Understanding blinking LED commands

I'm new to Arduino and need help understanding the assembly commands in this program sketch for a blinking LED using Arduino UNO R3. For example, what command turns on and off the LED?
how the LED is set to an output?

lab1Capture.PNG

lab1Capture.PNG

Start here (pg. 280 or thereabouts)

rolas:
I'm new to Arduino and need help

Are you new to microcontrollers? Are you new to any type of coding? If so, I would opine that assembly language code is not the place to start learning.

HINTS: 0x04 is the address of the DDRB register. 0x05 is the address of the PORTB register. Bit 5 in those registers control Pin 13, a.k.a. LED_BUILTIN on the Arduino UNO.

This is what it appears to be doing:

void setup()
{
   pinMode(LED_BUILTIN, OUTPUT);  // Set bit 5 of DDRB to make Pin 13 an OUTPUT
}

void loop()
{
  while (true)
  {
     digitalWrite(LED_BUILTIN, HIGH);  // Set bit 5 of PORTB
     myDelay(40);
     digitalWrite(LED_BUILTIN, LOW);   // Clear bit 5 of PORTB
     myDelay(40);
  }
}

void myDelay(byte count)
{
  // Use 'volatile' to keep the loops from being optimized away
  volatile byte r8 = 0;
  volatile byte r9 = 0;
  while (--count)
    while (--r9)     // Loop 256 times:
      while (--r8);  // Loop 256 times
}