In this part of the chapter, we are going to see what can go wrong when building M2M projects using Arduino.
The first thing that can happen is that the button is not correctly wired to the Arduino board. Make sure that you followed the wiring instructions. You can also check the lights on the Arduino board when you press the button: a light should turn on whenever the board is sending data, so this is what you should see when pressing the button.
One simple reason for this problem is that the humidity doesn't get low enough for the board to send an alert. What I recommend doing is checking the humidity level with the test sketch of the sensor. If needed, adjust the thresholds inside the code to make the board send correct alerts depending on the level of humidity you want for your plants http://www.kasetophono.com/2014/10/night.html.
