IntroductionThe µracoli team recently got one of the new RaspBee modules from dresden elektronik (DE) for evaluation. The RaspBee is a addon module for the popular Raspberry Pi computer and is equipped with an Atmega256RFR2. Due to its huge amount of RAM and FLASH and the integrated transceiver, this MCU is a smart choice for building ZigBee or IEEE 802.15.4 gateways.
The very popular Raspberry Pi needs probably no extra introduction. The credit card size ARM computer runs Linux (e.g. Raspbian) and it has USB and Ethernet interfaces, which makes it perfect for DIY projects.
Esentially the RaspBee consists of a radio module deRFmega256-23M12, is equipped with a ceramic chip antenna, the footprint for an U.FL coaxial connector, two LEDs and a (not populated) JTAG connector. The 12 pin header connects the RaspBee with the Raspberry Pi over the expansion connector. This connector provides power supply and serial port as well as one digital GPIO and the Reset pin.
The RaspBee is preprogrammed with a proprietary serial bootloader. For this bootloader, DE provides the tool GCFFlasher. It runs on the Raspberry Pi and provides a convenient and safe way to upgrade RaspBees firmware.
Caution: If you want to programm the RaspBee via the JTAG interface, the original DE bootloader firmware will be destroyed and because the flash protect fuses are set, there is no way to do backup in advance. The bootloader firmware makes the difference between the basic version (capable to handle 5 ZigBee nodes) and premium version (handles up to 200 ZigBee nodes). However upgrading the firmware with GCFFlasher is safe. You can always restore the firmware image from the DE download page.