I have just purchased a Rain sensor for 50 pence (UK money) - nothing right!

I have this idea about having a rain sensor outside and my HoCo system telling me (buzzers, strobes maybe even a voice command mmmm that is an idea) that it is raining after I have gone and put my washing out to dry!

This introduces a new type of sensor, namely, a non-fail-device. You see, all my sensors are in my system to tell me if something has happened (water too high, water too hot etc). Well this type of sensor (above) does not have a fail state. It only comes into play if another sensor and itself is in a certain state. For example if i have my washing out to dry AND if it is raining. So how can I achieve this. Well, simple really, as I have designed such a nice modular system. I will attach to a new project box a rain sensor and a couple of buttons and a couple of led lights.

This is how the sequence will work.

• I take the washing outside and put it on the line. I will press button A on the node.
• The node will send a msg to the server saying "button A on node09 has been pressed"
• The server will record the status of button a in the devices file. All is well!
• It starts to rain and the rain sensor sends a value to the node and the node sends a msg to the server ".. it is raining"!
• The server puts two and two together and if button a has been pressed it will send messages to buzzers etc

QED! (or have I missed something? - I always think this if something has worked out rather too easily!)