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I wanted to implement the communication between the robot and the Cyclone II kit via ZigBee, but unfortunately I have never worked with this protocol ,nor do I have any idea how to implement the aforementioned in VHDL.
Any advice,tip,hint or any other kind of help will be much appreciated.
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Zigbee is a wireless protocol, so you will have to use some form of external PHY that translates from logic to RF. Most likely this PHY will have a parallel interface. Zigbee will have some form of protocol stack much like ethernet. Hence your system should look something like:
1) NIOS II processor running an OS, eg., Linux (NIOS with an MMU), uCLinux (NIOS without an MMU), or uCOS/II RTOS
2) A Zigbee protocol stack (Linux most likely has one)
3) An Avalon-MM slave component that maps the Zigbee PHY into the address map of the NIOS processor (which is an Avalon-MM master component). Probably DMA controllers to move packets to and from the Zigbee PHY (much like a network PHY would need).
4) Your board design; an FPGA, SRAM or SDRAM for the NIOS processor, Flash for the FPGA configuration and NIOS bootloader, kernel image, filesystem, etc., and the Zigbee PHY.
Sounds like a piece of cake, eh!
This is not really an FPGA application, its more like a microcontroller application. For example, Freescale has Zigbee micros:
http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=mc13212&fsrch=1&sr=1 Unless of course you are looking to create a Zigbee PHY in FPGA code along with ADC and DAC interfaces to convert to RF.
Cheers,
Dave