Wiring and Configuration

Buffer Internal Wiring Diagram

Installation Video

Buffer Connection to Mainboard and Configuration Method

Important Note

• The MMU Tool Board shown in the wiring examples below is for reference purposes only. When using in practice, you need to:

1. Connect the cables directly to the limit switch signal ports of your KLIPPER mainboard.
2. In the configuration file (such as printer.cfg), modify and match the port number configuration to ensure proper functionality.

Basic Functionality

• This buffer integrates filament runout detection and manual control functions:

• Filament Runout Detection (FILAMENT_SENSOR)

  • Signal Output: After a filament runout is detected, the buffer's PB15 pin outputs a low-level signal.

• Feed Button (FEED)

  • Single Press: The buffer's PA2 pin outputs a high-level pulse signal for 3 seconds.
  • Long Press: The buffer will perform a continuous feeding action until the button is released.

• Retract Button (RETRACT)

  • Single Press: The buffer's PA3 pin outputs a low-level pulse signal for 3 seconds.
  • Long Press: The buffer will perform a continuous retraction action until the button is released.

Wiring Guide

• When using the above functions, please refer to the following wiring diagram:

  

Important Note

• The MMU Tool Board shown in the diagram is for reference purposes only. When using in practice, you need to:

1. Connect the cables directly to the limit switch signal ports of your KLIPPER mainboard.
2. In the configuration file (such as printer.cfg), modify and confirm the port number configuration for PD3, PD4, and PD5 to ensure proper functionality.

Configuration Reference

MMU Tool Board Reference Configuration

[mcu LLL_PLUS]
serial:/dev/serial/by-id/usb-Klipper_stm32h723xx_12345-if00

[filament_switch_sensor Material_breakage_detection]
pause_on_runout: true
switch_pin: ^LLL_PLUS:PD3 # Replace with your actual pin
runout_gcode:
    PAUSE
    RESPOND MSG="material shortage"
insert_gcode:
    RESPOND MSG="Detected"
event_delay: 1.0
pause_delay: 0.5

[gcode_button Load_consumables]
pin:^LLL_PLUS:PD4 # Replace with your actual pin connected to the feed button
press_gcode:
    _Load_consumables

[gcode_button RETRACT]
pin:^!LLL_PLUS:PD5 # Replace with your actual pin connected to the retract button
press_gcode:
    _RETRACT

[gcode_macro CONFIG]
description: Extruder configuration
variable_extruder_temp: 200    ## Temperature
variable_extruder_length: 50   ## Length
variable_extruder_speed: 5    ## Speed (mm/s)
variable_extruder_time: 10    ## Time (s)
gcode:

[gcode_macro _Load_consumables]  ## Feeding
gcode:
    {% set temp = printer["gcode_macro CONFIG"].extruder_temp %}
    {% set length = printer["gcode_macro CONFIG"].extruder_length %}
    {% set speed = printer["gcode_macro CONFIG"].extruder_speed %}
    {% set time = printer["gcode_macro CONFIG"].extruder_time %}
    {% set feedrate = speed * 60 %}

    RESPOND MSG="Heat the extruder to {temp} °C"
    RESPOND MSG="Heat the extruder to {temp} °C"
    M109 S{temp}

    G4 P{time *1000}
    RESPOND MSG="Start feeding {length}mm"
    RESPOND MSG="Start feeding {length}mm"
    G91  ; Relative coordinate mode
    G1 E{length} F{feedrate} 
    G90  ; Absolute coordinate mode

    RESPOND MSG="Extrusion completed"
    RESPOND MSG="Extrusion completed"
    M104 S0

[gcode_macro _RETRACT]  ## Retraction
gcode:
    {% set temp = printer["gcode_macro CONFIG"].extruder_temp %}
    {% set length = printer["gcode_macro CONFIG"].extruder_length %}
    {% set speed = printer["gcode_macro CONFIG"].extruder_speed %}
    {% set time = printer["gcode_macro CONFIG"].extruder_time %}
    {% set feedrate = speed * 60 %}

    RESPOND MSG="Heat the extruder to {temp} °C"
    RESPOND MSG="Heat the extruder to {temp} °C"
    M109 S{temp}

