Wireless Sensors via ioBridge + ThingSpeak

I have had my ioBridge for a few years now, and recently wanted to expand the sensors to other parts of the house. After looking around at several different options, I picked up 2 netduinos (sparkfun ) and 2 xbees (sparkfun ). To go along with the netduinos, I picked up the following from ioBridge:

- 2 Temperature probes (http://store.iobridge.com/product_p/a0013.htm )

- 1 Light sensor (http://store.iobridge.com/product_p/a0011.htm )

-1 Serial smart board (http://store.iobridge.com/product_p/a0018.htm )


The netduinos have 2 UART serial connections per board. The netduinos also have 3.3V and 5V power, but the analog inputs can only handle 3.3V inputs. Luckily the ioBridge sensors can work with 3.3V. The XBEEs require 3.3V for power. I used series 1 XBEES, by default they act as a wireless serial cable. Basically, what ever goes in one XBEE comes out all of the others (and vice-versa).

For detailed information on programming the netduinos, check out the getting started guide on the netduino download page.

Step 1 The transmitter

Wiring up the transmitter:  I used a mini breadboard (you can find them on sparkfun) to share the 3.3V and ground.  Connect the ground of the sensor(s) to the same row, and then run a wire from that row to one of the ground pins on the netduino.  The netduinos have built in AREF so you don't have to worry about connecting that.  Do the same with the 3.3v, all on one row and connect to the netduino's 3.3V. I connected the analog output from the ioBridge sensors to the various analog inputs on the netduino.  The ioBridge sensors have their pinout printed on them.

I only needed 1 serial connection for the XBEE (to send data to the receiver).  Connect the XBEE to the 3.3V, Ground and Digital Pin 1 (UART 1 TX).  Digital Pin 0 is RX, if you would like to receive data.  You can find the pinout for the XBEE here .


Program the netduino: follow the instructions from their website (http://www.netduino.com/downloads/ ).  The netdinos use the .NET Micro Framework (which uses a compact version of C# or VB).  They have some code samples on their site, but I will attach the receiver and transmitter code on this instructable.
The main function of the transmitter polls the sensors every minute or so then broadcasts the data over the XBEE.  I send each sensor as a seperate string and the receiver parses all incoming sensor data