National Instruments PC-DIO-96 User Manual

© Copyright 1990, 1995 National Instruments Corporation.

PC-DIO-96

Digital I/O Board for the IBM PC/XT/AT

User Manual

September 1995 Edition

Part Number 320289B-01

All Rights Reserved.

National Instruments Corporate Headquarters

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[phone]
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[phone]

Limited Warranty

The PC-DIO-96 is warranted against defects in materials and workmanship for a period of one year from the date of

shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace
equipment that proves to be defective during the warranty period. This warranty includes parts and labor.

The media on which you receive National Instruments software are warranted not to fail to execute programming
instructions, due to defects in materials and workmanship, for a period of 90 days from date of shipment, as
evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace software
media that do not execute programming instructions if National Instruments receives notice of such defects during
the warranty period. National Instruments does not warrant that the operation of the software shall be uninterrupted
or error free.

A Return Material Authorization (RMA) number must be obtained from the factory and clearly marked on the
outside of the package before any equipment will be accepted for warranty work. National Instruments will pay the
shipping costs of returning to the owner parts which are covered by warranty.

National Instruments believes that the information in this manual is accurate. The document has been carefully
reviewed for technical accuracy. In the event that technical or typographical errors exist, National Instruments
reserves the right to make changes to subsequent editions of this document without prior notice to holders of this
edition. The reader should consult National Instruments if errors are suspected. In no event shall National
Instruments be liable for any damages arising out of or related to this document or the information contained in it.

EXCEPT AS SPECIFIED HEREIN, NATIONAL INSTRUMENTS MAKES NO WARRANTIES, EXPRESS OR
IMPLIED, AND SPECIFICALLY DISCLAIMS ANY WARRANTY OF MERCHANTABILITY OR FITNESS
FOR A PARTICULAR PURPOSE. CUSTOMER'S RIGHT TO RECOVER DAMAGES CAUSED BY FAULT
OR NEGLIGENCE ON THE PART OF NATIONAL INSTRUMENTS SHALL BE LIMITED TO THE AMOUNT
THERETOFORE PAID BY THE CUSTOMER. NATIONAL INSTRUMENTS WILL NOT BE LIABLE FOR
DAMAGES RESULTING FROM LOSS OF DATA, PROFITS, USE OF PRODUCTS, OR INCIDENTAL OR
CONSEQUENTIAL DAMAGES, EVEN IF ADVISED OF THE POSSIBILITY THEREOF. This limitation of the
liability of National Instruments will apply regardless of the form of action, whether in contract or tort, including
negligence. Any action against National Instruments must be brought within one year after the cause of action
accrues. National Instruments shall not be liable for any delay in performance due to causes beyond its reasonable
control. The warranty provided herein does not cover damages, defects, malfunctions, or service failures caused by
owner's failure to follow the National Instruments installation, operation, or maintenance instructions; owner's
modification of the product; owner's abuse, misuse, or negligent acts; and power failure or surges, fire, flood,
accident, actions of third parties, or other events outside reasonable control.

Copyright

Under the copyright laws, this publication may not be reproduced or transmitted in any form, electronic or
mechanical, including photocopying, recording, storing in an information retrieval system, or translating, in whole or
in part, without the prior written consent of National Instruments Corporation.

Trademarks

LabVIEW®, NI-DAQ®, and GPIB-PCII™ are trademarks of National Instruments Corporation.
Product and company names listed are trademarks or trade names of their respective companies.

WARNING REGARDING MEDICAL AND CLINICAL USE

OF NATIONAL INSTRUMENTS PRODUCTS

National Instruments products are not designed with components and testing intended to ensure a level of reliability
suitable for use in treatment and diagnosis of humans. Applications of National Instruments products involving
medical or clinical treatment can create a potential for accidental injury caused by product failure, or by errors on the
part of the user or application designer. Any use or application of National Instruments products for or involving
medical or clinical treatment must be performed by properly trained and qualified medical personnel, and all
traditional medical safeguards, equipment, and procedures that are appropriate in the particular situation to prevent
serious injury or death should always continue to be used when National Instruments products are being used.
National Instruments products are NOT intended to be a substitute for any form of established process, procedure, or
equipment used to monitor or safeguard human health and safety in medical or clinical treatment.

