Expand description
LCD backlight on GPIO38, dimmed with LEDC PWM.
GPIO38 also switches power to the RGB LED. A WS2812 loses its state
whenever its supply drops, so any dimming below full brightness chops the
LED’s power at the PWM rate. Keep the backlight at Backlight::MAX
while using the RGB LED. (Inferred from the schematic and M5Stack’s docs;
not yet measured on hardware.)
The driver uses LEDC low-speed timer 0 and channel 0. Dropping a
Backlight leaves the PWM running at its last level.
Structs§
- Backlight
- Backlight brightness control.
- Backlight
Resources - LEDC peripheral and the backlight pin.
Constants§
- PWM_
FREQUENCY - PWM frequency: well above visible flicker and within 8-bit LEDC range from the 80 MHz APB clock.