{***********************************************************************
*                                                                      *
*  alle Routinen fuer COM-Files mit Endadress < 8000h !                *
*                                                                      *
***********************************************************************}


var h_anf : integer absolute $8000;

procedure h_ein;

begin
inline ($F3);  (*DI*)
port[$37C]:=$2E
end;

procedure h_aus;
begin
port[$37C]:=0;
inline ($FB)   (*EI*)
end;

const rtext : array[0..15] of byte =
             ($61,$50,$52,$0F,$19,$06,$19,$19,
              $02,$0D,$0C,$0C,$00,$00,$00,$00);

procedure h_text;
var i: byte;
begin
port [$378] := 0;
for i := 0 to $0f do begin
 port [$374] := i;
 port [$375] := rtext[i];
end;
port [$378] := 8;
end;

const gtext : array[0..15] of byte =
             ($35,$2D,$2E,$07,$5B,$02,$57,$57,
              $02,$03,$00,$00,$00,$00,$00,$00);

procedure h_graph;
var i: byte;
begin
port[$378] := 0;
for i := 0 to $0f do begin
 port[$374] := i;
 port[$375] := gtext[i];
end;
port[$37F] := $FF;
port[$378] := $0A;
end;


procedure h_clrscr;

begin
    H_EIN;
    fillchar(h_anf,$8000,0);
    H_AUS;
end;


function zieladresse (x, y :integer) :integer;

begin
    zieladresse := $8000 + (y and 3) shl 13 + 90 * (y shr 2) + (x shr 3);
end;


procedure h_plot(x,y:integer);

type pointer = ^byte;
     feld8   = array [1..8] of byte;

const punkt : feld8
            = (128,64,32,16,8,4,2,1);

var  zeiger : pointer;
     offset : integer;
     bytewert : byte;

begin
    offset := zieladresse(x,y);
    bytewert := punkt [x and 7];
    zeiger := ptr(offset);
    zeiger^ := bytewert or zeiger^;
end;


procedure screen(i:integer);

begin
  write(#27,'z',chr(i))
end;


procedure fett;

begin
  write(#27,'p')
end;


procedure normal;

begin
  write(#27,'q')
end;


procedure clearall;

var i : integer;

begin
  for i := 0 to 6 do
  write(#27,'z',chr(i),12,#27,'q',#27,'Y  ')
end;