Next Page: Rationale

Creating a Monoprogram Dialog
with Turbo Pascal

Alastair Milne

ETC's dialogues have for the last several years been organised as sets of several separate modules, gathered under an overall program that offers the student a menu of the dialogues. Frequently some reasonably striking display derived from the dialogue's subject area is first presented repeatedly until a user arrives and asks for the menu. This has been called the ``attract mode''. In some dialogues these modules are also joined sequentially, as when they form a related series.

In this traditional format, the attract mode (containing a menu of all the modules), and each module, is a separate program. When the user chooses a module from the attract mode's menu, the attract causes the execution of the chosen program, terminating itself in the process.

In the new monoprogram format, all these components are united in one program whose main routine is the attract display followed by the menu.

The rationale for this new format, including a lengthy comparison of the DOS and p-System features that suggested it, is given later on.

• Rationale
• Converting Modules into Units
  • Units Belonging to Modules
• Converting Attract Mode into Main Program
  • Making and Using the Overlays
  • The Module-Calling Cycle
  • Cleaning up after Modules
  • State Machine
• Setup for Ports
  • Preparing for PtInit
  • Chaining with the units DlgGlbls and MarkJump