M5Stack-ATOM image

M5Stack-ATOM

Development Board M5Stack_ATOM

M5Stack-ATOM is a development board based on the ESP32 microcontroller using XTENSA architecture.

This board features a maximum CPU frequency of 240 MHz and 4MB flash memory.

240 MHz CPU 4MB Flash WiFi + BT 4.2

About M5Stack-ATOM

ESP32 Xtensa dual-core 32-bit LX6 · 240 MHz

Ultra-compact ESP32 board with RGB LED and button - ideal for simple wireless triggers and automation nodes.

Technical Specifications

Complete technical specification details for M5Stack-ATOM

ESP32 · Dual-Core
Arch
XTENSA
Clock
240 MHz
Flash
4MB
Connectivity
WiFi
802.11 b/g/n (2.4 GHz)
Bluetooth 4.2
Classic + BLE
40
Digital IO
16
Analog In
14
PWM
16
Interrupts
Full datasheet & reference manual
Download

Quick Setup

Copy-paste configs for M5Stack-ATOM - auto‑generated from this board's exact hardware specs.

ESP32 240 MHz 4MB DIO Xtensa

In Arduino IDE 2 select M5stack Atom from the esp32 by Espressif package. In PlatformIO use board = esp32dev. ESP32 · 240 MHz · 4MB · DIO.

Tools menu settings
Board (select in Arduino IDE) M5stack Atom
CPU Frequency 240 MHz
Flash Size 4MB
Flash Mode DIO
Upload Speed 921600
Architecture Xtensa

In Arduino IDE 2, open Boards Manager, search "esp32" by Espressif and install it. Then go to Tools → Board and select "M5stack Atom" for the M5Stack-ATOM.

M5Stack-ATOM Pinout Diagram

Complete pin reference for M5Stack-ATOM

M5Stack-ATOM pinout diagram

Pin Mappings

Complete pinout and GPIO mapping for M5Stack-ATOM

40
Digital I/O Pins
16
Interrupt Pins
16
Analog Inputs
14
PWM Pins
PinAnalogTouchPWMOther
0G0
1PWMTX
3PWMRX
9PWMG9
10PWMG10
12PWMG12
19PWMG19 SS
21PWMG21
22PWMG22 SCK
23PWMG23 MISO
25PWMG25 DAC1
26PWMRXD2 SDA G26 DAC2
27PWMG27
32PWMTXD2 SCL G32
33PWMG33 MOSI
35ADC1
36G36 ADC2
37G37
39G39
Legend
A0 Analog input
T0 Touch sensor
PWM PWM capable
RX/TX Serial pins
LED Built-in LED
# Pin number

Default Tools & Configuration

Build and upload settings for M5Stack-ATOM

SettingValue
Bootloader toolesptool_py
Uploader toolesptool_py
Network uploader toolesp_ota
Bootloader address0x1000
Flash modedio
Boot modedio
Maximum upload size
1280 KB (1310720 bytes)
Maximum data size
320 KB (327680 bytes)
Configuration Summary

The M5Stack-ATOM uses esptool_py for uploads , esp_ota for OTA updates, and esptool_py bootloader at 0x1000.

Flash mode: dio | Boot mode: dio

Max sketch size: 1280 KB | Max data size: 320 KB