Hi. Relatively new here, getting my bearings with forum content. I posted this question at the end of an old topic, but thought I’d try a new topic to see if anyone can help.
I’m putting together my own controller and display hardware. Running on a RPi 400 with a USB audio interface, I have an MCP23017 connecting the encoders and switches, and an ILI9341-based tft display.
The controller hardware is working. And, the display is generally working. There are pull-up resistors on the display backlight, so it’s on by default. However, when I connect the backlight pin to the RPi, the screen goes dark (making me believe the backlight pin is low). I’m using the rpi-display setting and overriding the backlight pin (the default had a compatibility problem with the audio (?)). Here’s the WebConf string I’m using:
Does anyone have an idea why the backlight isn’t working? Or, do I just misunderstand how it’s supposed to work?