HowTo Run BLTouch connected to RPi microcontroller

some printer board dont support the control signal for the bltouch, or need to remove some components. In this case you have to fiddle a little but it's possible, so why not?

BLTouch

a plier or smth to remove one pin from the dupon-connector

setup RaspberryPi as MCU following this guide

remove the red pin from the triple-connection cable and put it into a single dupont case (included in original BLTouch packaging)

you can choose whatever pins you like for control_pin, but it's easier to follow if you choose the same

add the following to your printerconfig.cfg (also see the config reference

printer.cfg

[mcu rpi]
serial: /tmp/klipper_host_mcu
 
[bltouch]
sensor_pin: ^rpi:gpio0
#   Pin connected to the BLTouch sensor pin. Most BLTouch devices
#   require a pullup on the sensor pin (prefix the pin name with "^").
#   This parameter must be provided.
control_pin: rpi:gpio27
#   Pin connected to the BLTouch control pin. This parameter must be
#   provided.
z_offset: 0.2
#pin_up_touch_mode_reports_triggered: False
#probe_with_touch_mode: True 

you can choose between gpio0 and gpio1 for the sensorpin because it has an inbuild pullup always active

klipper can't set pgios to pullup because of reasons

before i found this out, here was a long description how to set pullup by a script and make sure that this script runs always.

follow the official guide for testing the bltouch

replace your endstop_pin under [stepper_z] with

endstop_pin: probe:z_virtual_endstop

set your correct nozzle offset following the official guide