Now a days, a programmer of any language has to include user friendly features in his commercial software, since users desire user friendliness for easy use. For example, Windows is the most popular OS due to its Graphical User Interface.

I don't want to start a compiler-war in the assembler programmer's journal, but I do want to show some nice in-line assembly routines for FST Modula-2. FST (or Fitted Software Tools) was a shareware Modula-2 compile made by Roger Carvalho. He eventualy gave up the concept of shareware and made his final version freeware. If you look carefully you can find this package in many software repositories like Simtel. Also the FreeDOS website used to harbor this final version.

The reason behind this essay is to show how techniques first developed by virus writers can be used for benevolent purposes. It is my opinion that all knowledge is good and viral techniques are certainly no exception. I will lead you through the development of a program called DOSGUARD which benignly modifies DOS executables, both COM and EXE.

As a follow-up to the Direct Draw article in APJ#5, here are two complete DirectDraw sample programs. The first uses an 8-bit palette, while the second uses a 32-bit (truecolor) palette. To compile these, you will need to obtain Ddraw.inc ( {http://asmjournal.freeservers.com/files/Ddraw.inc.html} ) for the necessary DirectDraw definitions.

To assemble this program you are going to require most of the library routines I have so far presented here. You can consider this an example in just how easy it is to write software in assembler if you continue to build and refine a library system. The program probably took me about half an hour of work and most of that was making myself satisfied with the niceness of the code:-

Write a program that takes a snapshot of a text screen and writes it to a file. It should work in any text mode and lines should be terminated with newlines in the file so that it can easily be viewed in a standard editor. ( 04Dh = 77 bytes )

Here are some simple but very powerful library routines, primarily concerned with screen output. They all follow the same conventions:

• Routines preserve all registers that they are not specified to return.
• The direction flag (DF) should always be clear before calling.

All code is presented in MASM format. I do not use very many of the functions of this assembler so it should be trivial to assemble these under a different one. I do, however, use OPTION SCOPED, this means ...
Read More >>

ASSEMBLING ON ALPHA PART I

In this first article I will discover how to use functions written in alpha assembler in a program written in C. The example I give is a rather simple one. There are many things to know about alpha. This text shows that it is quite simple to use assembler on alpha.