Motherboard Wiring

Interface Diagram

Interface Description

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Pin Description

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Power Wiring

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Driver Installation

Motherboard Driver Jumpers

• STEP/DIR Mode. In this mode, microstepping is set using jumper caps, and current is adjusted via the potentiometer. The most common drivers requiring this are A4988, 8825. Consult the manufacturer's microstepping configuration table, then set the microstepping using jumper caps.

• UART Mode. The most common drivers using this mode are: TMC2208, TMC2209, TMC2226, etc. These driver chips can communicate asynchronously via UART with the main controller. Microstepping, run current, stealthChop mode, etc., can be set by modifying the configuration file.

• SPI Mode. The most common drivers using this mode are: TMC5160, TMC2130, TMC2240. Similarly, microstepping, run current, stealthChop mode, etc., can be set by modifying the configuration file.

  

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Driver Installation

• Drivers should be inspected before installation to avoid damage to the driver or motherboard.

• FLY Driver: If not using the infinite homing feature, set the DIP switch to position 1; conversely, if using the infinite homing feature, set the DIP switch to the ON position.

  
  dangerous

  • CAUTION!!! When installing the driver module, ensure the orientation is correct, i.e., the EN pin is in the top-left corner. Incorrect insertion may damage the driver or even the motherboard!!! Also, ensure proper heatsink attachment for the driver!!!
  

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Stepper Motor Wiring

• In 3D printers, the most commonly used is a two-phase, four-wire stepper motor. Its principle is shown in the diagram. There are two methods to identify the stepper motor wire sequence:

  1. Short any two of the four wires. Manually rotate the motor shaft. If the resistance is very high, these two wires belong to the same coil group, i.e., A+ and B+ or A- and B-. If it rotates as easily as when not shorted, they are not from the same coil group.
  2. Use the multimeter's continuity (buzzer) mode. Measure any two of the four wires. If the buzzer sounds, they are from the same group. If not, they are from different groups; replace one wire and measure again.
  
  

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Heater Cartridge Wiring

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Heated Bed Wiring

• AC Heated Bed: When wiring the solid-state relay (SSR), be careful not to mix up the input and output terminals.

  
  

• DC Heated Bed: When using the onboard MOSFET for a DC heated bed, pay attention to the power rating. The maximum current for a DC heated bed should not exceed 10A. If exceeding 10A, it is recommended to use an external MOSFET module for the heated bed to avoid irreversible damage to the motherboard.

  

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Thermistor Wiring

Thermistor Type Introduction

• The wiring method for thermistors is shown below. Consult the seller for the thermistor type.

• If purchased from FLY (as shown below), configure sensor_type as: ATC Semitec 104GT-2

  

• If using a standard NTC 100K (as shown below), configure sensor_type as: Generic 3950

  
  

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Motherboard Thermistor Wiring

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Fan Wiring

• Fan Wiring

  tip

  • The MOSFET must be installed.
  • Fan Wiring
  
  
  

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Endstop Switch Wiring

• Endstop switches have Normally Open (NO) and Normally Closed (NC) types. For 3D printers, it is generally recommended to use Normally Closed (NC). This way, if there is an issue with the endstop wiring, the system will promptly report an error, helping to avoid unnecessary crashes and printer damage.

  

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Bed Leveling Sensor Wiring

BL-Touch Wiring

• BL-Touch has five wires in total. The first group of three wires is responsible for sensor power and probe deployment/retraction. The second group consists of ground and signal wires, outputting the limit signal. When wiring BL-Touch, carefully verify the wire order. Incorrect wiring may permanently damage the sensor and motherboard!!! The wiring method is shown below.

  

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Klicky Wiring

• Klicky is a third-party bed leveling sensor that can be made at home at very low cost. It offers stable performance and high cost-effectiveness, and is recommended. The wiring method is shown below.

• Project Address: jlas1/Klicky-Probe

  

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Voron Tap Wiring

• Tap is a nozzle-based Z probe suitable for V2 and Trident printer designs. The entire toolhead moves to trigger an optical switch, offering better accuracy than regular endstop switches and compatibility with almost all printing surfaces on the market.

  warning

  It is not recommended to connect Voron Tap to 24V. Certain versions have a probability of burning out the Tap sensor when using 24V. This is not an issue with FLY products but a design flaw in Voron Tap. Please be aware!!!

  dangerous

  Note: Do not reverse the 5V and GND connections, as this may damage the Tap sensor or even the motherboard!!!

  

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FLY-Mini12864 LCD Wiring

• The diagram below shows the wiring method for FLY's mini12864. For screens from other manufacturers, please consult the respective manufacturer. Incorrectly connecting or reversing the Mini12864 screen may prevent the host from connecting to the MCU. If you could connect to the motherboard's MCU normally before using the mini12864 but cannot after connecting it, try disconnecting the mini12864 wiring!!!

  

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Connecting to the Host

• The motherboard connects to the host's USB port via a Type-C interface, or via a serial port. Only the former is described here.

  

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