BaseX is a special base compatible with LEGO EV3 motor. The structure design is similar to base26, supporting multiple ways of fixation, and an additional LEGO connection base is provided. When building the LEGO structure, Basex can be easily embedded in the work. Basex can be connected to 4-way (RJ11) LEGO motor at the same time, supporting angle / speed reading and control, and perfectly compatible with the original motor functions. In addition, the base provides two servo interfaces, which can directly control the rotation angle of the servo.There is a motherboard PDM microphone for sound collection. In order to adapt to different use scenarios, a UART interface (16 / 17) and a GPIO interface (26 / 36) are provided to make access to various sensors more flexible. A 950mAh battery is built in the base, which can be charged through the usb-c interface of m5core to extend the endurance. In order to improve the driving ability of the interface, the base is equipped with a DC power socket, which can be powered by an external 9-12v power supply to provide a stable power supply for the motor.

Product Features

  • 4-way RJ12 LEGO motor interface (total maximum output current 2A)
  • 2-way servo interface (total maximum output current 2A)
  • 1-way UART
  • 1-way GPIO
  • On board PDM microphone (GOIO 34)
  • On board DC-DC conversion (9 ~ 12V,independent power supply for the motor only)
  • Built in 950mAh battery
  • Multiple fixing methods / LEGO hole connection support


  • Encoder motor / servo controller
  • LEGO DIY intelligent control


  • 1x BaseX
  • 1x LEGO base
  • 2x M3 * 5mm 304 Stainless steel hexagon socket bolt
  • 2x M3 * 32mm 304 Stainless steel hexagon socket bolt
  • 1x HEX KEY


Resources Parameter
Net weight 59g
Gross weight 110g
Product Size 54*54*26mm
Package Size 150*65*40mm


download EasyLoader

  1. EasyLoader is a simple and fast program burner. Every product page in EasyLoader provides a product-related case program. This can be burned to the M5 device through simple steps, and a series of function verifications can be performed.

After downloading the software, double-click to run the application, connect the M5 device to the computer through the data cable, select the port parameters, click "Burn" to burn the program (For M5StickC, set the baud rate to 115200 or 750000)

  1. Before installing and using the Easyloader for M5Core, you need to install CP210X driver (you do not need to install with M5StickC as controller) Click here to download driver

I2C Control instructions

I2C Slave address: 0x22

Function Register address Value
SERVO2_ANGLE_ADDR 0x01 0~180
SERVO1_PULSE_ADDR 0x10 (uint16_t) 500~2500
SERVO2_PULSE_ADDR 0x12 (uint16_t)500~2500
MOTOR1_PWM_DUTY_ADDR 0x20 -127~127
MOTOR2_PWM_DUTY_ADDR 0x21 -127~127
MOTOR3_PWM_DUTY_ADDR 0x22 -127~127
MOTOR4_PWM_DUTY_ADDR 0x23 -127~127
MOTOR1_ENCODER_ADDR 0x30 int32_t
MOTOR2_ENCODER_ADDR 0x34 int32_t
MOTOR3_ENCODER_ADDR 0x38 int32_t
MOTOR1_SPEED_ADDR 0x40 -127~127
MOTOR2_SPEED_ADDR 0x41 -127~127
MOTOR3_SPEED_ADDR 0x42 -127~127
MOTOR4_SPEED_ADDR 0x43 -127~127

I2C Motor address:

Motor number Motor Address
MOTOR1 0x50
MOTOR2 0x60
MOTOR3 0x70
MOTOR4 0x80

Mode config method: Motor address + nByte

Byte Value
0 Run mode
1 position-p(3)
2 position-i(1)
3 position-d(15)
4 5
8 position-max-speed
9 speed-p
10 speed-i
11 speed-d
12 speed-point


Based on a LEGO NXT Mindstorm base for movement, and a M5Stack Grey Core for brains. Controlled by a simple web interface
Gate/door fingerprint security system with body temperature checks for the anti-COVID measure.
The PID Control Learning Platform is based on an M5Stack Fire & BaseX with TOF and Accel Units, and some Lego NXT parts.


Arduino IDE

Click here to download Arduino code


Click here to download UIFlow code