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 Jumper

• 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 and 8825. Consult the manufacturer's microstepping configuration table and set it using jumper caps.

• UART Mode. The most common drivers using this mode are: TMC2208, TMC2209, TMC2226, etc. These driver chips can communicate with the main controller via UART asynchronous serial communication. 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 also 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 function, set the DIP switch to position 1. Conversely, if using the infinite homing function, set the DIP switch to the ON position.

  
  dangerous

  • IMPORTANT!!! When installing the driver module, ensure the orientation is correct, i.e., the EN pin is in the top-left corner. Incorrect installation may damage the driver or even the motherboard!!! Also, ensure a heatsink is properly attached to the driver!!!
  

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Stepper Motor Wiring

info

• Regardless of the manufacturer, a two-phase stepper motor ultimately has 4 wires. Regardless of color (black, white, green, yellow, etc.), they correspond to 4 wires. Therefore, we need to group the wires into two groups: A and B.
• For a two-phase, four-wire stepper motor, we don't need to know which group is A or B, as long as we identify the groups. The motor direction can be adjusted in the configuration.

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

  • Connect any two wires and manually rotate the motor shaft. If significant resistance is felt, the two wires belong to the same group. If not, they are not in the same group, and other wires need to be tested.
  • Use a multimeter set to continuity mode. Test any two wires of the stepper motor. If they are connected, they belong to the same group. If not, they are not in the same group, and other wires need to be tested.
  
  

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Heater Cartridge Wiring

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Heated Bed Wiring

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

  
  

• 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 it exceeds 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), set sensor_type to: ATC Semitec 104GT-2

  

• If using a standard NTC 100K (as shown below), set sensor_type to: 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 Wiring

• Endstop switches have two types: Normally Open (NO) and Normally Closed (NC). 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 potential damage to the printer.

  

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Bed Leveling Sensor Wiring

BL-Touch Wiring

• The BL-Touch has five wires in total. Three wires form the first group, responsible for powering the sensor and controlling the probe extension/retraction. The second group consists of a ground wire and a signal wire, outputting the limit signal. When wiring the BL-Touch, carefully check 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 a very low cost. It is stable and cost-effective, highly 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 precision than regular endstop switches and compatibility with almost all printing platforms 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 unplugging 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 it can connect via a serial port. Only the former is introduced here.

  

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