The last piece of missing hardware is finished. The picture below shows the 2nd RF to Zigbee gateway I had to make to be able to receive all the Hydronic balancing sensors I made earlier this week. One of those sensors just couldn’t make it through 3 walls all day long, so I created a temporary solution on a breadboard to solve this.
A very simple yet effective way (for me) to get the sensor data where I want it (in my Domotica system) with minimal effort.
The JeeNode runs a slightly modified version of the RF12Demo sketch made by Jean-Claude Wippler. I used the NewSoftSerial library to create an additional Serial port, and added a few print statements for the XBee port, right there where the RF12Demo Serial.println()’s the received RF data to the Serial port. Compile, Upload, setting the RF band, group- and node ID and I’m done!
This JeeNode is powered by a 5V USB adapter and the XBee gets its power from the 3.3V JeeNode ports. The XBee uses a Zigbee End Device AT firmware (2864) with the Sleep Mode set to Pin Hibernate. But because pin 9 is wired to GND, this means that the XBee is permanently on. Only 3 wires are needed to connect the XBee to the JeeNode: 3.3V, GND and a JeeNode digital pin to the XBee DOUT.
That’s it – moving on with where this all started with: understanding the flow of heating energy in our house!