I just ordered a couple of these:
http://www.sparkfun.com/commerce/produc … ts_id=8695
(don’t have them yet)
After reading the manual on them i’ve become a little confused. Are these strictly (if you’ll excuse my Wi-Fi lingo) infrastructure based or do they also support some form of “Ad Hoc”?
When i ordered them i just looked at 2mW vs. 1mW and didn’t even clue in to the “Series 2.5”, and SFE’s cookie cutter descriptions for items really don’t help.
I don’t know much about WiFi terminology so can’t relate there. But I do know some about XBees.
Digi Int has two different Hardware modules (1mW & 2mW) and four different protocols based on 802.15.4.
The Series 2 hardware can run either the Znet2.5 or the ZigBee protocols. Both of these require one node to be a Coordinator to create a ‘network’ of which other nodes can join.
Dig through or search this forum (Wireless/RF) for other threads on XBees. There is a recent thread on getting a pair of Znet XBees talking and should be very relavent to you.
Other threads have links to better documents and information that is easier to understand than the Digi docs. Also do download and read the documents on the Znet modules from Digi Int.
The series 2 modules are intended to be used only with Ember's ZigBee mesh routing protocol. Most simple applications should not use ZigBee's complexity and performance penality, so Digi XBee Series 1 is a better choice, sans ZigBee. I believe that Digi is contractually required by Ember to do ZigBee only on series 2. UNFORTUNATELY, resellers like SFE don't make series 1 vs 2 clear.danvm:
I just ordered a couple of these:http://www.sparkfun.com/commerce/produc … ts_id=8695
(don’t have them yet)
After reading the manual on them i’ve become a little confused. Are these strictly (if you’ll excuse my Wi-Fi lingo) infrastructure based or do they also support some form of “Ad Hoc”?
When i ordered them i just looked at 2mW vs. 1mW and didn’t even clue in to the “Series 2.5”, and SFE’s cookie cutter descriptions for items really don’t help.
With those (Freescale chip) modules, you can elect to do like WiFi’s ad-hoc mode, where each node specifies the destination address for each data frame, though the addresses are MAC addresses since IP is not use. It’s more like 802.3/ethernet MAC where you can (few do) send packets in a LAN based on MAC addresses or the broadcast MAC address. With XBee, this 802.15.4 mode has no pan coordinator, is a peer to peer network. You control everything, including if you wish, packet forwarding via whatever technique you wish, including, for immobile nodes, static forwarding address tables to build a cluster tree network in addition to simpler peer to peer addressing.
The difference between 1mW and 2mW, in a typical 80dB or more link budget, is negligible. There is a benefit to the XBee Pro modules with 60mW.
Cool, thanks for the replies, very helpful. I just received the units today and with a little poking around in X-CTU and a bit of reading i got these working pretty easily. I got them talking and even managed to reprogram my arduino over them, it’s actually not as bad as i thought it would be. but next time i think i’ll be getting some Series 1 pros. 
Quick question for y’all: anyone know of a quick and dirty way to get one of these to auto-reset an arduino without using the IO line passing? I cant seem to get it working, it just continually resets the board every .5 seconds, and the DTR pin on the shield doesn’t seem to do anything.
^^Nevermind, i got the reset working too, forgot to set the polling interval on the line passing. everything’s working great now.
Great.
Keep us updated on your project.