Adafruit gemma v2 miniature wearable electronic platform adafruit 1222 p the adafruit gemma v2 miniature wearable electronic platform takes small wearable microcontrollers to a new level of tiny measuring just 28mm across the board features a micro usb connector for power and programming a 2 pin jst battery connector a regulated power output 3 x gpio pads and an on off switch based around the super small attiny85 with 8kbytes of flash 512 bytes of ram and 512 bytes of eeprom running