After watching the ZigBee developments for a couple of months i decided i wanted to play with the IEEE 802.15.4 hardware myself. I wanted to avoid having to assemble the SMD RF boards myself, and i wanted a 2450 MHz chip. So i started looking for 2 x chips + discretes on board + antennae with an SPI interface for a reasonable price.

Note that the Zigbee specification is not published yet, and maybe it never will be published.

Pretty much all I could find on ZigBee is here. A table comparing the various chips is here.

Atmel (868/915 MHz only), ZMD (868/915 MHz only), UBEC and OKI are not actually selling chips or developer kits. This leaves Freescale, ChipCon and CompXS. The FreeScale board is pretty expensive : USD 150 for one board plus antenna, i'll be needing two of course. The FreeScale  PHY and MAC software software license is pretty restrictieve as well. CompXS seems pretty chaotic, no web shop, no fixed price (i've asked for a quote twice and was quoted two very different prices for the Outerside board). This leaves ChipCon : EURO 145,- for two CC2420EM + antennae + S&H + VAT. I asked about the software license for the MAC code in “CC2420DBK_Libraries_Release_1_1.zip“ and the answer was :

“The software included in our CC2420DBK_Libraries_Release are open source and fully available for everyone, and redistributing SW based on our examples are not a problem. However you should credit us by including comments that specifies that the code is basedin Chipcon examples.“

Fine with me.

For people interested in 802.15.4 MAC code :
From ChipCon : Library files and examples and light switch demo. No registration required.
From FreeScale : MAC / PHY Ref manual. MAC / PHY User Guide. No registration required
From FreeScale : Software MAC . Registration required.

For people interested in (pre -standard) ZigBee code :
From FreeScale : Z Stack v0.92. Registration required.
From Microchip : ZigBee stack for Microchip. Application Note. No registration required

I expect the boards end of Oktober (2004) and will be using two EtherNut boards to run the software on, and maybe later on a AVR Butterfly. I'll have a free and open source toolchain ( WinAVR ) and both NutOS and the CC2420 MAC / PHY code are more or less open source.

WinAVR is a more or less complete AVR development enviroment for Windows. ( haven't tried getting the debugger to work..) and pretty easy to install.

[1 Nov 2004]

The ChipCon boards have arrived. They are sold per pair, including antennae. The modules are really small and, besides the main chip, only have a small number of external components. The board is described here : CC2420EM Refrence Design. Next hurdle : try to get a matching connector for the tiny 20 pin 1.27 mm pitch headers (P1 and P2 on the PCB and schematic).

The connectors on the module are from Samtec and the connecor used has the part number SFM-110-02-SM-D-A-K-TR .

A matching connector is from the TFM series.

After that : a board to connect the CC2420EM to the EtherNut 1.3 .

[18 Dec 2004]

Microchip has announced a very nice ZigBee kit. 
“ The demonstration kit includes the ZigBee protocol stack and two PICDEM Z boards, each with an RF daughter card.”.
 The price is very nice as well : 199 USD. With FreeSacle and CompXS this will only buy you ONE RF board.

Microchip uses the same ChipCon RF chips.

[20 Dec 2004]

The SAMTEC connectors have arrived.

A zigbee news site is in the works.