Function Hex(num: integer): HexStr;
 Const h: String[16]='0123456789ABCDEF';
  Var i, j:    integer;
      str:     hexstr;
  begin
    Str:='0000'; j:=num;
    For i:=4 DownTo 1 do
      begin
        Str[i]:=h[succ(j and $F)]; j:=j shr 4;
      end;
    Hex:=Str;
  end; { Function Hex }

{ getw - get a word value from the input file }
Function GetW: integer;
  Var in1,in2: char;
  begin
    ReadInFile(In1); ReadInFile(In2);
    GetW:=ord(in1) + ord(in2) shl 8;
  end; { Function GetW }

Function GetI: integer;
  Var ch: Char;
  begin
    ReadInFile(ch); GetI:=ord(ch);
  end; { Function GetI }

Function GetUHuff: char;
  Var i: integer;
  begin
    i:=0;
    Repeat
      BPos:=succ(BPos);
      If BPos>7 then
        begin
          CurIn:=GetI; BPos:=0;
        end
      else CurIn:=CurIn shr 1;
      i:=ord(DNode[i,ord(CurIn and $0001)]);
    Until (i<0);
    i:=-(succ(i));
    If i=SpEOF then
      begin
        EoFile:=true; GetuHuff:=chr(26)
      end
    else GetUHuff:=chr(i);
  end; { Function GetUHuff }

Function GetCr: char;
  var C: char;
  begin
    If (RepCt>0) then
      begin RepCt:=pred(RepCt); GetCr:=LastChar; end
    else
      begin
        C:=GetuHuff;
        If C<>DLE then begin GetCr:=C; LastChar:=C; end
        else
          begin
            RepCt:=ord(GetuHuff);
            If RepCt=0 then GetCr:=DLE
            else begin RepCt:=pred(pred(RepCt)); GetCr:=LastChar; end;
          end;
      end;
  end; { Function GetCr }