parallel port problem

[yarajit]

I am facing problem in parallel port interfacing . The parallel port woks well with visual basic. I have copied inpout32.dll file in system32 folder. But the simple program written in c doesnot execute data to parallel port.

The program is as follows:
#include<iostream.h>
#include<stdio.h>
#include<conio.h>
#include<dos.h>

void main()
{

outportb(0x378,0xaa);
sleep(1);
cout<<"data sending .......";
getch();

}

I have changed also the compatibility mode for windows98 mode i .exe file. but no change in the output.

what is the problem out there . can anybody help me.

whereas the circuit works well in the visual basic program.

 

[jhbbunch]

Windows 2000 and Windows XP will not allow direct reads and writes to ports. The code in outputb() will do nothing. That is why people write portIO dll files. They do some sneaky tampering with an access privilege map (or whatever it is) that MS uses to grant or deny access to ports.