LearnigKit for DevTerm uno 2

//uno_4chrelaymodule

int ch1=2,ch2=3,ch3=4,ch4=5;

void setup()

{

  pinMode(ch1,OUTPUT);

  pinMode(ch2,OUTPUT);

  pinMode(ch3,OUTPUT);

  pinMode(ch4,OUTPUT);

}

void loop()

{

  digitalWrite(ch1,LOW);

  digitalWrite(ch2,LOW);

  digitalWrite(ch3,LOW);

  digitalWrite(ch4,LOW);

  delay(1000);

  

  digitalWrite(ch1,HIGH);

  digitalWrite(ch2,LOW);

  digitalWrite(ch3,LOW);

  digitalWrite(ch4,HIGH);

  delay(1000);

  

  digitalWrite(ch1,LOW);

  digitalWrite(ch2,HIGH);

  digitalWrite(ch3,HIGH);

  digitalWrite(ch4,LOW);

  delay(1000);

  

  digitalWrite(ch1,LOW);

  digitalWrite(ch2,HIGH);

  digitalWrite(ch3,LOW);

  digitalWrite(ch4,HIGH);

  delay(1000);

}