Does anyone know how to properly configure 2 XBee (series 1) radios using XB24-DM firmware so a switch (say D1 set as input) to the first XBee can be output by the second XBee (say D1 as output HIGH)?
If you are not committed to XBee and just starting, I would recommend looking at Synapse Wireless RF Engines.
If you are talking sort distances through walls,
The code or rpc call if you want is fairly simple in python to accomplish what you want. If you are deeply committed to Xbee, I apologize, the rf engines are like the arduino of wireless communications. They have allowed me to quickly accomplish wireless projects.
If you need more range or lower power usage, go with something like:
The RF200 as 3 mile Line-of-sight range, walls will deteriorate the range, but they have plenty of range for your application.