Circuit Playground Express [Developer Edition]

The Circuit Playground Express is an all-in-one development board packed with sensors, LEDs, and a speaker — all on a round, beginner-friendly PCB with alligator-clip pads. No soldering required. It supports four programming environments: Microsoft MakeCode (block/JavaScript), CircuitPython, Arduino IDE, and code.org CS Discoveries.

Powered by an ATSAMD21 ARM Cortex-M0 processor at 48 MHz with 2 MB of SPI flash, the board plugs in via Micro-USB and shows up as a drive for easy drag-and-drop programming. It can also be powered by a AAA battery pack or LiPo battery.

Onboard Features

• 10× Mini NeoPixels – Individually addressable RGB LEDs
• Motion Sensor – LIS3DH triple-axis accelerometer with tap and free-fall detection
• Temperature Sensor – Thermistor for ambient readings
• Light Sensor – Phototransistor (also functions as colour and pulse sensor)
• Sound Sensor – MEMS microphone
• Mini Speaker – 7.5 mm magnetic speaker with Class D amplifier
• IR Transmitter & Receiver – Remote control codes, inter-board messaging, proximity sensing
• 2× Push Buttons – Labelled A and B
• 1× Slide Switch
• 8× Alligator-Clip I/O Pads – Analogue input, PWM output, I2C, UART
• 7× Capacitive Touch Pads – Plus 1× true analogue output
• Green Power LED & Red #13 LED
• Reset Button

Specifications

• Processor – ATSAMD21 ARM Cortex-M0, 48 MHz, 3.3V
• Flash Storage – 2 MB SPI (for CircuitPython code and libraries)
• USB – Micro-USB; acts as serial port, keyboard, mouse, joystick, or MIDI
• Power – USB, AAA battery pack, or LiPo battery

Ideal For

• Beginners learning electronics and programming
• Classroom STEM activities (MakeCode and code.org)
• Wearable and interactive projects (no soldering needed)
• CircuitPython and Arduino development

Resources

• Circuit Playground Express Guide
• Getting Started with MakeCode