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.


Module NB-IoT



This is a wireless communication module, integrated an NB-IoT M5311 module that produced by China Mobile. The dimension if M5311 is 16mm * 18mm * 2.2mm, which is very tiny, and gives convenience to the user of more flexible dimension requirement.

package with LCC allows quick production through standard SMT, which provides a more reliable connection method and performance on the extreme environment.

the power requirement of this M5311 module is down to 2.1V, AA battery supported, it can fully utilize the power of AA battery, to provide an extremely low-power-consumption solution for terminal devices.

M5311 provides abundant external interfaces and protocol stacks, support peripheral sensors, etc.

Based on M5311, we have offered extra hardware resources on NB-IoT Module, WUP, STA LEDs, 3 alternative UARTs, one power button, and 2 alternative antennae.

Power Operation:

  • Power On: GPIO2 stay HIGH for 2s
  • Power Off: GPIO2 stay HIGH for 8s
  • Power On: Button long-press for 2s
  • Power Off: Button long-press for 8s
  • Reset module: GPIO26 HIGH

Product Features

  • Serial communication: UART
  • Product Power in : 5V
  • Serial Communication: UART2 16/17
  • 2x antenna: Spring / External
  • 1x Power Button
  • Nano SIM
  • M5311
    • Package: LCC
    • Frequency Band: B3/B8/B5
    • Tem:-40°C ~ 85°C
    • NB-IoT support LTE Cat NB2*
    • LTE Cat NB1 speed (kbps):
      • Single Tone:15.625(UL)/21.25(DL)
      • Multi Tone:62.5(UL)/21.25(DL)
    • SMS: PDU/TEXT mode
    • Network Protocol:
      • IPv4/IPv6/UDP/TCP/
    • Sensitivity:
      • Turn on retransmission :-130db
      • Turn off retransmission :-114db
    • power in:
      • 2.1V ~ 3.6V,Typ 3.3V (Low-Voltage version)
      • & 3.0V ~ 3.6V,Typ 3.3V (Fixed-Voltage version)
    • Consumption:
      • 3uA@PSM 0.4mA@ldle mode(DRx=1.28S)
      • 167mA@Tx(23dBm/15kHzST) 54mA@Rx
      • output power: 23dBm±2dB
    • Certificate: CCC/SRRC/NAL/GTI


  • 1x NB-IoT module


  • Smart Wearable device
  • Smart Parking
  • Smart Meter
  • IoT in City


Resources Parameter
Net weight 13g
Product Size 54.2*54.2*2.8mm
Package Size 60*57*17mm

Module compatibility

Master control device Compatibility
BASIC/GRAY/M5GO Compatible
FIRE Conflicts with PSRAM (G16/17), use requires flying leads to another set of UART pins
CORE2 Occupy external port G32

More info about NB-IoT: NarrowBand-Internet of Things (NB-IoT) is a standards-based low power wide area (LPWA) technology developed to enable a wide range of new IoT devices and services. NB-IoT significantly improves the power consumption of user devices, system capacity and spectrum efficiency, especially in deep coverage. Battery life of more than 10 years can be supported for a wide range of use cases.Supported by all major mobile equipment, chipset and module manufacturers, NB-IoT can co-exist with 2G, 3G, and 4G mobile networks. It also benefits from all the security and privacy features of mobile networks, such as support for user identity confidentiality, entity authentication, confidentiality, data integrity, and mobile equipment identification. NB-IoT focuses specifically on indoor coverage, low cost, long battery life, and high connection density. NB-IoT uses a subset of the LTE standard, but limits the bandwidth to a single narrow-band of 200kHz. It uses OFDM modulation for downlink communication and SC-FDMA for uplink communications

M5Stack Fire has occupied GPIO16 / 17 to connect with the PSRAM by default, it's conflict with TXD / RXD (GPIO16, GPIO17) of NB-IoT module. Therefore, when using the NB-IoT module with the M5Stack Fire, you might have to cut the TXD and RXD from NB-IoT module and wire fly to another set of UART pin

Some national carrier frequency bands

only for reference

North America B4 (1700), B12 (700), B66 (1700), B71 (600), B26 (850)
Asia Pacific B1(2100), B3(1800), B5(850), B8(900), B18(850), B20(800), B26(850),B28(700)
Europe: B3 (1800), B8 (900) , B20 (800)
Latin America B2(1900), B3(1800), B5(850), B28(700)
Commonwealth of Independent States B3 (1800), B8 (900), B20 (800)
Sub-Saharan Africa B3(1800), B8(900)
Middle East, North Africa B8(900), B20(800)


download EasyLoader

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

2.After downloading the software, double-click to run the application, connect the M5 device to the computer via the data cable, select the port parameters, and click "Burn" to start burning.

3.The CP210X (USB driver) needs to be installed before the EasyLoader is burned. Click here to download driver

Pin Map

M5Stack GPIO16 GPIO17 3.3V GND
Module NB-IoT RX TX 3.3V GND




Arduino IDE

To get complete code, please click here


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