Author:
Dr W.Buchanan,
Napier University,
Edinburgh.

Downloads:
Complete code
Port statement
Using Writeln/readln

Reviews:
Review

Introduction to Pascal and Delphi.
This book provides an introduction to programming with Pascal and extends this to show how Borland Delphi, which uses Pascal, is used to develop Microsoft Windows programs.

Why use Pascal/Delphi?
After many years of teaching software development to undergraduates I have found that C and C++ suffer from several pitfalls, especially in parame-ter passing, pointers and the lack of strong data type checking. These areas may provide flexibility for experienced programmers, but for novices they add to the complexity of the program. I have also been involved with extensive consultancy work and book writ-ing over the years and I have used C, C++ (Borland C++ and Visual C++), HTML/JavaScript, Java, Visual Basic, Turbo Pascal and Borland Delphi. From this, I can say, without doubt, that Delphi is the easiest and most power-ful development system I have found. It provides a great deal of flexibility in that it doesn't try to write all the code for the programmer, and basically it provides a framework for the user to add code to

Real-life Applications.
The best way to learn a programming language is to write real applications. For this reason the book includes many real-life applications. Chapters 13 to 20 cover some practical applications, such as: software interrupts, hardware interrupts, graphics, date and time, system commands, RS-232 and parallel ports. The book thus covers three main areas:

Pascal programming (Chapters 1 to 12).
Pascal applications (Chapters 13 to 20).
Delphi programming (Chapters 21 to 26).

Replacing PORT statements

The PORT command has disappeared from Delphi 3. This a real shame, but here is code which does the equivalent. The two routines are ReadPort() and WritePort().

unit DPort;
interface

function  ReadPort(port:word):byte;
procedure WritePort(data:byte; Port:word);

implementation
function ReadPort(port:word):byte;
 begin
   asm
     mov  dx, port
     cli
     in   al, dx  {read}
     out  dx, al  {..rewrite since some ports reset on 'reads'}
     sti
     mov  Result,al
   end;
 end;

 procedure WritePort(data:byte; Port:word);
 begin
   asm
     mov  dx, port
     cli
     mov  al, data
     out  dx, al       {..write}
     sti
   end;
 end;
end.

Dport.PAS

Dport.DCU

Replacement for WinCrt