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$46.22 |
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5.0 (2 reviews)

The Feather M4 Express is built around the ATSAMD51J19, a 120 MHz Cortex M4 processor with hardware floating point and DSP instructions, 512 KB flash, and 19...

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The Feather M4 Express is built around the ATSAMD51J19, a 120 MHz Cortex M4 processor with hardware floating point and DSP instructions, 512 KB flash, and 192 KB RAM. It ships with CircuitPython pre-loaded — plug it in and it appears as a small USB drive with main.py ready to edit. No installs, IDE, or compiler needed.

The board includes 2 MB SPI flash for storing CircuitPython scripts and libraries (or Arduino data files), a Mini NeoPixel, a prototyping area, and the UF2 drag-and-drop bootloader. It works with the Arduino IDE as well, and is compatible with all FeatherWings.

Key Features

  • ATSAMD51J19 Processor – 120 MHz Cortex M4 with hardware floating point and DSP, 3.3V logic
  • 512 KB Flash + 192 KB RAM – Substantial memory for complex applications
  • 2 MB SPI Flash – On-board file storage for CircuitPython scripts or Arduino data logging
  • CircuitPython Pre-loaded – Edit code directly on the USB drive, works on any computer
  • UF2 Bootloader – Drag-and-drop firmware loading; compatible with CircuitPython and Arduino IDE
  • Native USB – Built-in USB with bootloader and serial port debugging
  • Hardware Crypto – AES-256, true RNG, and public key controller
  • 21 GPIO Pins – 6× hardware SERCOM (SPI, I2C, Serial), 16× PWM, I2S input/output, 8-bit parallel capture
  • Analogue I/O – 2× 12-bit 1 MSPS DAC (stereo audio capable) and 2× 12-bit 1 MSPS ADC (6 analogue pins)
  • Mini NeoPixel – On-board addressable RGB LED
  • LiPo Battery Support – JST connector with built-in 100 mA charger and charging status LED
  • 32.768 kHz Crystal – For accurate clock generation and RTC
  • Prototyping Area – Small grid of through-holes for custom circuitry
  • Compact Design – 51 mm × 23 mm × 8 mm, weighing 5 g

Also Available

Ideal For

  • High-performance CircuitPython and Arduino development
  • Audio processing with dual 12-bit DACs
  • Portable battery-powered projects
  • Rapid prototyping with drag-and-drop programming

Package Contents

  • 1× Feather M4 Express (ATSAMD51)
  • 1× Header pin set
Note: LiPo battery and USB cable sold separately.

Jargon buster

Plain-language definitions for the technical terms used above.

ADC
An analogue-to-digital converter reads a changing voltage and turns it into a number the microcontroller can use. It matters when connecting analogue sensors such as light, sound, or variable-resistor sensors.
Bootloader
Small starter software on a microcontroller that lets new code be uploaded before the main program runs. Knowing how to enter bootloader mode matters when you need to program the board or recover it after a faulty sketch.
CAN bus
CAN bus is a reliable two-wire communication network originally designed for vehicles and now common in machinery and robotics. It matters when you need multiple controllers or devices to share status and control messages in a noisy electrical environment.
CircuitPython
A beginner-friendly version of Python designed to run directly on microcontroller boards. If a product supports CircuitPython, you can often program it by copying code files onto the board rather than setting up a more complex toolchain.
DAC
A digital-to-analogue converter turns numbers from the microcontroller into a real analogue voltage. It matters if you want to generate simple waveforms, audio-style signals, or variable control voltages rather than just on/off outputs.
GPIO
General-purpose input/output pins are microcontroller pins you can set in software to read signals, switch devices on and off, or connect to peripherals. The number of GPIO pins matters because it limits how many buttons, LEDs, sensors, and other parts you can wire directly to the board.
I2C
I2C is a two-wire communication bus used by many sensors and small modules. It matters because several I2C devices can share the same two wires, but each device needs a compatible address and your controller must support I2C.
I2S
I2S is a digital audio interface used to send sound data between chips, such as from a microcontroller to an audio amplifier or DAC. It matters if your project needs cleaner digital audio output than a basic buzzer or PWM signal can provide.
IDE
Short for Integrated Development Environment, a program used to write, run and manage code. It matters because some learners prefer a traditional coding workspace instead of a guided notebook-style lesson.
LED
A light-emitting diode is a small electronic component that lights up when current flows through it in the correct direction. In this kit, LEDs create the flashing effect, so polarity and correct soldering matter for the project to work.
LiPo
A lithium polymer rechargeable battery commonly used in portable electronics projects. It matters because LiPo batteries need correct charging circuitry and care, and this board includes hardware intended for that battery type.
native USB
Native USB means the microcontroller itself handles USB communication, rather than using a separate USB-to-serial chip. This matters for programming, debugging, and projects that need the board to act directly as a USB device.
NeoPixel
A type of addressable LED system where colour data is sent along a single digital data line from one LED or controller to the next. Compatibility matters because the timing and signal format must match for the lights or driver board to respond correctly.
PWM
Pulse Width Modulation is a way for a digital pin to simulate variable output power by switching on and off very quickly. It matters for controlling things like LED brightness, motor speed, or servo-style signals from a microcontroller pin.
RAM
RAM is temporary memory used while a device is running, and its contents are lost when power is removed. A “Run in RAM” mode is useful for testing settings without permanently programming the module, but it may not support every feature.
RGB
Short for red, green and blue, usually referring to an LED that can mix those three colours. It matters because controlling an RGB LED teaches how separate outputs combine to create different colours.
RTC
A Real-Time Clock keeps track of time even when the main processor is asleep or powered down, usually with a small backup battery. It matters for data logging and tracking projects that need accurate timestamps.
SPI
A fast serial communication bus often used for displays, memory cards, and sensors. It matters because SPI devices need specific pins for clock and data, plus a separate chip-select line for each device.

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