Sensors

Sensors form a key role in the IoT space. These act as a kind of connection layer between the physical world and the digital world. The sensors coupled provide the entire system with the data that we want. Currently we aren't focused on industrial-grade sensors, but low-power sensors are suitable for small proof of concepts. When dealing with sensors, certain factors should be kept in mind:

• Power used by the sensor
• Type of output provided (digital or analog)
• Sensitivity of the sensor

The sensor usually performs one-way communication with the controller. The data captured by the sensors is converted into digital values using an ADC, and we obtain the output through a controller. Let's consider a use case of a light sensor. In this case, the sensor returns a calibrated value of the resistance. Thus we get a resistance value based on the light intensity. It is similar for other sensors, where any physical component is read and converted to a digital component. Normally a sensor has three pins; Vcc, Gnd, and signal. The interfacing of sensors with the controller will be discussed later in the chapter.