Wiring and Configuration

Buffer Internal Wiring Diagram

Installation Video

Buffer Connection to Mainboard and Configuration Method

Important Notice

• The MMU Toolboard shown in the wiring examples below is for reference only regarding interface definitions. When actually used, you need to:

1. Connect the cables directly to the endstop signal ports of your KLIPPER mainboard.
2. In the configuration file (e.g., printer.cfg), modify and confirm the port number configuration corresponding to PD3, PD4, and PD5 to ensure proper functionality.

Basic Functions

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

• Filament Detection (FILAMENT_SENSOR)

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

• Feed Button (FEED)

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

• Retract Button (RETRACT)

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

Wiring Guide

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

  

Important Notice

• The MMU Toolboard in the diagram is for reference only regarding interface definitions. When actually used, you need to:

1. Connect the cables directly to the endstop signal ports of your KLIPPER mainboard.
2. In the configuration file (e.g., printer.cfg), modify and confirm the port number configuration corresponding to PD3, PD4, and PD5 to ensure proper functionality.

Configuration Reference

Reference Configuration Using MMU Toolboard

[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 feed button
press_gcode:
    _Load_consumables

[gcode_button RETRACT]
pin:^!LLL_PLUS:PD5 # Replace with your actual pin, connected to 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="Heating extruder to {temp} °C"
    M109 S{temp}

    G4 P{time *1000}
    RESPOND MSG="Start feeding {length}mm"
    RESPOND MSG="Starting to feed {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="Heating extruder to {temp} °C"
    M109 S{temp}

    G4 P{time *1000}
    RESPOND MSG="Start material return {length}mm"
    RESPOND MSG="Starting 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="Material return completed"
    M104 S0

Reference Configuration Using Mainboard

[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 feed button
press_gcode:
    _Load_consumables

[gcode_button RETRACT]
pin:^!PD5 # Replace with your actual pin, connected to 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="Heating extruder to {temp} °C"
    M109 S{temp}

    G4 P{time *1000}
    RESPOND MSG="Start feeding {length}mm"
    RESPOND MSG="Starting to feed {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="Heating extruder to {temp} °C"
    M109 S{temp}

    G4 P{time *1000}
    RESPOND MSG="Start material return {length}mm"
    RESPOND MSG="Starting 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="Material return completed"
    M104 S0

Using Trigger Buffer for Feeding or Retraction

• Firmware needs to be updated to V1.1.0

• The buffer can automatically perform continuous feeding by detecting the level status of the following pins:

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

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

Wiring Guide

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

Important Notice

• The MMU Toolboard in the diagram is for reference only regarding interface definitions. When actually used, you need to:

1. Connect the cables directly to the endstop signal ports of your KLIPPER mainboard.
2. In the configuration file (e.g., printer.cfg), modify and confirm the port number configuration corresponding to PB5 and PB6 to ensure proper functionality.

Configuration Reference

• Add Configuration
• Please note that this configuration must be added after enabling the basic functions.

Reference Configuration Using MMU Toolboard

[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="Heating extruder to {temp} °C"
    M109 S{temp}

    RESPOND MSG="Start feeding {length}mm"
    RESPOND MSG="Starting to feed {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="Heating extruder to {temp} °C"
    M109 S{temp}

    RESPOND MSG="Start material return {length}mm"
    RESPOND MSG="Starting 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="Material return completed"
    SET_PIN PIN=_material_return VALUE=1
    M104 S0

Reference Configuration Using Mainboard

[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="Heating extruder to {temp} °C"
    M109 S{temp}

    RESPOND MSG="Start feeding {length}mm"
    RESPOND MSG="Starting to feed {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="Heating extruder to {temp} °C"
    M109 S{temp}

    RESPOND MSG="Start material return {length}mm"
    RESPOND MSG="Starting 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="Material return completed"
    SET_PIN PIN=_material_return VALUE=1
    M104 S0

Wiring and Configuration Method Using MDM Sensor

Functional Overview

• When used with the FLY-MDM filament runout/blockage sensor, the buffer can achieve blockage detection functionality.
• Firmware needs to be updated to V1.1.0.

Hardware Wiring

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

1. Connect the STEP of the buffer's 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 of the buffer's PB11 to the endstop port of the mainboard.

• This connection is used to monitor the working status of the extruder motor and is key to achieving blockage detection.

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

Important Notice

• The MMU Toolboard in the diagram is for reference only regarding interface definitions. When actually used, you need to:

1. Connect the cables directly to the endstop signal ports of your KLIPPER mainboard.
2. In the configuration file (e.g., printer.cfg), modify and confirm the port number configuration corresponding to PD3 and PC0 to ensure proper functionality.

• MDM Reference Wiring

Configuration Reference

• Add Configuration
• Please note that this configuration must be added after enabling the basic functions.
• Please ensure that the STEP and DIR in the configuration below are modified to match the pins you have wired.
• Also, other configurations must match your extruder settings; otherwise, blockage detection may fail.

Reference Configuration Using MMU Toolboard

[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   

Reference Configuration Using Mainboard

[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

Obtain via Serial Tool Assistant

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

Notes

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

Loading...

Parameter Description

Function	Configuration Command (Please enter in the serial tool)	Default	Unit	Notes
View all current parameters	Loading...	-	-	Send the command to read all current configurations.
Set motor pulse count	Loading...	916	-	Sets the number of pulses required for the motor to move one millimeter.
Set encoder detection distance	Loading...	1.73	mm	Sets the filament movement distance represented by each encoder signal.
Set running timeout duration	Loading...	60000	ms	Sets the auto-stop time in an untriggered state to prevent continuous extrusion.
Set error scaling factor	Loading...	2.0	-	Allowed error = encoder value × scale value. Example: 1.73 * 2.0 = 3.46 mm

Operation Notes:

1. Command Format: In the "Configuration Command" column above, the entire line of command (e.g., steps 916) must be entered completely.
2. Sending Method: Enter the command into the sending area of the serial assistant, then click Send.
3. Auto Save: After successfully sending the command, the parameters 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 and verify if the configuration is correct.