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Windows NT parallel port communication.

        My objective is to stream data through the parallel port.  The
operating system platform is NT 4.0.  I am using an assembly example
that works fine in window '95 but seems to generate a privilege set
error in NT.

Example:

        procedure TForm1.writebyte(value:byte);
        asm
                mov dx, 0378
                mov al,value
                out dx, al
        end;

        If there is anyone with any insight into this problem it would
be greatly appreciated.

Andrew Cates
aca...@wabang.com

 

Re:Windows NT parallel port communication.


        Windows NT is considered a secure operating system.  You do not have
direct access to the hardware (much like UNIX).  You are granted access to
the hardware via various device drivers but this access is controlled.  In
NT, the typical user does not required direct access to the hardware.  Your
assembly code is still sound but it needs to be included in a device driver
and installed in NT (or maybe a software service; these might be the same
thing, then again maybe not).  
--
Rob Tanner B.E.,B.Sc.
Design Engineer
WestBau Technologies, Inc.

Andrew Cates <aca...@wabang.com> wrote in article
<335b91ed.32522...@news.lakeheadu.ca>...

Quote

>    My objective is to stream data through the parallel port.  The
> operating system platform is NT 4.0.  I am using an assembly example
> that works fine in window '95 but seems to generate a privilege set
> error in NT.

> Example:

>    procedure TForm1.writebyte(value:byte);
>    asm
>                    mov dx, 0378
>                    mov al,value
>                    out dx, al
>    end;

>    If there is anyone with any insight into this problem it would
> be greatly appreciated.

> Andrew Cates
> aca...@wabang.com

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