#define RED 7
#define GRN 8
#define BLU 9

void setup() {
 pinMode(RED, OUTPUT);
 pinMode(GRN, OUTPUT);
 pinMode(BLU, OUTPUT);
}

void loop() {
 setColor(255, 0, 255);
 delay(1000);
 setColor(0, 255, 255);
 delay(1000);
 setColor(80, 100, 200);
 delay(1000);
 setColor(255, 255, 255);
 delay(1000);
}

void setColor(int R, int G, int B) {
 analogWrite(RED, R);
 analogWrite(GRN, G);
 analogWrite(BLU, B);
}