Arduino UNO error

Question

I got a problem with this code from Arduino Projects Book, a very simple code soryy if is very obvius.

This is the code I wrote:

const int greenLEDpin = 9;
const int redLEDpin = 10;
const int blueLEDpin = 11;

const int redSensorpin = A0;
const int greenSensorpin = A1;
const int blueSensorpin = A2;

int redValue = 0;
int greenValue = 0;
int blueValue = 0;

void setup() {
  Serial.begin(9600);

  pinMode(greenLEDpin,OUTPUT);
  pinMode(redLEDpin,OUTPUT);
  pinMode(blueLEDpin,OUTPUT);

}

void loop() {

  redSensorValue = analogRead(redSensorpin);
  delay (5);
  greenSensorValue = analogRead(greenSensorpin);
  delay(5);
  blueSensorValue = analogRead(blueSensorpin);

  Serial.print("Raw Sensor Values \t Red: ");
  Serial.print(redSensorValue);
  Serial.print("\t Green: ");
  Serial.print(greenSensorValue);
  Serial.print("\t Blue: ");
  Serial.println(blueSensorValue);

  redValue = redSensorValue/4;
  greenValue = greenSensorValue/4;
  blueValue = blueSensorValue/4;

  Serial.print("Mapped Sensor Values \t ReD: ");
  Serial.print(redValue);
  Serial.print("\t Green: ");
  Serial.print(greenValue);
  Serial.print("\t Blue: ");
  Serial.print(blueValue);
  analogWrite(redLEDpin, redValue);
  analogWrite(greenLEDpin, greenValue);
  analogWrite(blueLEDpin, blueValue);
}

And here is the error: Arduino:1.7.10 (Windows 8.1), Placa:"Arduino Uno"

LED_tricolor.ino: In function 'void loop()':

LED_tricolor.ino:24:2: error: 'redSensorValue' was not declared in this scope

LED_tricolor.ino:26:2: error: 'greenSensorValue' was not declared in this scope

LED_tricolor.ino:28:2: error: 'blueSensorValue' was not declared in this scope

Someone knows whats happening here? I tried some things like puting the variables before, but nothing... Hope u guys can help me ^^.

Answer 1

Try to add this just before the setup:

int redSensorValue = 0; 
int greenSensorValue = 0; 
int blueSensorValue = 0; 

Or if you prefer, you can just add int before the name of your variables in the loop.

Answer 2

You did not add any sensor pin in setup() function. Edit you function just like it.

void setup() {

  pinMode(redSensorpin,INPUT);
  pinMode(greenSensorpin,INPUT);
  pinMode(blueSensorpin,INPUT);

  pinMode(greenLEDpin,OUTPUT);
  pinMode(redLEDpin,OUTPUT);
  pinMode(blueLEDpin,OUTPUT);
  Serial.begin(9600);

}