Why call function A_GetUSBBufferLen() from winppla.dll doesn't work on Delphi Tokyo?

Question

I'm trying to work with Argox printer OS-214 Plus in Windows 10. I've connected the printer and Windows 10 recognized it but I haven't installed any driver.

I've downloaded Command-Library-V409 and extracted Delphi 2009 example from path ..\Command Library V409\PPLA\Example\Win32\Delphi_2009. There is a folder called release with a compiled exe called Delphi_2009.exe. I put in release the dll's WinPort.dll and Winppla.dll extracted from ..\Command Library V409\PPLA\Library\32-bit. Finally, I run Delphi_2009.exe and it worked as expected, showing the message bellow before print:

So I've tried to run the example bellow in Delphi Tokyo:

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

    var dpCrLf : AnsiString = chr(13)+chr(10);
    var szSavePath : String = 'C:\Argox';
    var szSaveFile : AnsiString = 'C:\Argox\PPLA_Example.Prn';
    var sznop1     : AnsiString = 'nop_front' + Chr(13) + chr(10);
    var sznop2     : AnsiString = 'nop_middle' + Chr(13) + chr(10);
    function  A_Bar2d_Maxi(x:integer; y:integer; primary:integer; secondary:integer; country:integer;
              service:integer; mode:char; numeric:integer; data:AnsiString):integer;stdcall;
              external 'WINPPLA.DLL';
    function  A_Bar2d_Maxi_Ori(x:integer; y:integer; ori:integer; primary:integer; secondary:integer;
              country:integer; service:integer; mode:char; numeric:integer; data:AnsiString):integer;
              stdcall;external 'WINPPLA.DLL';
    function  A_Bar2d_PDF417(x:integer; y:integer; narrow:integer; width:integer; normal:char;
              security:integer; aspect:integer; row:integer; column:integer; mode:char;
              numeric:integer; data:AnsiString):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Bar2d_PDF417_Ori(x:integer; y:integer; ori:integer; narrow:integer; width:integer;
              normal:char; security:integer; aspect:integer; row:integer; column:integer; mode:char;
              numeric:integer; data:AnsiString):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Bar2d_DataMatrix(x:integer; y:integer; rotation:integer; hor_mul:integer;
              ver_mul:integer; ECC:integer; data_format:integer; num_rows:integer; num_col:integer;
              mode:char; numeric:integer; data:AnsiString):integer;stdcall;external 'WINPPLA.DLL';
    Procedure A_Clear_Memory();stdcall;external 'WINPPLA.DLL';
    Procedure A_ClosePrn();stdcall;external 'WINPPLA.DLL';
    function  A_CreatePrn(selection:integer; filename:AnsiString):integer;stdcall;
              external 'WINPPLA.DLL';
    function  A_Del_Graphic(mem_mode:integer; graphic:AnsiString):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Draw_Box(mode:char; x:integer; y:integer; width:integer; height:integer; top:integer;
              side:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Draw_Line(mode:char; x:integer; y:integer; width:integer; height:integer):integer;
              stdcall;external 'WINPPLA.DLL';
    Procedure A_Feed_Label();stdcall;external 'WINPPLA.DLL';
    function  A_Get_DLL_Version(nShowMessage:integer):PAnsiChar;stdcall;external 'WINPPLA.DLL';
    function  A_Get_DLL_VersionA(nShowMessage:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Get_Graphic(x:integer; y:integer; mem_mode:integer; format:char; filename:AnsiString):integer;
              stdcall;external 'WINPPLA.DLL';
    function  A_Get_Graphic_ColorBMP(x:integer; y:integer; mem_mode:integer; format:char;
              filename:AnsiString):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Get_Graphic_ColorBMPEx(x:integer; y:integer; nWidth:integer; nHeight:integer;
              rotate:integer; mem_mode:integer; format:char; id_name:AnsiString; filename:AnsiString):integer;
              stdcall;external 'WINPPLA.DLL';
    function  A_Get_Graphic_ColorBMP_HBitmap(x:integer; y:integer; nWidth:integer; nHeight:integer;
              rotate:integer; mem_mode:integer; format:char; id_name:AnsiString; hbm:HBITMAP):integer;
              stdcall;external 'WINPPLA.DLL';
    function  A_Initial_Setting(Type_Renamed:integer; Source:AnsiString):integer;stdcall;
              external 'WINPPLA.DLL';
    function  A_WriteData(IsImmediate:integer; pbuf:AnsiString; length:integer):integer;stdcall;
              external 'WINPPLA.DLL';
    function  A_ReadData(pbuf:PAnsiChar; length:integer; dwTimeoutms:integer):integer;stdcall;
              external 'WINPPLA.DLL';
    function  A_Load_Graphic(x:integer; y:integer; graphic_name:AnsiString):integer;stdcall;
              external 'WINPPLA.DLL';
    function  A_Open_ChineseFont(path:AnsiString):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Print_Form(width:integer; height:integer; copies:integer; amount:integer;
              form_name:AnsiString):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Print_Out(width:integer; height:integer; copies:integer; amount:integer):integer;
              stdcall;external 'WINPPLA.DLL';
    function  A_Prn_Barcode(x:integer; y:integer; ori:integer; type_Renamed:char; narrow:integer;
              width:integer; height:integer; mode:char; numeric:integer; data:AnsiString):integer;
              stdcall;external 'WINPPLA.DLL';
    function  A_Prn_Text(x:integer; y:integer; ori:integer; font:integer; type_Renamed:integer;
