/* comment with multiple lines

> Battle of the bytes

> 23rd May 2025 

> ISS Archimede

> comment with multiple lines

*/





/*

The following CODE is an example of binary counter with 1 digit (LED0):

LED1 LED0 

 0     0   delay 1000mS

 0     1   delay 1000mS





-> we kindly ask you to write a code that generates a binary COUNTDOWN  with 2 digits:

LED1 LED0 

  1     1   delay 1000mS

  1     0   delay 1000mS

  0     1   delay 1000mS

  0     0   delay 1000mS



  1     1   delay 300mS

  1     0   delay 300mS

  0     1   delay 300mS

  0     0   delay 300mS



  1     1   delay 300mS    blink LED1 & LED2 4 times

  0     0   delay 300mS

  1     1   delay 300mS

  0     0   delay 300mS

  1     1   delay 300mS

  0     0   delay 300mS

  1     1   delay 300mS

  0     0   delay 300mS







and so on ...

you can check the CODE thanks to Arduino circuit

*/



// this line is comment

// constants won't change. Used here to set a pin number:

const int led0Pin = 2;  //  declares led0Pin integer and assign led0Pin = 2 (-> pin 2) - LSB, least significant bit -> LED0

const int led1Pin = 4;  //  declares led0Pin integer and assign led1Pin = 4 (-> pin 4) - MSB, most significant bit  -> LED1





void setup() 

{

// -> TO RUN ONCE, setup code <- define pin 2 and pin 4 as OUTPUT:

  pinMode(led0Pin, OUTPUT);   // I/O PIN n.2 defined as OUTPUT

  pinMode(led1Pin, OUTPUT);   // I/O PIN n.4 defined as OUTPUT

}





void loop()

{

// put your main code here, to run repeatedly:



  digitalWrite(led0Pin, HIGH);  // turn ON led0

  delay(1000);               //delay 1000mS or 1 sec.

  digitalWrite(led0Pin, LOW);   // turn OFF led0

  delay(1000);

    

}