FireFly Badge is a light-weight, small and rechargeable mobile-senor networking platform.
The name comes from the fact that these devices can be embedded into ID cards, badges or made into smaller "cards" that can be inserted into mobile phones. The figure below shows the hardware platform next to its enclosure and a U.S. quarter dollar coin to facilitate size comparison.
The block diagram of the hardware is shown below. It consists of an Atmega1281 8-bit processor running at 7.37MHz and a Chipcon CC2420 802.15.4 radio. It has a USB interface for charging and connecting to a PC or a laptop. The device can also be charged using a DC wall adapter. It also has an
ADXL330 accelerometer that can detect motion. A 3.7V Li-Ion battery powers the device.