Writing a parallel port control program with C++ Builder

Hello,
I have rencently read the article "Programming Parallel Port in Win2k an XP Problem" and that's the same question I am facing right now.
Can anybody please tell me what to do to build a program that controls my device via parallel cable? I was just trying to write a small program and to see if my board reacts to my program. I have tried to use "UserPort" but error occurs when running inportb (at __asm in al,dx).
My sample code is listed below, please tell me if there is anything I missed:

//---------------------------------------------------------------------------
#include <windows.h>
#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
static BOOL bPrivException = FALSE;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
void outport(UINT portid, UINT value)
{
  __asm mov edx,portid;
  __asm mov eax,value;
  __asm out dx,ax;
}
void outportb(UINT portid, BYTE value)
{
  __asm mov edx,portid
  __asm mov al,value
  __asm out dx,al
}

BYTE inportb(UINT portid)
{
  unsigned char value;
 
  __asm mov edx,portid
  __asm in al,dx
  __asm mov value,al
  return value;
}

UINT inport(UINT portid)
{
  int value=0;
  __asm mov edx,portid
  __asm in ax,dx
  __asm mov value,eax
  return value;
}
LONG WINAPI HandlerExceptionFilter ( EXCEPTION_POINTERS *pExPtrs )
{

      if (pExPtrs->ExceptionRecord->ExceptionCode == EXCEPTION_PRIV_INSTRUCTION)
      {
            pExPtrs->ContextRecord->Eip ++; // Skip the OUT or IN instruction that caused the exception
            bPrivException = TRUE;
            return EXCEPTION_CONTINUE_EXECUTION;
      }
      else
            return EXCEPTION_CONTINUE_SEARCH;
}
BOOL StartUpIoPorts(UINT PortToAccess)
{
    HANDLE hUserPort;
    hUserPort = CreateFile("\\\\.\\UserPort", GENERIC_READ, 0, NULL,OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
    CloseHandle(hUserPort); // Activate the driver
    Sleep(100); // We must make a process switch
    SetUnhandledExceptionFilter(HandlerExceptionFilter);
    bPrivException = FALSE;
    inportb(PortToAccess);  // Try to access the given port address
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
    StartUpIoPorts(0x378);
}
//---------------------------------------------------------------------------

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