outportb in WIN32

A group at Queen's University is trying to implement the (out,in)portb command in an WIN32 program. We are using the command to directly control the digital port of a National Instruments A/D card. In a 16-bit Dos application, we could simply use the (in,out)portb command, but when trying to create a 32-bit windows GUI application, Borland C++ 5.0 won't compile the program. Checking the help manual and the compatibility list for certain commands, it lists that (in,out)portb is not avaliable to WIN32. Is there any way around this in a WIN95 environment to use the outportb command in a 32-bit application. If so, how would one do it? (does it possibly involve accessing the EISA.vxd file in windows 95?)

Thanks for such consideration,

Yael Maguire
Queen's University, Kingston, Ontario.
yaelAsked:
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glittleConnect With a Mentor Commented:
2 possible methods that should work for Win95.

1.  If your compiler has inline assembly, use it to insert the proper assembly calls.

unsigned char inportb(int port)
{
    _asm {
        mov    dx, port
        xor      ax,ax
        in         al, dx
    }
    return;
}

void outputb(int port, char ch)
{
    _asm {
        mov    dx, port
        xor       ax,ax
        mov    al, ch
        out       dx, al
    }
    return;
}

These examples are for Microsoft C, but should give you the basic concept.  


2.  Write 2 assembly language functions and link them with your C program.  The assembly used above can be the kernel code for these functions.  You simply need to know how to interface assembly with Borlannd's C++ 5.0 environment.

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