Onboard 5V Fan Port

The Pi board has an onboard controllable interface at 5V for main controller cooling, with the wiring method as shown below

Reference Configuration

[mcu host]                      # FlyOS has already generated the linux MCU for you by default, define it to use            
serial: /tmp/klipper_host_mcu 

[temperature_sensor FLY-π]      # Host machine temperature
sensor_type: temperature_host


[temperature_fan core_fan]      # Host machine cooling fan
pin: host:gpiochip1/gpio103     # Host machine fan pin
max_power: 1.0
sensor_type: temperature_host   # Set to host machine main controller temperature
control:watermark               # Control method
target_temp: 48                 # Host machine cooling fan start temperature
min_temp: 0                     # Minimum temperature, an error will occur below this temperature
max_temp: 90                    # Maximum temperature, an error will occur above this temperature
off_below: 0.10
kick_start_time: 0.50
max_speed: 0.8                  # Maximum speed, 80% of full power operation
min_speed: 0.3                  # Minimum speed, 30% of full power operation