    G4 P{time *1000}
    RESPOND MSG="Start material return {length}mm"
    RESPOND MSG="Start material return {length}mm"
    G91  ; Relative coordinate mode
    G1 E-{length} F{feedrate} 
    G90  ; Absolute coordinate mode

    RESPOND MSG="Return of materials completed"
    RESPOND MSG="Return of materials completed"
    M104 S0

Mainboard Reference Configuration

[filament_switch_sensor Material_breakage_detection]
pause_on_runout: true
switch_pin: ^PD3 # Replace with your actual pin
runout_gcode:
    PAUSE
    RESPOND MSG="material shortage"
insert_gcode:
    RESPOND MSG="Detected"
event_delay: 1.0
pause_delay: 0.5

[gcode_button Load_consumables]
pin:^PD4 # Replace with your actual pin connected to the feed button
press_gcode:
    _Load_consumables

[gcode_button RETRACT]
pin:^!PD5 # Replace with your actual pin connected to the retract button
press_gcode:
    _RETRACT

[gcode_macro CONFIG]
description: Extruder configuration
variable_extruder_temp: 200    ## Temperature
variable_extruder_length: 50   ## Length
variable_extruder_speed: 5    ## Speed (mm/s)
variable_extruder_time: 10    ## Time (s)
gcode:

[gcode_macro _Load_consumables]  ## Feeding
gcode:
    {% set temp = printer["gcode_macro CONFIG"].extruder_temp %}
    {% set length = printer["gcode_macro CONFIG"].extruder_length %}
    {% set speed = printer["gcode_macro CONFIG"].extruder_speed %}
    {% set time = printer["gcode_macro CONFIG"].extruder_time %}
    {% set feedrate = speed * 60 %}

    RESPOND MSG="Heat the extruder to {temp} °C"
    RESPOND MSG="Heat the extruder to {temp} °C"
    M109 S{temp}

    G4 P{time *1000}
    RESPOND MSG="Start feeding {length}mm"
    RESPOND MSG="Start feeding {length}mm"
    G91  ; Relative coordinate mode
    G1 E{length} F{feedrate} 
    G90  ; Absolute coordinate mode

    RESPOND MSG="Extrusion completed"
    RESPOND MSG="Extrusion completed"
    M104 S0

[gcode_macro _RETRACT]  ## Retraction
gcode:
    {% set temp = printer["gcode_macro CONFIG"].extruder_temp %}
    {% set length = printer["gcode_macro CONFIG"].extruder_length %}
    {% set speed = printer["gcode_macro CONFIG"].extruder_speed %}
    {% set time = printer["gcode_macro CONFIG"].extruder_time %}
    {% set feedrate = speed * 60 %}

    RESPOND MSG="Heat the extruder to {temp} °C"
    RESPOND MSG="Heat the extruder to {temp} °C"
    M109 S{temp}

    G4 P{time *1000}
    RESPOND MSG="Start material return {length}mm"
    RESPOND MSG="Start material return {length}mm"
    G91  ; Relative coordinate mode
    G1 E-{length} F{feedrate} 
    G90  ; Absolute coordinate mode

    RESPOND MSG="Return of materials completed"
    RESPOND MSG="Return of materials completed"
    M104 S0

Using Trigger Buffer for Feeding or Retracting

• Requires firmware updated to V1.1.0

• The buffer can automatically perform continuous feeding by detecting the following pin signal states:

• Automatic Feeding: When a low-level signal is detected on pin PB5, the buffer will perform continuous feeding.

• Automatic Retraction: When a low-level signal is detected on pin PB6, the buffer will perform continuous retraction.

Wiring Guide

• When using the above functions, please refer to the following wiring diagram:

Important Note

• The MMU Tool Board shown in the diagram is for reference purposes only. When using in practice, you need to:

1. Connect the cables directly to the limit switch signal ports of your KLIPPER mainboard.
2. In the configuration file (such as printer.cfg), modify and confirm the port number configuration for PB5 and PB6 to ensure proper functionality.

Configuration Reference

• Add the configuration
• Please note this configuration must be added after the basic functionality configuration is in place.

