IBM-PC Parallel Printer Port
Reading & Writing Data

MS-DOS, MS-Windows3.1 and MS-Windows95 console applications
but not MS-Windows95/NT

Different interpreters/compilers provide access to the I/O Ports in different ways.

• MS-QBasic

• Turbo Pascal, Delphi

• Turbo C, Borland C/C++

• Microsoft Visual C/C++

• Watcom C/C++

or you can use Debug

For full details, refer to the relevant manuals.

• Randy Rasa has written a PC Printer Port I/O Module for Borland C/C++ v3.1 which provides the low-level control of the port, implementing code to control 12 outputs and read 5 inputs.

• Kyle A. York wote an article on High-Speed Transfers on a PC Parallel Port for the C/C++ Users Journal. The accompanying source files (york.zip) are included in the November 1996 ZIPped file in their Code Archive.

Note:
I have no personal experience of I/O port access in Windows 95/NT or linux (so please don't ask). MS-DOS is sufficient for (prototyping) the kinds of control systems I am interested in.

However, I recommend our students use the DriverLINX Port I/O Driver for Win95 and WinNT, provided without charge by Scientific Software Tools, Inc. Here's the README file and a local copy (1.5MB) of the package.

Some links that might be useful

• Jan Axelson's Parallel Port Central includes information on programming I/O Port access under MS-Windows

• Vincent Himpe's free WINio / WIN95io DLL restores the INP and OUT functions missing from Visual Basic.

• Dale Edgar's PortIO95 is a Windows 95 VxD that provides a simple Application Programming Interface to the PC Parallel Port (free for non-commercial use).

• Fred Bulback's free IO16.DLL / IO.DLL provide I/O Port access for Windows 3.x / 95

• SoftCircuits' free Programming Tools and Libraries include vbasm.zip, a 16-bit DLL that provides a range of functionality including Port I/O, and win95io.zip, a tiny DLL that allows Port I/O under Windows 95.

• Dan Hoehnen's Port16 / Port32 are shareware OCXs that add I/O port access capability to Visual Basic.

• Rob Woudsma's IOPORT/NTPORT are shareware OCXs for Visual Basic under Windows 95/NT

• Herve Couplet has sent me an example of I/O Port Access in Borland C++ Builder 1.0

• Samuel Grimee's Programming the parallel port under Windows NT

• Glenn D. Jones' A Short Tutorial on Writing a DLL ( ZIPped file from Programmers Heaven)

• Frequently Asked Questions (FAQ) from the comp.os.ms-windows.programmer.vxd newsgroup

and for linux enthusiasts -

• local copy (text) of Riku Saikkonen's Linux I/O port programming mini-HOWTO (HTML)

• Linux Parallel Port Home Page

last updated: 30-Nov-98 Ian Harries <ih@doc.ic.ac.uk>