              hor_factor:integer; ver_factor:integer; mode:char; numeric:integer; data:AnsiString):integer;
              stdcall;external 'WINPPLA.DLL';
    function  A_Prn_Text_Chinese(x:integer; y:integer; fonttype:integer; id_name:AnsiString; data:AnsiString;
              mem_mode:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Prn_Text_TrueType(x:integer; y:integer; FSize:integer; FType:AnsiString; Fspin:integer;
              FWeight:integer; FItalic:integer; FUnline:integer; FStrikeOut:integer; id_name:AnsiString;
              data:AnsiString; mem_mode:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Prn_Text_TrueType_W(x:integer; y:integer; FHeight:integer; FWidth:integer;
              FType:AnsiString; Fspin:integer; FWeight:integer; FItalic:integer; FUnline:integer;
              FStrikeOut:integer; id_name:AnsiString; data:AnsiString; mem_mode:integer):integer;
              stdcall;external 'WINPPLA.DLL';
    function  A_Set_Backfeed(back:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_BMPSave(nSave:integer; pstrBMPFName:AnsiString):integer;stdcall;
              external 'WINPPLA.DLL';
    function  A_Set_Cutting(cutting:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_Darkness(heat:UINT):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_DebugDialog(nEnable:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_Feed(rate:char):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_Form(formfile:AnsiString; form_name:AnsiString; mem_mode:integer):integer;stdcall;
              external 'WINPPLA.DLL';
    function  A_Set_Margin(position:integer; margin:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_Prncomport(baud:integer; parity:integer; data:integer; stop:integer):integer;
              stdcall;external 'WINPPLA.DLL';
    function  A_Set_Prncomport_PC(nBaudRate:integer; nByteSize:integer; nParity:integer;
              nStopBits:integer; nDsr:integer; nCts:integer; nXonXoff:integer):integer;stdcall;
              external 'WINPPLA.DLL';
    function  A_Set_Sensor_Mode(type_Renamed:char; continuous:integer):integer;stdcall;
              external 'WINPPLA.DLL';
    function  A_Set_Speed(speed:char):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_Syssetting(transfer:integer; cut_peel:integer; length:integer; zero:integer;
              pause:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_Unit(unit_Renamed:char):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_Gap(gap:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_Logic(logic:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_ProcessDlg(nShow:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_ErrorDlg(nShow:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_LabelVer(centiInch:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_GetUSBBufferLen():integer;stdcall;external 'WINPPLA.DLL';
    function  A_EnumUSB(buf:PAnsiChar):integer;stdcall;external 'WINPPLA.DLL';
    function  A_CreateUSBPort(nPort:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_CreatePort(nPortType:integer; nPort:integer; filename:AnsiString):integer;stdcall;
              external 'WINPPLA.DLL';
    function  A_Clear_MemoryEx(nMode:integer):integer;stdcall;external 'WINPPLA.DLL';
    Procedure A_Set_Mirror();stdcall;external 'WINPPLA.DLL';
    function  A_Bar2d_RSS(x:integer; y:integer; ori:integer; ratio:integer; height:integer;
              rtype:char; mult:integer; seg:integer; data1:AnsiString; data2:AnsiString):integer;stdcall;
              external 'WINPPLA.DLL';
    function  A_Bar2d_QR_M(x:integer; y:integer; ori:integer; mult:char; value:integer; model:integer;
              error:char; mask:integer; dinput:char; mode:char; numeric:integer; data:AnsiString):integer;
              stdcall;external 'WINPPLA.DLL';
    function  A_Bar2d_QR_A(x:integer; y:integer; ori:integer; mult:char; value:integer; mode:char;
              numeric:integer; data:AnsiString):integer;stdcall;external 'WINPPLA.DLL';
    function  A_GetNetPrinterBufferLen():integer;stdcall;external 'WINPPLA.DLL';
    function  A_EnumNetPrinter(buf:PAnsiChar):integer;stdcall;external 'WINPPLA.DLL';
    function  A_CreateNetPort(nPort:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Prn_Text_TrueType_Uni(x:integer; y:integer; FSize:integer; FType:AnsiString; Fspin:integer;
              FWeight:integer; FItalic:integer; FUnline:integer; FStrikeOut:integer; id_name:AnsiString;
              data:PWideChar; format:integer; mem_mode:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Prn_Text_TrueType_UniB(x:integer; y:integer; FSize:integer; FType:AnsiString; Fspin:integer;
              FWeight:integer; FItalic:integer; FUnline:integer; FStrikeOut:integer; id_name:AnsiString;
              data:PWideChar; format:integer ; mem_mode:integer):integer;stdcall;external 'WINPPLA.DLL';
    function  A_GetUSBDeviceInfo(nPort:integer; pDeviceName:PAnsiChar; pDeviceNameLen:PInteger;
              pDevicePath:PAnsiChar; pDevicePathLen:PInteger):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Set_EncryptionKey(encryptionKey:AnsiString):integer;stdcall;external 'WINPPLA.DLL';
    function  A_Check_EncryptionKey(decodeKey:AnsiString; encryptionKey:AnsiString;
              dwTimeoutms:integer):integer;stdcall;external 'WINPPLA.DLL';

