ATmega128RFA1 Dev Board Hookup Guide
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About the ATmega128RFA1
The ATmega128RFA1 is a portmanteau of sorts -- two separate components combined to form one device. Half microcontroller, half RF transceiver.
ATmega128
Half of the ATmega128RFA1 is an ATmega128, an old mainstay of Atmel AVR microcontrollers. The 128 is an 8-bit microcontroller with 128kB of programmable flash, an abundance of I/O pins, an analog-to-digital converter, and much more.
Low-Power 2.4GHz Transceiver
The other half of the ATmega128RFA1 -- the "RFA1" part -- is what really makes it unique. That's because built into the chip is a 2.4GHz wireless radio transceiver. So one ATmega128RFA1 could talk to another up to about 75m away, at speeds of up to 2 Mbps.
Because it has built-in hardware support for IEEE 802.15.4, the chip can also talk to RF modules, like ZigBee's, Synapse modules, and IPv6/6LoWPAN devices. 802.15.4 defines a personal area network (PAN) of wireless devices. It's very similar to the Bluetooth standard (802.15.1) in that way. Unlike Bluetooth though, which can send data at around 3Mbps, 802.15.4 can't achieve as high a data rate, maxing out at around 250kbps. Still, 802.15.4 is an excellent, cost-sensitive choice when you don't need to quickly send huge chunks of wireless data.
In comparison to the other wireless standards and protocols out there, the ATmega128RFA1's transceiver is geared towards low-level, low-power, low-speed, low-data rate, low-range communication between devices. This isn't like WiFi, where we need to stream video, while downloading pictures of cats, and syncing our dropboxes. 802.15.4 is for sending data between embedded devices. Maybe you want to periodically transmit data from a weather station to a display in your house, or turn your coffee machine on from the bed. That's the type of situation 802.15.4 works best in! That sounds like a job for the ATmega128RFA1 Dev Board!