User Manual

25
Lesson 1 Dual-Color LED
Introduction
A dual-color light emitting diode (LED) is capable of emitting two different colors of light,
typically red and green, rather than only one color. It is housed in a 3mm or 5mm epoxy
package. It has 3 leads; common cathode or common anode is available. A dual-color LED
features two LED terminals, or pins, arranged in the circuit in anti-parallel and connected by
a cathode/anode. Positive voltage can be directed towards one of the LED terminals,
causing that terminal to emit light of the corresponding color; when the direction of the
voltage is reversed, the light of the other color is emitted. In a dual-color LED, only one of the
pins can receive voltage at a time. As a result, this type of LED frequently functions as
indicator lights for a variety of devices, including televisions, digital cameras, and remote
controls.
Components
- 1 * Raspberry Pi
- 1 * Breadboard
- 4 * Jumper wires
- 1 * Network cable (or USB wireless network adapter)
- 1 * Dual-color LED module
- 1 * 3-Pin anti-reverse cable
Experimental Principle
Connect pin R and G to GPIOs of Raspberry Pi, program the Raspberry Pi to change the color
of the LED from red to green, and then use PWM to mix into other colors.
The schematic diagram of the module is as shown below: