HELP - Can I change the use of unused pins?

[Lee]

It is currently using SKR1.4 as its main board.
This board supports up to two extruders, but I only use one extruder, so it’s HE01 heater output pin and
The filament sensor pin and HE01 heater temperature sensor are not currently in use.

Marlin Firmware uses a little bit of code to control the stepper motor cooling fan or heat sink fan, and I want to know how it can be used for clippers.

I hope you understand even if the writing is weird because it was written with a translator.

[Sineos]

You can use all pins on your board for different purposes. Depending on the pin on the MCU varying functions may be possible:

• All pins can be used as digital input, e.g. for switches or buttons
• Certain pins have an analogue digital converter (ADC) and can be used for, e.g. for measuring temperature
• Some pins are PWM capable, e.g. for controlling LEDs etc, but not for heater or fans because they do not have a MOSFET
• Some pins are PWM capable and have a MOSFET, which can be used for heaters or fans
• Then you have pins that have special bus functions like I2C, SPI etc

You need to consult the schematic of your board, e.g. BIGTREETECH-SKR-V1.3/BTT SKR V1.4-SCH.pdf at master · bigtreetech/BIGTREETECH-SKR-V1.3 · GitHub

Here you will find:

• HE1: PWM and MOSFET → Fans, Heaters, etc
• TH1: ADC → Measure analogue values
• E0DET: PWM but no MOSFET → LEDs or with an external MOSFET also fans or heater
• E1DET: Only digital

So if you want to connect a fan to HE1 for cooling your board, then the Klipper cfg will simply look like:

[controller_fan my_controller_fan]
pin: P2.4 #HE1 Pin
fan_speed: 1

[Lee]

thank you This is the feature I was looking for!