{
    This file is part of the Free Pascal run time library.
    Copyright (c) 1999-2000 by the Free Pascal development team.

    Borland Pascal 7 Compatible CRT Unit - Interface section

    See the file COPYING.FPC, included in this distribution,
    for details about the copyright.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

 **********************************************************************}

Const
{ CRT modes }
  BW40          = 0;            { 40x25 B/W on Color Adapter }
  CO40          = 1;            { 40x25 Color on Color Adapter }
  BW80          = 2;            { 80x25 B/W on Color Adapter }
  CO80          = 3;            { 80x25 Color on Color Adapter }
  Mono          = 7;            { 80x25 on Monochrome Adapter }
  Font8x8       = 256;          { Add-in for ROM font }

{ Mode constants for 3.0 compatibility }
  C40           = CO40;
  C80           = CO80;

{ Foreground and background color constants }
  Black         = 0;
  Blue          = 1;
  Green         = 2;
  Cyan          = 3;
  Red           = 4;
  Magenta       = 5;
  Brown         = 6;
  LightGray     = 7;

{ Foreground color constants }
  DarkGray      = 8;
  LightBlue     = 9;
  LightGreen    = 10;
  LightCyan     = 11;
  LightRed      = 12;
  LightMagenta  = 13;
  Yellow        = 14;
  White         = 15;

{ Add-in for blinking }
  Blink         = 128;

var

{ Interface variables }
  CheckBreak: Boolean;    { Enable Ctrl-Break }
  CheckEOF: Boolean;      { Enable Ctrl-Z }
  DirectVideo: Boolean;   { Enable direct video addressing }
  CheckSnow: Boolean;     { Enable snow filtering }
  LastMode: Word = 3;         { Current text mode }
  TextAttr: Byte = $07;         { Current text attribute }
  WindMin: Word  = $0;          { Window upper left coordinates }
  WindMax: Word  = $184f;          { Window lower right coordinates }
  { FPC Specific for large screen support }
  WindMinX : DWord;
  WindMaxX : DWord;
  WindMinY : DWord;
  WindMaxY : DWord      ;

type
  { all crt unit coordinates are 1-based }
  tcrtcoord = 1..255;

{ Interface procedures }
procedure AssignCrt(var F: Text);
function KeyPressed: Boolean;
function ReadKey: Char;
procedure TextMode (Mode: word);
{ Window parameters not changed to tcrtcoord, because the window() procedure
  does nothing if (x1 > x2) or (y1 > y2), and some people may set x2 or y2
  to 0 if they don't want it to do anything (JM)
}
procedure Window(X1,Y1,X2,Y2: Byte);
procedure GotoXY(X,Y: tcrtcoord);
function WhereX: tcrtcoord;
function WhereY: tcrtcoord;
procedure ClrScr;
procedure ClrEol;
procedure InsLine;
procedure DelLine;
procedure TextColor(Color: Byte);
procedure TextBackground(Color: Byte);
procedure LowVideo;
procedure HighVideo;
procedure NormVideo;
procedure Delay(MS: Word);
procedure Sound(Hz: Word);
procedure NoSound;

{Extra Functions}
procedure cursoron;
procedure cursoroff;
procedure cursorbig;