User Manual

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Code
After wiring, please open the program in the code folder- Lesson 4 RGB LED, and
click UPLOAD to upload the program. See Lesson 2 for details about program
uploading if there are any errors.
Our code will use FOR loops to cycle through the colors.
The first FOR loop will go from RED to GREEN.
The second FOR loop will go from GREEN to BLUE.
The last FOR loop will go from BLUE to RED.
Try the sketch out and then we will dissect it in some detail......
The sketch starts by specifying which pins are going to be used for each of the colors:
// Define Pins
#define BLUE 3
#define GREEN 5
#define RED 6
The next step is to write the 'setup' function. As we have learnt in earlier lessons,
the setup function runs just once after the Arduino has reset. In this case, all it has
to do is define the three pins we are using as being outputs.
void setup()
{
pinMode(RED, OUTPUT);
pinMode(GREEN, OUTPUT);
pinMode(BLUE, OUTPUT);
digitalWrite(RED, HIGH);
digitalWrite(GREEN, LOW);
digitalWrite(BLUE, LOW);
}
Before we take a look at the 'loop' function, let’s look at the last function in the
sketch.
The define variables
redValue = 255; // choose a value between 1 and 255 to change the color.
greenValue = 0;