Accessing Hardware Ports

[Tim Mathias]

Hi,

I need to access the parallel ports to communicate with a custom made hardware
device. I did this successfully using Turbo C++ (DOS) a few years ago. I
now need to port it to Win95 and Win NT. Where do I start?
I think I may need to write a device driver. I've tried using assembly "in
al, dx". This seems OK in Win95 but causes a privileged intruction fault
in WinNT. Any help would be much appreciated.

Cheers,
Tim.

[jonnin]

Nt device access is not trivial. It is easy in 98. You need the nt driver
sdk and a month to read and play with it. I think there is also a 98/95
driver sdk.

A driver is not necessary but could make it nicer. A driver would allow
any windows program to use the device. The port routines would be required
if only your program wants to use it.

Visual c has some built in port access routines for limited use; maybe that
will work? do a search on visual c parallel port and see if you can find
source code. I have some for serial ports if you want that; its untested
on NT but should work with it.

I do not recommend assembly for the NT stuff. You must ask NT's permission
for device access and perform detailed OS stuff before using the device.
(this will unlock those instructions.)
Sorry no details; I have only done this from a distance.


"Tim Mathias" <tim.mathias@talk21.com> wrote:
>
>Hi,
>
>I need to access the parallel ports to communicate with a custom made hardware
>device. I did this successfully using Turbo C++ (DOS) a few years ago. I
>now need to port it to Win95 and Win NT. Where do I start?
>I think I may need to write a device driver. I've tried using assembly
"in
>al, dx". This seems OK in Win95 but causes a privileged intruction fault
>in WinNT. Any help would be much appreciated.
>
>Cheers,
>Tim.