CONST, TYPE, VAR

     The following are globally declared in the FastTTT5 unit:

     CONST
          MAXSCREENSTR = 80;
          FCOL: BYTE   = WHITE;
          BCOL: BYTE   = BLACK;
     TYPE
          STRSCREEN: STRING[MAXSCREENSTR];
     VAR
          BASEOFSCREEN: WORD;
          VSEG: WORD;
          VOFS: WORD;
          SNOWPRONE: BOOLEAN;
          SPEED: LONGINT;

     Fcol, Bcol - these are variable constants, i.e. you can assign new
     values to them at any time in the program. They are the display colors
     used by the procedures ColWrite, FWrite and FWriteLn.

     StrScreen - this type is used throughout the Toolkit. Since the screen
     can only display 80 characters per line, most of the screen-related
     procedures and functions in the Toolkit expect strings up to 80
     characters long, i.e. strings of type StrScreen. To use other string
     types, set the string compiler directive off with {$V-}.

     BaseOfScreen - this word variable is automatically updated at program
     execution time. It holds the base address of video memory, i.e. $B800
     for color systems and $B000 for monochrome systems. Use the function
     ColorScreen in preference to checking this variable.

     VSeg - this word variable is used internally and indicates the segment
     address of the base of the active screen.

     VOfs - this word variable is used internally and indicates the offset
     address of the base of the active screen.

     SnowProne - this boolean variable is automatically updated at program
     execution time. It is set to true if the system appears to suffer from
     snow, i.e. IBM CGA cards!

     Speed - this longint variable is automatically set at program
     execution time to 200. The variable affects the rate of "growth" in
     the GrowFBox procedure. Increase the value to reduce the speed (ugh!).