The program is not very big, but still wants to standardize, write the main function and the child function, and put it in a different file so that you need to use the knowledge of the library file. On the textbook before, because the authors use a pseudo-instruction .Startup, the self-container saves the DS register, so there is no mention of the problem to save the register on the book. My own procedure is not used .Startup pseudo directive, and does not manually save the DS register, so it will be wrong.
