Setting up the hardware

About the hardware, there are at least two major issues to be pointed out:

• Power supply: We have two different voltages to use due to the fact the water pump, the lamp, and the cooler are 12V powered, while the other devices are 5V/3.3V powered. So, we have to use a dual output power source (or two different power sources) to power up our prototype.

• Interface: The second issue is about using a proper interface circuitry between the 12V world and the 5V one in such a way that it doesn't damage the BeagleBone Black or other devices. Let me point out that a single GPIO of the BeagleBone Black can manage a voltage of 3.3V, so we need a proper circuitry to manage a 12V device.

Setting up the 12V devices

As just stated, these devices need special attention and a dedicated 12V power line which, of course, cannot be the one we wish to use to supply the BeagleBone Black. On my prototype, I used a 12V power supplier that can supply a current till 1A. These characteristics should...