View source for Experiment 2: RGB LED Light Experiment

*[[Basic Experiment Kits For Arduino]]
*[[Basic Experiment Kits For Raspberry Pi]]
== Arduino ==
=== Experimental Phenomenon ===
*Implementation of Cool Lighting Effects with RGB Module

=== Experimental Principle ===
*By adjusting the intensity of the three primary colors (red/blue/green) through PWM voltage input on the R, G, and B pins, a full-color mixing effect can be achieved.

=== Circuit Connection ===
*[[File:实验二：RGB彩灯实验_接线1.png|400px]]

=== Reference Program ===
<pre>
int red = 3;    //select the pin for the red LED
int green = 5;  // select the pin for the blue LED
int blue = 6;   // select the pin for the green LED
int val;

void setup() 
{
 pinMode(red,OUTPUT);
 pinMode(green,OUTPUT);
 pinMode(blue,OUTPUT);
}
void loop() 
{
  for(val=255; val>0; val--)
   {
     analogWrite(red,val);
     analogWrite(blue,128-val);
     analogWrite(green,255-val);
     delay(1); 
   }
  for(val=0; val<255; val++)
   {
     analogWrite(red,val);
     analogWrite(blue,128-val);
     analogWrite(green,255-val);
     delay(1); 
   }
}
</pre>
== Raspberry Pi ==
=== Circuit Connection ===
*[[File:实验二：RGB彩灯实验_接线2.png|600px]]

=== Program Execution ===
==== Python ====
* Install the gpiozero library
** You can use the following commands to install the library:
<pre>
sudo apt update
sudo apt install python3-gpiozero
</pre>
:* For other systems on the Raspberry Pi, you can use the following command to install the library:
<pre>
sudo pip3 install gpiozero
</pre>
:* Run the following command to view the GPIO pin definitions on the Raspberry Pi:
<pre>
pinout
</pre>
*Download the Raspberry Pi reference examples, unzip the files, copy them to the user's home directory, and run:
<pre>
cd /home/pi/raspberrypi/2/python_gpiozero
python RGB.py
</pre>
*You should see the Raspberry Pi running the RGB program correctly. To interrupt the program, press ctrl+C.
*Command description: '''gpiozero.RGBLED(red, green, blue, active_high, initial_value, pwm)'''
** Main parameters:
** red: The GPIO pin that controls the red component of the RGB LED
** green: The GPIO pin that controls the green component of the RGB LED
** blue: The GPIO pin that controls the blue component of the RGB LED
** active_high:
*** Set to True (default) for common cathode RGB LEDs.
*** Set to False for common anode RGB LEDs.
** initial_value:
*** The initial color of the RGB LED. Default is black (0,0,0).
** pwm:
*** If True (default), constructs PWMLED instances for each component of the RGBLED.
*** If False, constructs regular LED instances. This prevents smooth color transitions.

*For more commands, please refer to the [https://gpiozero.readthedocs.io/en/latest/installing.html gpiozero documentation]

== Example Download ==
* [[:File:Basic Experiment Kits For Arduino.zip|Arduino Example Programs]]
* [[:File:Basic Experiment Kits For Raspberry Pi.zip|Raspberry Pi 5 Example Programs in Python]]

== Related Examples ==
{{Arduino and Raspberry Pi Case}}