Wade made a tiny Arduino compatible board. It has 8 Digital I/O pins, 4 Analog pins, and an on-board lipo charger. The ATmega32U4 microcontroller has more memory than the original Arduino.
Digital pins 0-7, Analog 2-5, and a RST, V+, and GND pin are broken out to two rows of pins, maintaining about half the pins in a familiar shape and organization. A JST connector for LiPo batteries like the ones available through SparkFun and Adafruit and an MCP73811/2 charger circuit makes the Demiduino well suited for portable applications. On the back, I’ve also included CR1225 clips for ~3v3 power from easy to find coin cell batteries, and a power switch to save battery life.
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