Adafruit GEMMA v2 Wearable Electronic Platform

Adafruit GEMMA v2 Wearable Electronic Platform is a bite-sized tiny wearable platform board in a 1" diameter package. It's powered by an Attiny85 and programmable with an Arduino IDE over USB. This microcontroller board is small enough to fit into any project. Adafruit GEMMA v2 Wearable Electronic Platform features a Micro-B USB connector and an On-Off switch.

Even though designers can program GEMMA using the Arduino IDE, it's not fully 100% Arduino-compatible.

• GEMMA does not have a serial port connection for debugging, so the serial port monitor will not be able to send/receive data
• Some computer USB v3 ports do not recognize GEMMA's bootloader, so designers will need to use a USB v2 port or a USB hub in between

Features

1.1"/28mm diameter and 0.28"/7mm thick
Sew or solder into wearable projects
ATtiny85 on-board, 8K of flash, 512 bytes of SRAM, 512 bytes of EEPROM
Arduino compatible
Hardware I²C capability for breakout and sensor interfacing
Internal oscillator runs at 8MHz
Draws only 9mA while running

Micro-USB jack for power and/or USB uploading
Rugged and foolproof bootloader process
~5.25K bytes available for use (2.75K taken for the bootloader)
On-board 3.3V power regulator with 150mA output capability and ultra-low dropout
Power with either USB or external output (such as a battery)
On-off switch
Reset button