procedure TForm1.Button1Click(Sender: TObject);
var
     ret,nLen,sw : integer;
     pbuf : array[0..127] of AnsiChar;
     ver : PAnsiChar;
     strmsg : string;
     len1,len2 : integer;
     buf1,buf2 : AnsiString;
     buff1 : array[0..127] of WideChar;
     himage : HBITMAP;
begin
     // Test code start
     // open port.
     // dll version.
     ver := A_Get_DLL_Version(0);

     // search port.
     nLen := A_GetUSBBufferLen() + 1;
     strmsg := 'DLL ' + ver + dpCrLf;   // only sample coding, not smart.
     If nLen > 1 then
     begin
         len1 := 128;
         len2 := 128;
         SetLength(buf1,len1);
         SetLength(buf2,len2);
         A_EnumUSB(pbuf);
         A_GetUSBDeviceInfo(1, PAnsiChar(buf1), @len1, PAnsiChar(buf2), @len2);
         sw := 1;
         If 0 < sw then
                ret := A_CreatePrn(12, PAnsiChar(buf2)) // open usb.
         else
                ret := A_CreateUSBPort(1); // must call A_GetUSBBufferLen() function fisrt.
         If 0 < ret then
             strmsg := strmsg + 'Open USB fail!'
         else
         begin
             SetLength(buf1,len1);
             SetLength(buf2,len2);
             strmsg := strmsg + 'Open USB:' + dpCrLf+ 'Device name: ';
             strmsg := strmsg + buf1;
             strmsg := strmsg + dpCrLf+ 'Device path: ';
             strmsg := strmsg + buf2;
             //sw := 2;
             If 2 = sw then
             begin
                //get printer status.
                pbuf[0] := #$01;
                pbuf[1] := #$46;
                pbuf[2] := #$0D;
                pbuf[3] := #$0A;
                A_WriteData(1, pbuf, 4);   //<SOH>F
                ret := A_ReadData(pbuf, 2, 1000);
             end;
         end;
     end
     else
     begin
         CreateDirectory(PChar(szSavePath), nil);
         ret := A_CreatePrn(0, szSaveFile);   // open file.
         strmsg := strmsg + 'Open ' + szSaveFile;
         if 0 < ret then
             strmsg := strmsg + ' file fail!'
         else
             strmsg := strmsg + ' file succeed!';
     end;
     ShowMessage(strmsg);
     If 0 < ret then
         exit;

     // sample setting.
     A_Set_DebugDialog(1);
     A_Set_Unit('n');
     A_Set_Syssetting(1, 0, 0, 0, 0);
     A_Set_Darkness(8);
     A_Del_Graphic(1, '*');   // delete all picture.
     A_Clear_Memory();   // clear memory.
     A_WriteData(0, sznop2, StrLen(PAnsiChar(sznop2)));
     A_WriteData(1, sznop1, StrLen(PAnsiChar(sznop1)));

