The Adafruit Metro M4 Express AirLift combines the powerful ATSAMD51J19 ARM Cortex M4 processor with an on-board ESP32 WiFi co-processor — all in the standard Metro/UNO shield-compatible form factor. With 120 MHz clock speed, floating point support, and built-in TLS/SSL for secure connections, this board makes IoT projects fast and straightforward in both CircuitPython and Arduino.

The AirLift ESP32 co-processor handles WiFi communication over SPI, with pre-loaded root certificates and plenty of RAM for socket connections. CircuitPython's built-in JSON parsing and requests-compatible library make secure IoT projects remarkably easy to build.

Key Features

• ATSAMD51J19 Cortex M4 @ 120 MHz – With floating point and DSP instructions
• 512 KB Flash + 192 KB RAM – Ample space for complex applications
• AirLift ESP32 WiFi Co-Processor – TLS/SSL support with pre-loaded root certificates
• Native USB – Serial, HID keyboard/mouse support with no additional hardware
• 2 MB QSPI Flash – On-board storage for CircuitPython scripts or Arduino data logging
• 25 GPIO Pins – 8 analogue inputs, 2 true analogue outputs (DAC), 22 PWM outputs
• 6× Hardware SERCOM – Configurable as I2C, SPI, or UART
• Stereo I2S – Audio input/output with MCK pin
• Built-In Crypto – AES-256, true RNG, and public key controller
• UNO Shield Compatible – Standard Metro form factor
• Flexible Power – 7–9V DC (polarity protected) or Micro USB, with auto-switching and on/off switch
• UF2 Bootloader – Drag-and-drop firmware updates via USB storage mode
• Status LEDs + NeoPixel – Power, RX/TX, red LED, and RGB NeoPixel
• 3.3V Logic – All I/O at 3.3V

Ideal For

• Secure WiFi IoT projects with CircuitPython or Arduino
• Data dashboards and web-connected displays
• Projects needing high-performance processing with wireless connectivity
• Audio projects using I2S and DSP capabilities

Package Contents

• 1× Adafruit Metro M4 Express AirLift (WiFi) - Lite (fully assembled with headers)

Resources

• UF2 Bootloader Guide (Adafruit Learn)