We are going to be making the infamous hello world program. This is far more difficult in Assembly Language than it is in most other languages.
This tutorial will cover simple output and how to declare Constants. The program's main purpose, however, is to teach you how to use EASy68K.


  


    When you open the EASy68K editor/assembler (EDIT68K.exe) you will see a screen similar to this:
  


    We will start by making comments for what this program does.

Now we will begin coding.

  


    The LEA command stands for Load Effective Address, which in this case it loads the address of the item labeled MESSAGE into address register A1
    MOVE.B stands for Move Byte (could also be MOVE.W for word or MOVE.L for long), #14 means the literal number 14 (if we just used 14 it would be memory location 14). D0 is a data register. Once this instruction has been ran D0 will contain the number 14.
    TRAP #15 does a Simulator input or output command based on the contents of D0 hereafter these will be referred to as trap tasks for example:
      MOVE.B	#14,D0
      TRAP #15 Is trap task 14

      MOVE.B #4,D0
      TRAP #15 Is trap task 4
    Here is a list of various trap tasks and what they do.
    For a list of trap tasks to use for purposes other than Text I/O consult the EASy68K help section.
    MESSAGE is a label DC.B reserves memory for the item following it (in this case our message) because trap task 14 requires a NULL to terminate the string we must follow our message with 0.
  


    Now we will assemble and run our program, first click the assemble button, which looks like this.
  


    Assuming you entered everything correctly you should see this
    If you get an error make sure you entered everything correctly, or you can get the completed file from here.
  


    Once the program is assembled without error click the execute button, which will open the EASy68K simulator shown at the left.
  


    Next to start the program you will press the run button, which resembles the assemble button
  


    After the program runs you should see this
    If the ouput window did not open click View then Output Window. If it still does not work check the code again.

Now we will add code to allow display of a new line.

  


    Here is an example of the previous program with the carriage return and line feed added.
    CR and LF are as labels to use in place of the ASCII codes for the carriage return and line feed.

  

    This is how you would add a second line to your message. The terminating 0 was moved to the last line.
  

    Output of the code from above. Notice the text from the second DC.B is on the next line.
  

    The fourth line of MESSAGE shows how you can code multiple lines of text in a single DC.B.
  

    Output of the code from above. Notice the fourth DC.B's text is displayed on two lines. If your code does not work, you can recieve the correct code here
This concludes Part 1 of the tutorial. You should now be able to use EASy68K to write, assemble, and run a simple program.