Monthly Archives: October 2011

A wireless lighting sensor network –

Our explorations with XBee radios continued this week, as we attempted to send readings from multiple photocells to a single base station that would then graph the results. Again, we ran into snags configuring the radios properly, overlooking the Destination High address, which set us back quite a bit. Playing with the sensors afterwards was fun, as always, though.

Single Lighting Sensor

Proceeding from the doorbell exercise, we built a simple “romantic lighting sensor” this week. One radio communicated values from a photocell that were then read through Arduino which sent a corresponding high or low signal to an LED based on an arbitrary threshold. Forgetting to set ATJV1 was our fatal flaw, as it took a lot longer for our radio to find its coordinator than it should have.

Building a radio-based doorbell

This week we finally got to get our hands dirty with XBee radios, tasked with setting up a simple radio-based doorbell. Generally, we were surprised at how un-smoothly the process went. It took us a good while to notice that my XBee radio was just one pin off while seated on its breakout board. After programming our radios to listen to each other, we also forgot to write the commands into firmware via ATWR, thus erasing our work. Working in a feedback light presented another round of troubleshooting various problems with loose wires and filled serial buffers. We ultimately failed in our quest to give the doorbell ringer a small pause before seeing the feedback light. On the whole, I have to say I now feel more adept with serial communication, though – and I’m impressed with the possibilities presented by the XBee radios.