XC4414
This is the most breadboard friendly Arduino™-Compatible device you will find. Despite its small size, it packs virtually all the features of the full-sized development boards into a tiny DIP-style board that drops directly into your breadboard. It uses exactly the same ATMega328 chip as its larger cousins, so there is no need to change any of your coding. A Mini-B-USB port is easily accessible on top of the board for programming and serial communication.
Specifications
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