EasyLoader (beta)

Current Product Don't Have Test Firmware

Note: pls, use PC chrome/edge browser, if can't connect, refresh the webpage.

1. Click connect button

2. After connected successfully, pick a firmware

3. Click the burn button

4. After burning successfully, Unplug the device and restart.


StepMotor Driver



StepMotor Driver is adapted to M5 core series, the HR8825 chip solution provides a 3-way bipolar stepper motor control interface. You can implement independent control or multi-axis motor linkage after this module is stacked with M5 core series of the internal ESP32 generates signals directly to the driver chip.

This module integrated TCA9554 IO expansion chip provides 4 sets of input signal terminals + 3 sets of stepper motor subdivision control + 1 set of drive chip enable control, through the I2C interface control, can monitor and control the 8 expansion IO state, as well as for external limit switch, dynamic subdivision adjustment, motor braking. Integrated PWR485 communication interface (RS485 + 9-24V power input) and DC-JACK, which can be used for communication and more flexible power supply. Download the UIFLOW and you're ready to go!

With ESP32-GRBL firmware, web control. It can be easy to configure signal output and very useful when you need to position something very accurately. such as:printers, robotic arms, etc.

It is forbidden to plug or unplug the motor when it is powered on. All operations should be performed after the device is powered off to avoid damage to the module.

Product Features

  • Three-axis HR8825 stepper motor driver
  • Suitable for bipolar stepper motors
  • With current regulating potentiometer per circuit, drive current up to 1.5A
  • Support various subdivision modes, up to 1/32 STEP subdivision
  • Multiple signal input interfaces
  • PWR485 communication interface (RS485 + 9-24V power input)
  • DC-JACK terminal input (9-24V)
  • Built-in DCDC, integrated 9-24V to 5V circuit
  • Development platform.
    • Arduino, UIFlow


  • 1x StepMotor Driver
  • 4x 2.54-2P terminals
  • 3x 2.54-4P terminals
  • 1x 3.96-4P terminals


  • Printers
  • Scanners
  • CNC engraving machine control
  • Motion Module Control

Similar products comparison

Control method I2C communication Pulse signal
Firmware program Onboard STM32, built-in GRBL firmware No firmware, can be driven by ESP32 direct signal
Number of modules that can be stacked 2 1
Driver IC DRV8825 HR8825
Subdivision adjustment DIP switch TCA9554 chip control
Interface 3 groups of limit switch interfaces 4 groups of custom signal input interfaces + RS485 communication interface


Specifications parameters
Stepper motor driver chip HR8825
IO Expansion Chip TCA9554
Support for segmentation FULL、1/2、1/4、1/8、1/16、1/32
Maximum drive current per channel 1.5A
Input Signal Terminal Specifications 2.54-2P
Motor terminal specifications 2.54-4P
RS485 terminal specifications 3.96-4P
Net weight 40g
Gross weight 60g
Product Dimensions 54.2 * 54.2 * 13.2mm
Packaging size 95 * 65 * 25mm

Micro step truth table

M2 M1 M0 Resolution
0 0 0 FULL
0 0 1 1/2
0 1 0 1/4
0 1 1 1/8
1 0 0 1/16
1 0 1 1/32
1 1 0 1/32
1 1 1 1/32

TCA9554 Register

I2C Addr: 0x27

Use register 0x00 when reading status
Use register 0x01 when writing status
Configure the corresponding bit in register 0x02 to 1 to achieve polarity inversion, and configure it to 0 to not reverse Turn to
The corresponding bit in the register 0x03 is configured as 1 for input mode, and 0 for output mode.
The pin relationship corresponding to the above register bytes is shown in the table below.

Bit Desc R/W
7 P7 Subdivision adjustment bit M0 R/W
6 P6 Subdivision adjustment bit M1 R/W
5 P5 Subdivision adjustment bit M2 R/W
4 P4 DRV EN driver chip enable R/W
3 P3 input signal 3 R/W
2 P2 input signal 2 R/W
1 P1 input signal 1 R/W
0 P0 input signal 0 R/W

Drive current adjustment

The stepping motor has different specifications, and the required drive current may also be different. The current output can be adjusted through the metal knob on the module during use. In order to prevent the motor from overheating or damage, adjust the knob slowly during adjustment, observe the motor status or connect an ammeter to determine the appropriate drive current.

Pin Mapping

  • HR8825
CORE G16 G12 G15 G17 G13 G0
HR8825 X STP X / / DIR X / /
HR8825 Y / STP Y / / DIR Y /
HR8825 Z / / STP Z / / DIR Z
  • RS485
  • TCA9554



ESP32-GRBL & WEB-UI The program requires the use of ESP32 board management 1.0.3 version, which is higher It may not compile normally. Please refer to ESP32-GRBL-WIKI for instructions on use and WEB-UI control



Q1: How do I remove the speaker floor noise when the M5Core is on or running?

