====== HowTo Run BLTouch connected to RPi microcontroller ======
==== Why? ====
  * 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?

==== Needed ====
  * BLTouch
  * a plier or smth to remove one pin from the dupon-connector

==== RaspberryPi as MCU ====
  * setup RaspberryPi as MCU following [[https://www.klipper3d.org/RPi_microcontroller.html|this guide]]

==== Attaching the BLTouch ====
  * remove the red pin from the triple-connection cable and put it into a single dupont case (included in original BLTouch packaging)
  * connect the pins to the [[https://pinout.xyz/|gpio pins]]:
    * white -> GPIO0
    * black -> GND next to GPI0
    * yellow -> GPIO27
    * brown -> GND
    * red -> 3.3V
    * //Todo: Add a picture of the wires//
  * you can choose whatever pins you like for control_pin, but it's easier to follow if you choose the same

==== printer.cfg adjustment ====
  * add the following to your printerconfig.cfg (also see the [[https://www.klipper3d.org/Config_Reference.html#bltouch|config reference]]
  * <file bash 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 
</file>

==== good choice for sensorpins ====
  * 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.
==== Testing the Probe ====
  * follow the [[https://www.klipper3d.org/BLTouch.html#initial-tests|official guide for testing the bltouch]]

==== Wrapping it up ====
  * replace your endstop_pin under [stepper_z] with <file>endstop_pin: probe:z_virtual_endstop</file>
  * set your correct nozzle offset following the [[https://www.klipper3d.org/Probe_Calibrate.html#calibrating-probe-z-offset|official guide]]