     // draw box.
     A_Draw_Box('A', 10, 10, 380, 280, 4, 4);
     A_Draw_Line('A', 200, 10, 4, 280);

     // print text, true type text.
     A_Prn_Text(20, 30, 1, 2, 0, 1, 1, 'N', 2, 'PPLA Lib Example');
     A_Prn_Text_TrueType(20, 60, 30, 'Arial', 1, 400, 0, 0, 0, 'AA', 'TrueType Font', 1);   // save in ram.
     A_Prn_Text_TrueType_W(20, 90, 20, 20, 'Times New Roman', 1, 400, 0, 0, 0, 'AB', 'TT_W: 多字元測試', 1);

     StringToWideChar('TT_Uni: 多字元測試', buff1, 128);  // Converts double-byte characters to UNICODE(wide characters).
     buff1[13] := #$0000;   // null.
     A_Prn_Text_TrueType_Uni(20, 120, 30, 'Times New Roman', 1, 400, 0, 0, 0, 'AC', buff1, 1, 1);   // UTF-16

     buff1[0] := #$FEFF;   // UTF-16.
     StringToWideChar('TT_UniB: 多字元測試', buff1+1, 128);  // Converts double-byte characters to UNICODE(wide characters).
     buff1[15] := #$0000;   // null.
     A_Prn_Text_TrueType_UniB(20, 150, 30, 'Times New Roman', 1, 400, 0, 0, 0, 'AD', buff1, 0, 1);   // Byte Order Mark.

     // barcode.
     A_Prn_Barcode(220, 60, 1, 'A', 0, 0, 20, 'B', 1, '1234');
     A_Bar2d_QR_A(220, 100, 1, '3', 10, 'N', 0, 'QR CODE');

     // picture.
     A_Get_Graphic_ColorBMP(220, 150, 1, 'B', 'bb.bmp');   // Color bmp file to ram.
     A_Get_Graphic_ColorBMPEx(220, 170, 200, 150, 2, 1, 'B', 'bb1', 'bb.bmp');//180 angle.
     himage := LoadImage(0,'bb.bmp',IMAGE_BITMAP,0,0,LR_LOADFROMFILE);
     A_Get_Graphic_ColorBMP_HBitmap(300, 150, 250, 80, 1, 1, 'B', 'bb2', himage);//90 angle.
     If 0 <> himage then
         DeleteObject(himage);

     // output.
     A_Print_Out(1, 1, 2, 1);   // copy 2.

     // close port.
     A_ClosePrn();
end;

end.

I run it and the function A_GetUSBBufferLen() always returns 0 showing the following message:

That's the question. Why A_GetUSBBufferLen() didn't work? Did I forget something?

It is very suspicious that a function in a DLL has AnsiString parameters. If this is really so (i.e. the DLLs were specifically written for Delphi), you should use SharedMem as first used unit in your .dpr file. Much more likely is that you should pass a `PAnsiChar`. See my articles: [DLL dos and don'ts](http://rvelthuis.de/articles/articles-dlls.html) and [Pitffals of converting](http://rvelthuis.de/articles/articles-convert.html). The fact that you also have a `string` (which maps to UnicodeString, in Delphi 2009 and later) as parameter makes this even more suspicious. — Rudy Velthuis, Jul 16 '18 at 15:32
Just downloaded the file. The `AnsiString` parameter declarations are wrong. The VC examples use `char *`, which maps to `PAnsiChar`. The entire example doesn't make sense. I don't have the hardware, so I can't test anything, but you better read the VC docs (text files) and use those to do your own conversion (see my articles) of the functions. — Rudy Velthuis, Jul 16 '18 at 15:44
I also see several `Char` parameters being declared (`mode`, etc) in the Delphi code. `Char` is `WideChar` (16bit) in D2009+, so if the parameters are actually `char` (8bit) in the DLL, you need to use `AnsiChar` instead. — Remy Lebeau, Jul 16 '18 at 16:03
@RudyVelthuis, based on your comments, I've created a new project and declared only the function `A_GetUSBBufferLen()`. Unfortunately it still returns 0 (zero) even using ShareMem. — Daniel Grillo, Jul 16 '18 at 17:45
ShareMem is only necessary if you use AnsiStrings. But the C declaration shows you must declare the strings as PAnsiChar, and the buffer len function doesn't seem to need strings. I can't debug your code, so you'll have to do that yourself. — Rudy Velthuis, Jul 16 '18 at 20:44

Why call function A_GetUSBBufferLen() from winppla.dll doesn't work on Delphi Tokyo?

0 Answers0