One of my go-to boards for sewable wearable circuits — the Adafruit Gemma M0 packs serious power into a 28mm round board designed to be stitched directly into garments, accessories, and interactive wearables.
Three large sew pads accept conductive thread or alligator clips, and the ATSAMD21 Cortex M0+ processor handles NeoPixels (8000+!), sensors, and CircuitPython with ease. Native USB means it shows up as a serial console, HID keyboard/mouse, or CircuitPython drive — no drivers needed.
Key Features
Processor: ATSAMD21E18, 32-bit Cortex M0+ @ 48MHz
Memory: 256KB Flash, 32KB RAM
3 × GPIO sew pads: analog input (12-bit), PWM, capacitive touch, I2C, Serial
One pad supports true analog audio output
Built-in RGB DotStar LED
Native USB — HID keyboard/mouse, serial console, CircuitPython drive
JST battery connector (3–6V input)
Reset + on/off switches
NeoPixel DMA support for buttery-smooth animations
CircuitPython & Arduino IDE compatible
Specs
Size: 28mm round × 6.4mm thick
Weight: 2.1g
Related products
Need a larger sewable board with more pins? Try the Adafruit Flora V3.
