I have 2 GPIO/SPI touchscreens I'm trying to get working on my 3B - running Buster (10) for OctoPi (this is not so much an OctoPi question as I have another project in mind I wanna use my other display for)
I've not had a helluva lot of luck finding concise info online, so hoping to distil a TL;RD here
The latter actually gives me terminal output to the display (the Adafruit just a solid white screen). May need to check these again on a fresh install.
So far this is a not-to-bad result, IO to a TTY, but functionally limited, as at best I can get a res of 480x320
The intended application I need to use is OctoScreen, but (IINM) this uses a res of 640x480 (or was it 800x600?), so it scales out beyond the edges of the display.
The solution is to utilise the FrameBuffer driver to (scaled) mirror the HDMI output, and this is where I'm tripping up.
In the past, through trial & error, I've had limited success with this, so hoping someone here could help me with more a targeted & concise process for setting this up, as I've already tried a whole bunch of things that have not always worked well together & has severely muddies the waters.
Assuming that I have basic native display working (as per Adafruit/GoodTFT), what do I need to do next to:
- get HDMI-mirroring sorted via FrameBuffer driver?
- rescale the output to fit to the screen
- recalibrate touch input mapped to the video output
- Reduce resource footprint, so that means as skinny an X as I can get away with without the need for a full DE or web-browser
- bonus - screen-saver to prevent burn-in
- bonus#2: mapping GPIO pins on the one display