Can't get lights to work in a relay

Using Arduino LEDs and Multiplexing
1

Hi. I hope this is the correct forum to ask about this kind of issues. I' ve been trying to set a relay to activate lights with arduino, but i can't make the lights turn on after sending a value. The relay is set so lights go on in the LOW position, and i already tested the circuit with this code

void setup()
{
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  digitalWrite(4, HIGH);
    digitalWrite(5, HIGH);
      digitalWrite(2, HIGH);
        digitalWrite(3, HIGH);
  Serial.begin(9600);
}

void loop()
{
  digitalWrite(4, LOW);
  delay(1000);
  digitalWrite(4, HIGH);
  delay(1000);
  digitalWrite(5, LOW);
  delay(1000);
  digitalWrite(5, HIGH);
  delay(1000);
  digitalWrite(2, LOW);
  delay(1000);
  digitalWrite(2, HIGH);
  delay(1000);
  digitalWrite(3, LOW);
  delay(1000);
  digitalWrite(3, HIGH);
  delay(1000);
     */  
}
        
}

and everything worked out just fine, so i know i didn't make a bad installation.

Now, i tried to make a code based on different values of a variable called "senal" as conditions to turn on or off the lights. The only problem is that when i send the value, nothing happens.

Here is that code.

int senal;

void setup()
{
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  digitalWrite(4, HIGH);
  digitalWrite(5, HIGH);
  digitalWrite(2, HIGH);
  digitalWrite(3, HIGH);
  Serial.begin(9600);
}

void loop()
{
  if (Serial.available()>0)
  {senal = Serial.read();
    if (senal  == 1) 
     {digitalWrite(2, LOW);
      digitalWrite(3, HIGH);      
      digitalWrite(4, HIGH);      
      digitalWrite(5, HIGH);}}
    else if (senal  == 2) 
     {digitalWrite(3, LOW);
      digitalWrite(4, HIGH);
      digitalWrite(5, HIGH);
      digitalWrite(2, HIGH);}
    else if (senal == 3) 
     {digitalWrite(4, LOW);
      digitalWrite(5, HIGH);
      digitalWrite(2, HIGH);
      digitalWrite(3, HIGH);}
    else if (senal  == 4) 
     {digitalWrite(5, LOW);
      digitalWrite(2, HIGH);
      digitalWrite(3, HIGH);
      digitalWrite(4, HIGH);}



}

Any help with this is gratly appreciated. Oh, and sorry if my english is not that clear.

2

I think it's because it's actually sending you a character not an integer.

So try declare senal as a char and put the 1, 2 etc in single quotes '1', '2' etc.

edit.... for example I found this in some old code of mine:

char incomingByte;

followed then by....

void loop() 
{
   if (Serial.available() > 0) {
                // read the incoming byte:
                incomingByte = Serial.read();

                // say what you got:
                Serial.print("I received: ");
                Serial.println(incomingByte);
        }
        
        
        
         if (incomingByte == '8')
        {
          Serial.println("forward");
          goForward();
        }
        else if (incomingByte == '2')
        {
          Serial.println("backward");
          goBackward();
        }
3

Thanks a lot! That was definitely it.