program BootMkr;
(*****************************************************************
 This program loads the specified binary file onto the boot sector
 of the diskette placed in drive 'A'.
 *****************************************************************)
USES
  crt,
  dos;
CONST
  DiskInt     = $13;      { Diskette Interrupt }
  DiskReset   = 0;        { Reset the Drive Subsystem }
  DiskStatus  = 1;        { Get Status of Previous Operation }
  DiskRead    = 2;        { Read the Sectors in Memory }
  DiskWrite   = 3;        { Write to the Disk Sector }
VAR
  Regs        : registers;
  ByteBuffer  : array [0..511] of byte;  { 512-byte Data Buffer }
  Curr_byte   : byte;
  i,j         : integer;
  handle      : integer;  { File Handling Variable }
  handle_size : longint;  { File Handling Variable }
  SourceFile  : file of byte;  { File to Load into the Diskette }
BEGIN
  writeln;
  writeln('BOOTMKR 1.0B, (c) Jens Laland 2001');
  { Check Command Line Parameter }
  if ParamCount <> 1 then begin
    writeln;
    writeln('   USAGE:    BOOTMKR filename.ext');
    writeln;
    writeln('   This program loads the specified binary file');
    writeln('   onto the boot sector of diskette in drive A.');
    halt; end
  else begin
    Assign(SourceFile, ParamStr(1));
    {$I-}
    Reset(SourceFile);
    {$I+}
    { If file does not exist, or file not found... }
    if IOresult <> 0 then begin
      writeln(ParamStr(1), ' not found...');
      Halt;
    end;
    { Ensure that the file is within 512 bytes }
    if FileSize(SourceFile) > 512 then begin
      writeln('File too large to process [',FileSize(SourceFile),' bytes]');
      writeln('File cannot be larger than one 512-byte sector...');
      Halt; end
    else begin { Put the file on the Diskette }
      writeln('Processing ',ParamStr(1),' ',FileSize(SourceFile),' bytes...');
      for i := 1 to FileSize(SourceFile) do begin
        seek(SourceFile,i - 1);
        read(SourceFile,Curr_byte);
        ByteBuffer[i - 1] := Curr_byte;
      end;
      { Fill rest of 512-byte sector with NOP }
      for i := FileSize(SourceFile) to 512 do ByteBuffer[i - 1] := $90;
      { Reset Disk Drive A }
      Regs.AH := DiskReset;
      Regs.DL := 0;
      intr(DiskInt,Regs);
      if NOT(Regs.AH = 0) then begin
        writeln('Error writing to Drive A...');
        Halt; end
      else begin  { Write File onto Boot Sector }
        Regs.AH := DiskWrite;  { Write the First Sector }
        Regs.DL := 0;          { of Disk A }
        Regs.DH := 0;          { Head 0 }
        Regs.CH := 0;          { Track 0 }
        Regs.CL := 1;          { Sector 1 }
        Regs.AL := 1;          { ONLY 1 Sector }
        Regs.BX := Ofs(ByteBuffer[0]); { Buffer Offset }
        Regs.ES := Seg(ByteBuffer[0]); { Buffer Segment }
        Intr(DiskInt,Regs);
        if NOT(Regs.AH = 0) then
          writeln('Error writing to Drive A...');
      end;
    end;
  end;
END.