What is the minimum setup for an XBee unit on an Arduino. I have two ARduinos, and two XBees - I want to simple send serial commands back and forth - nothing complicated. That's it. Essentially what I am trying use one Arduino to toggle a relay on another system ran by another Arduino. Thanks
Brandon
All you need to add to what you have is two xbee shields, and some code.
I would like to try this without a shield. I have a height restriction on the project and would like to try to do this 'manually'. So what hardware is required to make the XBee and the Arduino play nice together 
I found this: XBee Adapter kit [v1.1] : ID 126 : $10.00 : Adafruit Industries, Unique & fun DIY electronics and kits
Which will do what I want - but I was thinking of implementing this myself.
Well if your arduino is 3.3v then you can do it slightly simpler than that but if it is 5v then you need a level converter that is on that board you linked to. Sparkfun also do one (in red!) but I think it may be slightly more expensive.
Mowcius
All you need to add to what you have is two xbee shields, and some code.
this was not true for me! My xbee (series 2) had to be flashed with X-CTU (windows only - ahrg!!) first. One as coordinator, the other as End-Device (although this was the default)
after that it worked for me..
Yeah often they do need to be flashed with X-CTU so a USB regulated board is useful.
Mowcius
this was not true for me!
That didn't involve extra hardware, did it? I thought that's what the OP was asking about.
I believe that if you have Series 2 (2.5) XBees, you will always have to change the settings on one of them so that you have a Coordinator.
With Series 1 XBees this is not necessary.
As for XCTU being Windows only, you should know that you can use a regular terminal program to change the XBee settings, using AT commands, and to save those changes to the XBee's memory, using ATWR.
If you have the board you need to make the connections that XCTU uses to change the settings, you can do this without using the XCTU. XCTU is really little more than a terminal program set up to make communication with the XBee simple. Other than updating the firmware itself, I don't think there's anything you do in XCTU that you cannot do as well through a terminal program.
I would like to try this without a shield. I have a height restriction on the project and would like to try to do this 'manually'
I can't help with the Arduino but I can help with the height. I make a kit that combines
an Arduino compatible board with an XBee. See http://tinyurl.com/5rfmrz
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