User Manual

80
Lesson 16 Potentiometer Module
Introduction
A potentiometer is a device which is used to vary the resistance in an electrical circuit without
interrupting the circuit.
Components
- 1 * Raspberry Pi
- 1 * Breadboard
- 4 * Jumper wires (Male to Male, 2 red and 2 black)
- 1 * Network cable (or USB wireless network adapter)
- 1 * Potentiometer module
- 1 * Dual-Color LED module
- 2 * 3-Pin anti-reverse cable
- Several Jumper wires (Male to Female)
Experimental Principle
An analog potentiometer is an analog electronic component. What’s the difference
between an analog one and a digital one? Simply put, a digital potentiometer refers to just
two states like on/off, high/low levels, i.e. either 0 or 1, while a digital one supports analog
signals like a number from 1 to 1000. The signal value changes over time instead of keeping
an exact number. Analog signals include light intensity, humidity, temperature, and so on.
In this experiment, PCF8591 is used to read the analog value of the potentiometer and output
the value to LED. Connect pin SIG of the potentiometer to pin AIN0 of PCF8591. Connect pin
R or Pin G of the Dual-Color LED to pin AOUT of PCF8591 to observe the change of LED.