MMU Tool Board Reference Configuration

[output_pin _feeding]
pin:LLL_PLUS:PD6  # Replace with your actual pin
shutdown_value: 0
value:1

[output_pin _material_return]
pin:LLL_PLUS:PD7  # Replace with your actual pin
shutdown_value: 0
value:1

[gcode_macro Buffer_feeding]  ## Buffer feeding
gcode:
    {% set temp = printer["gcode_macro CONFIG"].extruder_temp %}
    {% set length = printer["gcode_macro CONFIG"].extruder_length %}
    {% set speed = printer["gcode_macro CONFIG"].extruder_speed %}
    {% set time = printer["gcode_macro CONFIG"].extruder_time %}
    {% set feedrate = speed * 60 %}

    RESPOND MSG="Heat the extruder to {temp} °C"
    RESPOND MSG="Heat the extruder to {temp} °C"
    M109 S{temp}

    RESPOND MSG="Start feeding {length}mm"
    RESPOND MSG="Start feeding {length}mm"
    SET_PIN PIN=_feeding VALUE=0
    G91  ; Relative coordinate mode
    G1 E{length} F{feedrate} 
    G90  ; Absolute coordinate mode
    G4 P{time *1000}

    RESPOND MSG="Extrusion completed"
    RESPOND MSG="Extrusion completed"
    SET_PIN PIN=_feeding VALUE=1
    M104 S0

[gcode_macro RBuffer_material_return]  ## Buffer retraction
gcode:
    {% set temp = printer["gcode_macro CONFIG"].extruder_temp %}
    {% set length = printer["gcode_macro CONFIG"].extruder_length %}
    {% set speed = printer["gcode_macro CONFIG"].extruder_speed %}
    {% set time = printer["gcode_macro CONFIG"].extruder_time %}
    {% set feedrate = speed * 60 %}

    RESPOND MSG="Heat the extruder to {temp} °C"
    RESPOND MSG="Heat the extruder to {temp} °C"
    M109 S{temp}

    RESPOND MSG="Start material return {length}mm"
    RESPOND MSG="Start material return {length}mm"
    SET_PIN PIN=_material_return VALUE=0
    G91  ; Relative coordinate mode
    G1 E-{length} F{feedrate} 
    G90  ; Absolute coordinate mode
    G4 P{time *1000}

    RESPOND MSG="Return of materials completed"
    RESPOND MSG="Return of materials completed"
    SET_PIN PIN=_material_return VALUE=1
    M104 S0

Mainboard Reference Configuration

[output_pin _feeding]
pin:PD6 # Replace with your actual pin
shutdown_value: 0
value:1

[output_pin _material_return]
pin:PD7 # Replace with your actual pin
shutdown_value: 0
value:1

[gcode_macro Buffer_feeding]  ## Buffer feeding
gcode:
    {% set temp = printer["gcode_macro CONFIG"].extruder_temp %}
    {% set length = printer["gcode_macro CONFIG"].extruder_length %}
    {% set speed = printer["gcode_macro CONFIG"].extruder_speed %}
    {% set time = printer["gcode_macro CONFIG"].extruder_time %}
    {% set feedrate = speed * 60 %}

    RESPOND MSG="Heat the extruder to {temp} °C"
    RESPOND MSG="Heat the extruder to {temp} °C"
    M109 S{temp}

    RESPOND MSG="Start feeding {length}mm"
    RESPOND MSG="Start feeding {length}mm"
    SET_PIN PIN=_feeding VALUE=0
    G91  ; Relative coordinate mode
    G1 E{length} F{feedrate} 
    G90  ; Absolute coordinate mode
    G4 P{time *1000}

    RESPOND MSG="Extrusion completed"
    RESPOND MSG="Extrusion completed"
    SET_PIN PIN=_feeding VALUE=1
    M104 S0

[gcode_macro RBuffer_material_return]  ## Buffer retraction
gcode:
    {% set temp = printer["gcode_macro CONFIG"].extruder_temp %}
    {% set length = printer["gcode_macro CONFIG"].extruder_length %}
    {% set speed = printer["gcode_macro CONFIG"].extruder_speed %}
    {% set time = printer["gcode_macro CONFIG"].extruder_time %}
    {% set feedrate = speed * 60 %}