Execute the following statement in Setup() of the Arduino program

Q2: How does M5Core2 stack modules?

When M5Core2 is stacked with other M5 modules, you need to remove the battery base of Core2, which does not support module stacking.

Q3: A timeout error is displayed when uploading the program to the device

Reason and solution: The power supply current of the port is insufficient, which can cause the device to not enter the download mode normally. You can try to connect a capacitor (>0.1uF) between the RST pin and the GND pin, or when uploading the program, set the G0 Short-circuit to GND, so that G0 can be set to a low level state normally

Q4: How to solve the phenomenon of automatic signal triggering of M5Core button A

Add the header file #include <driver/adc.h> and the function adc_power_acquire(); in the Arduino program

Q5: M5 device battery life

The battery life of the controller is affected by various factors such as battery capacity, operating status, and load, so there is no fixed value. Reducing the load and adopting a sleep strategy can effectively increase the battery life.

Q6: Can multiple modules with batteries be stacked at the same time?

Support multiple stacks, the total capacity of the batteries in parallel increases, and the voltage remains unchanged. However, since the discharge of each battery is not balanced during use, there is a voltage difference between the batteries, which may cause the battery to charge backwards. .(will lose part of the battery capacity)

Q7: M5 master supports WiFi connection to 5G frequency band

ESP32 module currently does not support WiFi in 5G band, only 2.4G.

Q8: The RS485 device cannot communicate normally/data is garbled. Packet loss, etc.

Confirm whether the TX/RX pin on the TTL side of the pin is correct, try to add two 120Ω terminal resistors at the beginning and end of the device line to reduce signal reflection interference

Q9: The difference between different masters and camera products

Click the link below to view the product comparison table

Q10: M5 camera image blur, how to adjust the focal length

Rotate the lens to adjust the focal length within a certain range

Q11: The control RGB LED pin of FACE II BOTTOM conflicts with the I2S DOUT pin of CORE2


Q1: How to read the programmed firmware?

Use esptool to read the flash content of esp32 and export the bin file. Refer to the detailed operation

Q2: Several solutions for esp32 board download failure in Arduino IDE board management

Restart the Arduino IDE, the computer uses the mobile AP mobile network to download.

Method 3: Download the resource package provided by M5Stack for direct installation, and extract the contents to the board management path of Arduino, such as (C:\Users\Sean\AppData\Local\Arduino15\packages), https://m5stack.oss-cn-shenzhen.aliyuncs.com/resource/arduino/packages/m5stack_v2.0.0.zip
Q3: Arduino SPIFFS file upload operation

Refer to the Github link below, use arduino-esp32fs-plugin for file upload

Q4: When M5Burner burns firmware, an error pop-up window or exception occurs

Check if the COM of the corresponding device is selected and if the M5Burner is the latest version

Q5: Does the M5 master device support multi-language display (Chinese, English, Japanese, Russian, etc.)?

UIFlow users can switch the Label font to Unicode, Arduino users can use the Chinese font library provided in the M5GFX driver library

Q6: The program cannot load the SD card normally

Confirm whether the SD card format is FAT32, and no partitions exist.

Q7: How to use Bluetooth, HTTP, SD, WebServer, FreeRTOS and other features in Arduino IDE

You can refer to the following link for other ESP32 users to share the case program

Q8: How to download programs for STAMP C3U

STAMP C3U enters program download mode operation: 1. Long press the center button (G9) of STAMP C3U when the power is off. 2. Connect to the computer, after the port is successfully identified, program burning.

Q9: How STAMP C3U defines UART0 output mode

By default, USB CDC is not enabled, the serial port output started by C3U will be output through the default pins (G20, G21) of UART0. If you want to output through USB, please use the IDE to output Its USB CDC option is enabled. (Arduino users can enable it through Tools->USB CDC on Boot-Enabled. For IDF users, please refer to the ESP IDF official documentation.)

Q10: Unable to connect to UIFlow Desktop IDE

Refer to the UIFlow documentation of the corresponding device to check whether the device has entered the USB programming mode.

Q11: NBIoT devices cannot connect to the network normally

Make sure that the NBIoT used is not locked. Frequent device replacement or after activating the IoT card, using traffic in different places may cause the card to be locked. If the above situation occurs, please contact the IoT card supplier. If you are using the IoT card matching M5, please contact M5 after-sales through e-commerce or email. (provide the ICCID of the IoT card)


Q1: Consultation for after-sales problems of products

Describe the problems encountered in detail. Screenshots of the programs involved or files can be added as attachments and sent to M5Stack's official after-sales email

Q2: Code Resources, Cases, User Communication