CHAPTER 1 - Introduction

GRAFIX is a memory resident graphics and sound program for your Tandy 1000/PCjr series personal computer. It provides you with a complete set of graphics and sound functions that can be executed from your favorite programming language such as compiled BASIC and PASCAL. To use GRAFIX just install it when you start up your computer by including the following lines in your AUTOEXEC.BAT file:

  TANDY11
  GRAFIX

That's all there is to it. Since the program is memory resident you can use any of the program's sound and graphic functions anytime you want. The TANDY11 program is necessary if own a Tandy 1000 SL/TL/RL computer. This enables those computers to do 640x200x16 color graphics. (See chapter 4 for more information on the TANDY11 program)

The following list are some of the functions GRAFIX provides you with:

• Points
• Lines
• Circles and ellipses
• Line and solid boxes
• Filling irregular areas with color
• Storing and transferring areas of the graphic screen
• Variable screen viewport
• Multiple video pages
• Printing text strings on the graphics screen
• Graphics text cursor
• Using the Tandy 1000/PCjr's 3 voice sound and noise capabilities
• Making sounds and noises in background while your program executes
• Changing the speed of the system timer for precise sound and noise duration
• Three different graphic modes supported:
  • 160x200x16 color graphics
  • 320x200x16 color graphics
  • 640x200x16 color graphics (Tandy 1000 SL/TL/RL only)

These functions are accessed by passing the GRAFIX program a set values through your computer's CPU registers and executing an INT instruction. Sounds pretty easy, huh! Well, you never have to be that concerned with the mechanics of the GRAFIX program. I have provided you with a set of interfacing programs for compiled BASIC and PASCAL. These interfaces act as a translator between your program and the GRAFIX program. For example, if you wanted to draw a blue box in Turbo PASCAL all you have to do is include a line like this in your program:

  DrawBox(0, 0, 319, 199, 1);

The interface takes the values passed to it, places the values into the CPU registers, and executes the INT instruction without you ever having to worry about those intricate details. The following is list of interfaces for programming languages currently provided:

• Microsoft QuickBASIC 4.0 and greater
• Borland Turbo BASIC 1.0 - 1.1
• SPECTRA Publishing PowerBASIC 2.0 - 2.1
• Microsoft QuickPASCAL 1.0 and greater
• Borland Turbo PASCAL 4.0 and greater

Chapter 2 describes the BASIC and PASCAL programming interfaces telling you what each function does and how to use it in your program. For those of you who have a different programming language and would like to design your own interface, read chapter 3. This describes the ASSEMBLY language interface for GRAFIX. It gives all the technical information necessary for setting up an interface for any other programming language such as C. Chapter 4 discusses the two utility programs, ADJMEM and TANDY11 provided with the GRAFIX package. Chapter 5 gives all the miscellaneous details of GRAFIX.