Using an Assembler:

If you are utilizing a DOS based assembler, you shall need to get to DOS. The initial step in writing a program is to define the problem as completely as possible. You shall always think of things as you go along that you left out. After thinking out the problem, you begin by typing up a source file. Source files all end with the .asm extension. The extensions formed by the assembler are .obj, which is the object file, and .lst, which is the listing file. The listing file illustrates all the addresses resolved by the assembler, all of the code produced and all the comments. This file is extremely important in for assisting you in the laboratory. The listing file also shows any errors in the assembly procedure so that you may correct them. It is critical that you look at the listing file to be sure that there are no errors listed. The way you would use a program in real life is to write each program, assemble it, and then execute it.