I would suggest starting from a foundation others can replicate, removing that SPI display. In fact just having the GPIO reader app installed on a fresh Bookworm install. Check if that also exhibits the problem.The GPIO inputs are just switches, but there is also an SPI display involved.
I'd also ask what "flap" means and how that could be. It appears these switches use internal pull-downs.
Is the 'bcm2835' GPIO driver valid for Pi 4B under Bookworm ? I have no idea.
Statistics: Posted by hippy — Mon Jan 19, 2026 8:19 pm