The Adafruit Gemma Wearables Starter Pack gets your first wearable project off to a flying start. The pack contains a GEMMA main board, 4 x RGB NeoPixel LEDs, 1 x coin cell battery holder with on/off switch, 2 x CR2032 coin cell batteries, a spool of thin, stainless conductive thread, a 20-piece needle set, a USB programming cable and a pack of 12 x crocodile clip test leads.
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 at 8MHz the board only draws 9mA when running. Compatible with the Arduino IDE although a couple of simple configuration tweaks are required. The 3 x GPIO pins can be configured to have 1 x analogue input and 2 x PWM outputs and 1 x hardware I2C bus as well as the normal digital IO functions.
The on board ultra-low dropout 3.3V power regulator supplies up to 150mA and will accept voltages up to 16V. It has reverse polarity, thermal cut-out and current limit protection. The board can be powered from either the USB or from an external source such as a battery and it will automatically switch from one to the other.