    RESPOND MSG="Heat the extruder to {temp} °C"
    RESPOND MSG="Heat the extruder to {temp} °C"
    M109 S{temp}

    RESPOND MSG="Start material return {length}mm"
    RESPOND MSG="Start material return {length}mm"
    SET_PIN PIN=_material_return VALUE=0
    G91  ; Relative coordinate mode
    G1 E-{length} F{feedrate} 
    G90  ; Absolute coordinate mode
    G4 P{time *1000}

    RESPOND MSG="Return of materials completed"
    RESPOND MSG="Return of materials completed"
    SET_PIN PIN=_material_return VALUE=1
    M104 S0

Using MDM Sensor Wiring and Configuration

Function Overview

• When used with the FLY-MDM filament runout/blockage sensor, the buffer can detect extruder blockages.
• Requires firmware updated to V1.1.0.

Hardware Wiring

• The signal wire of the buffer should be connected to any unused general-purpose digital output pin on the mainboard, for example:

1. Connect the STEP pin of the buffer (PA5) to one of the mainboard's PWM, RGB, or 12864 pins. Note that the servo port of the BL-Touch can also be used.
2. Connect the DIR pin of the buffer (PB11) to a limit switch port on the mainboard.

• This connection is used to monitor the extruder motor's operational status, which is key to detecting blockages.

• When using the above functionality, please refer to the wiring diagram below:

Important Note

• The MMU Tool Board shown in the diagram is for reference purposes only. When using in practice, you need to:

1. Connect the cables directly to the limit switch signal ports of your KLIPPER mainboard.
2. In the configuration file (such as printer.cfg), modify and confirm the port number configuration for PD3 and PC0 to ensure proper functionality.

• MDM Reference Wiring

Configuration Reference

• Add configuration
• Please note this configuration must be added after the basic functionality configuration is in place.
• Please ensure that the STEP and DIR pins in the configuration below match the pins you are using.
• Also, other configurations must match your extruder configuration, or blockage detection may fail.

MMU Tool Board Reference Configuration

[extruder_stepper my_extra_stepper]
extruder = extruder
step_pin: LLL_PLUS:PE10
dir_pin: LLL_PLUS:PD4
rotation_distance: 17.472
gear_ratio:50:10
microsteps:16
full_steps_per_rotation: 200   

Mainboard Reference Configuration

[extruder_stepper my_extra_stepper]
extruder = extruder
step_pin: PE10
dir_pin: PD4
rotation_distance: 17.472
gear_ratio:50:10
microsteps:16
full_steps_per_rotation: 200   

Buffer Parameter Configuration

Get Serial Tool Assistant

• Connect the module to your computer using a USB cable, open the serial tool assistant, select the corresponding COM port, set the baud rate to 115200, and click Connect.

Notes

• If your extruder configuration does not include gear_ratio, set both driver gear teeth and driven gear teeth to 1.

Loading...

Parameter Description

Function Description	Configuration Command (Please enter in the serial tool)	Default Value	Unit	Notes
View all current parameters	Loading...	-	-	Send command to read all current configurations.
Set motor pulse count	Loading...	916	-	Set the number of pulses required for the motor to move per millimeter.
Set encoder detection distance	Loading...	1.73	mm	Set the filament movement distance represented by each encoder signal.
Set run timeout duration	Loading...	60000	ms	Set the auto-stop time in an untriggered state to prevent continuous extrusion.
Set error scaling factor	Loading...	2.0	-	Allowed error = encoder value X scale value. Example: 1.73 * 2.0 = 3.46 mm
Set speed control command	Loading...	260	mm	Set the buffer operating speed, maximum 600 (revolutions/minute), firmware needs to be updated to V1.1.1

Operation Notes:

1. Command Format: In the "Configuration Command" column of the above table, a full line of command (e.g., steps 916) is the content that needs to be fully entered.
2. Sending Method: Enter the command in the sending area of the serial assistant, then click Send.
3. Auto Save: Once the command is sent successfully, the parameter will take effect immediately and be automatically saved, no additional save operation is required.
4. Confirm Configuration: After modifying any parameter, send the info command to query all current parameters to verify whether the configuration is correct.