Interfacing to the

							                          Interfacing to the
                     IBM-PC Parallel Printer Port
The original IBM-PC's Parallel Printer Port had a total of 12 digital outputs and
5 digital inputs accessed via 3 consecutive 8-bit ports in the processor's I/O space.

      8 output pins accessed via the DATA Port
      5 input pins (one inverted) accessed via the STATUS Port
      4 output pins (three inverted) accessed via the CONTROL Port
      The remaining 8 pins are grounded




                           25-way Female D-Type Connector



Various enhanced versions of the original specification have been introduced over the
years

      Bi-directional (PS/2)
      Enhanced Parallel Port (EPP)
      Extended Capability Port (ECP)

so now the original is commonly referred to as the

                            Standard Parallel Port (SPP)

           Introduction • Programming Considerations • Registers and Pinouts

           Reading and Writing Data • How many ports are present and where
Examples

       A Digital JoyStick • An LCD Module • Stepper Motor Control
       Analog-to-Digital and Digital-to-Analog Conversion
       Francis J. Deck's Two-Chip I/O Expander
       Jim Fuller's Robotics Resources include a Simplified Output Interface and a 4-
        way Input/Output Interface
       Kris Heidenstrom's LPTCAP parallel print capture system
       Kyle C. Quinnell's Building an 8-bit PC-Based Logic Analyzer

Project Proposals

       Controlling an LCD module
       PC-to-PC file transfer
       Data logging system for a PC

Other Sources of Information

       Zhahai Stewart's IBM Parallel Port FAQ/Tutorial version 0.96
       Craig Peacock's Beyond Logic covers both Parallel and Serial Ports and more...
       Peter H. Anderson's Use of a PC Printer Port for Control and Data Acquisition
       Warp Nine Enginering's Introduction to the IEEE 1284 Parallel Port Standard
       more

                          back to my Documents & Information links

last updated: 26-Jan-98 Ian Harries <ih@doc.ic.ac.uk>