RGB LED

In this project, we will learn how to use Piper Make to light up the RGB LED.

RGB LED is equivalent to encapsulating Red LED, Green LED, Blue LED under one lamp cap, and the three LEDs share one cathode pin. Since the electric signal is provided for each anode pin, the light of the corresponding color can be displayed. By changing the electrical signal intensity of each anode, it can be made to produce various colors.

Wiring

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  • First find the longest pin (GND), there is only one pin (Red) on the left side of the longest pin, and two pins on the right side are Green and Blue.

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  • When using the same power supply intensity, the Red LED will be brighter than the other two, and a slightly larger resistor(330Ω) needs to be used to reduce its brightness.

  • The color ring of the 220Ω resistor is red, red, black, black and brown.

  • The color ring of the 330Ω resistor is orange, orange, black, black and brown.

  • The 3 buttons are used to control the lighting of the Red, Green and Blue LEDs respectively.

Code

After connecting Pico, click the Start button and the code starts to run. Pressing these buttons individually will emit a single color of light, but if two of the buttons are pressed at the same time, or all 3 buttons are pressed at the same time, the RGB LEDs will emit a variety of different colors, up to a maximum of 7.

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Note

In fact, RGB LED can emit up to 16 million colors, but since Piper Make does not have a block to output PWM signal, here we just use the [turn pin() (ON/OFF)] block to make RGB LEDs show 7 colors.

Code Explanation

You can think of this project as using three buttons to control the RGB LED, and setting three if judgment conditions to determine whether the three buttons are pressed or not. When the buttons are pressed, the levels of the corresponding pins are pulled high, causing the RGB LED to display different colors.