Connecting a photoresistor to a microcontroller board port
This section shows how to connect a photoresistor to the Blue Pill and the Curiosity Nano boards to read the amount of light from an environment (for example, a living room).
In this section, we also explain how to use three LEDs to indicate that a room is well illuminated by turning a green LED on, that the light is dim by turning a yellow LED on, or that it is dark by turning a red LED on. The electronic circuit with the photoresistor sensor can be placed close to a plant and the circuit can be useful to know whether a plant needs more light or not. The next section shows how to build the circuit with the Blue Pill board.
Connecting a photoresistor to a Blue Pill board
The connection of a photoresistor sensor to a Blue Pill microcontroller board is simple. It can be directly connected to an input analog port, provided that you use a pull-down resistor. The circuit shown in Figure 4.4 describes how to do it, and it...