub - juj/fbcp-ili9341: A blazing fast display driver for SPI-based LCD displays for Raspberry Pi A, B, 2, 3, 4 and Zero seems to be an alternative method: From what I understand it circumvents the default linux kernel modules for such displays and instead does all that as a pure userland tool, thereby giving it more control over which pixels to update. So this might avoid adding extra kernel modules which are always a hassle.

The core idea is still the same: make the Pi output match the one of the tiny display, then start the program and have it shuffle around screen captures of the normal Pi output to the display. If you get that to compile and run on a Pi Zero, it should work on the info-beamer OS as well as it doesn’t seem to have any special library dependencies.

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