(*

Question:
How do I write a raw string of a data to the printer?

The following unit "PrtRaw.pas" demonstrates a 16/32 bit
raw printing unit for Delphi and Borland C Builder.

Following the unit, is an exmaple on using the
PrtRaw unit.

Notes:

1) You are responsible for embedding all necessary
control codes that the printer may require (including
form feed codes).

2) You must specify a valid printer and port name.

*)

unit PrtRaw;

{Copyright (c) 1998 by Joe C. Hecht - All rights Reserved}
{joehe...@gte.net You may use and share this unit}
{providing my name and the copyright notice stays intact.}

interface

uses
  WinTypes;

{$IFDEF WIN32}
 type SpoolInt = DWORD;
{$ELSE}
 type SpoolInt = integer;
{$ENDIF}

function StartRawPrintJob(PrinterName : pChar;
                          Port : pChar;
                          DocName : pChar) : THandle;

function StartRawPrintPage(hPrn : THandle) : integer;

function PrintRawData(hPrn : THandle;
                      Buffer : pointer;
                      NumBytes : SpoolInt) : integer;

function EndRawPrintPage(hPrn : THandle) : integer;

function EndRawPrintJob(hPrn : THandle) : integer;

implementation
 uses
   WinProcs,
{$IFDEF WIN32}
 WinSpool;
{$ELSE}
 Print;
{$ENDIF}

function StartRawPrintJob(PrinterName : pChar;
                          Port : pChar;
                          DocName : pChar) : THandle;
{$IFDEF WIN32}
 var
   hPrn : THandle;
   DocInfo1 : TDocInfo1;
{$ENDIF}
begin
 {$IFDEF WIN32}
   if (OpenPrinter(PChar(PrinterName),
                   hPrn,
                   nil) = FALSE)  then begin
     Result := THandle(-1);
     Exit;
   end;
   DocInfo1.pDocName := DocName;
   DocInfo1.pOutputFile := Port;
   DocInfo1.pDataType := 'RAW';
   if (StartDocPrinter(hPrn,
                       1,
                       @DocInfo1) = 0) then begin
     Result := THandle(-1);
     exit;
   end;
   Result := hPrn;
 {$ELSE}
  result := OpenJob(Port,
                    DocName,
                    0);
 {$ENDIF}
end;

function StartRawPrintPage(hPrn : THandle) : integer;
begin
 {$IFDEF WIN32}
   if (StartPagePrinter(hPrn) = FALSE) then begin
     Result := -1;
     exit;
   end;
   result := 1;
 {$ELSE}
  result := StartSpoolPage(hPrn);
 {$ENDIF}
end;

function PrintRawData(hPrn : THandle;
                      Buffer : pointer;
                      NumBytes : SpoolInt) : integer;
{$IFDEF WIN32}
var
  BytesWritten : DWORD;
 {$ENDIF}
begin
  if (NumBytes = 0) then begin
    Result := 1;
    exit;
  end;
 {$IFDEF WIN32}
   if (WritePrinter(hPrn,
                    Buffer,
                    NumBytes,
                    BytesWritten) = FALSE) then begin
     Result := -1;
     exit;
   end;
   if (NumBytes <> BytesWritten) then begin
     Result := -1;
     exit;
   end;
   Result := 1;
 {$ELSE}
  result := WriteSpool(hPrn,
                       Buffer,
                       NumBytes);
 {$ENDIF}
end;

function EndRawPrintPage(hPrn : THandle) : integer;
begin
 {$IFDEF WIN32}
   if (EndPagePrinter(hPrn) = FALSE) then begin
     Result := -1;
     exit;
   end;
   Result := 1;
 {$ELSE}
  result := EndSpoolPage(hPrn);
 {$ENDIF}
end;

function EndRawPrintJob(hPrn : THandle) : integer;
begin
 {$IFDEF WIN32}
   if (EndDocPrinter(hPrn) = FALSE) then begin
     Result := -1;
     exit;
   end;
   if (ClosePrinter(hPrn) = FALSE) then begin
     Result := -1;
     exit;
   end;
   Result := 1;
 {$ELSE}
  result := CloseJob(hPrn);
 {$ENDIF}
end;

end.

(*

Example of use:

uses
  PrtRaw;

procedure TForm1.Button1Click(Sender: TObject);
var
  hPrn : THandle;
  Data : array[0..31] of char;
begin

  hPrn := StartRawPrintJob('Generic / Text Only',
                           'LPT1:',
                           'My Document');
  if (integer(hPrn) < 0) then begin
    ShowMessage('StartRawPrintJob Failed');
    exit;
  end;

  if (StartRawPrintPage(hPrn) < 0) then begin
    ShowMessage('StartRawPrintPage Failed');
    EndRawPrintJob(hPrn);
    exit;
  end;

  Data[0] := 'P';
  Data[1] := 'a';
  Data[2] := 'g';
  Data[3] := 'e';
  Data[4] := #32;
  Data[5] := '1';
  Data[6] := #13;
  Data[7] := #10;

  if (PrintRawData(hPrn,
                   @data,
                   8) < 0) then begin
    ShowMessage('PrintRawData Failed');
    EndRawPrintPage(hPrn);
    EndRawPrintJob(hPrn);
    exit;
  end;

  if (EndRawPrintPage(hPrn) < 0) then begin
    ShowMessage('EndRawPrintPage Failed');
    EndRawPrintJob(hPrn);
    exit;
  end;

  if (StartRawPrintPage(hPrn) < 0) then begin
    ShowMessage('StartRawPrintPage Failed');
    EndRawPrintJob(hPrn);
    exit;
  end;
  Data[0] := 'P';
  Data[1] := 'a';
  Data[2] := 'g';
  Data[3] := 'e';
  Data[4] := #32;
  Data[5] := '2';
  Data[6] := #13;
  Data[7] := #10;

  if (PrintRawData(hPrn,
                   @data,
                   8) < 0) then begin
    ShowMessage('PrintRawData Failed');
    EndRawPrintPage(hPrn);
    EndRawPrintJob(hPrn);
    exit;
  end;

  if (EndRawPrintPage(hPrn) < 0) then begin
    ShowMessage('EndRawPrintPage Failed');
    EndRawPrintJob(hPrn);
    exit;
  end;

  if (EndRawPrintJob(hPrn) < 0) then begin
    ShowMessage('EndRawPrintJob Failed');
    exit;
  end;

end;

end.

uses printer;

...

writeln( lst, 'test');

is the simpliest way.  If you want to use effects then you send
a code that depends on the printer (but most follow the Epson
standards).