I'm pretty sure that the little transistor you see on the i2c PCB next to the backlight jumper is for the backlight. It is driven from a spare pin on the i2c port expander.
You could PWM that GPIO by writing continuously to the port expander, or you could hack the PCB and drive the transistor from elsewhere.
Here's a representative schematic, which might match your board:
https://avrhelp.mcselec.com/index.html? ... cf8574.htm
You could PWM that GPIO by writing continuously to the port expander, or you could hack the PCB and drive the transistor from elsewhere.
Here's a representative schematic, which might match your board:
https://avrhelp.mcselec.com/index.html? ... cf8574.htm
Statistics: Posted by ame — Mon Sep 16, 2024 9:12 am