© National Instruments Corporation

Contents

Chapter 1
About This Manual

............................................................................................................ v

Organization of This Manual ........................................................................................ v

Conventions Used in This Manual ................................................................................ vi

National Instruments Documentation............................................................................ vii

Related Documentation ................................................................................................. vii

Chapter 1
Introduction

.......................................................................................................................... 1-1

About the PC-DIO-96 ................................................................................................... 1-1

What You Need to Get Started...................................................................................... 1-2

Software Programming Choices.................................................................................... 1-2

LabVIEW and LabWindows/CVI Application Software.................................. 1-2

NI-DAQ Driver Software .................................................................................. 1-3

Register-Level Programming ............................................................................ 1-4

Optional Equipment ...................................................................................................... 1-4

Cabling .............................................................................................................. 1-4

Unpacking ..................................................................................................................... 1-5

Chapter 2
Configuration and Installation

..................................................................................... 2-1

Board Configuration...................................................................................................... 2-1

Base I/O Address Settings................................................................................. 2-2

Interrupt Level Selection ................................................................................... 2-5

Installation ..................................................................................................................... 2-5

Signal Connections........................................................................................................ 2-6

I/O Connector Pin Description .......................................................................... 2-7

I/O Connector Signal Connection Descriptions ................................................ 2-8

Port C Pin Assignments......................................................................... 2-8

Cable Assembly Connectors ............................................................................. 2-9

Digital I/O Signal Connections ......................................................................... 2-12

Power Connections............................................................................................ 2-13

Timing Specifications........................................................................................ 2-14

Mode 1 Input Timing ............................................................................ 2-15

Mode 1 Output Timing.......................................................................... 2-16

Mode 2 Bidirectional Timing ................................................................ 2-17

Chapter 3
Theory of Operation

.......................................................................................................... 3-1

Data Transceivers .......................................................................................................... 3-2

PC I/O Channel Control Circuitry................................................................................. 3-2

82C55A Programmable Peripheral Interface ................................................................ 3-2

8253 Programmable Interval Timer .............................................................................. 3-2

Interrupt Control Circuitry ............................................................................................ 3-2

Digital I/O Connector.................................................................................................... 3-3

v PC-DIO-96 User Manual

Contents

Chapter 4
Register-Level Programming

Introduction ................................................................................................................... 4-1

Register Map ................................................................................................................. 4-2

Register Descriptions .................................................................................................... 4-3

Register Description for the 82C55A................................................................ 4-3

Register Description for the 8253 ..................................................................... 4-4

Register Description for the Interrupt Control Registers .................................. 4-5

Interrupt Control Register 1 .................................................................. 4-6

Interrupt Control Register 2 .................................................................. 4-8

Programming Considerations for the 82C55A.............................................................. 4-9

Modes of Operation for the 82C55A................................................................. 4-9

Mode 0 ................................................................................................... 4-9

Mode 1 ................................................................................................... 4-9

Mode 2 ................................................................................................... 4-10

Single Bit Set/Reset Feature.................................................................. 4-10

Mode 0—Basic I/O ........................................................................................... 4-10

Mode 0 Programming Example ............................................................ 4-11

Mode 1—Strobed Input..................................................................................... 4-12

Mode 1 Input Programming Example ................................................... 4-14

Mode 1—Strobed Output .................................................................................. 4-15

Mode 1 Output Programming Example ................................................ 4-16

Mode 2—Bidirectional Bus............................................................................... 4-17

Mode 2 Programming Example ............................................................ 4-19

Interrupt Programming Examples for the 82C55A ........................................... 4-19

Programming Considerations for the 8253 ................................................................... 4-21

General Information .......................................................................................... 4-21

Interrupt Programming Example for the 8253 .................................................. 4-22

Interrupt Handling ......................................................................................................... 4-28

......................................................................................... 4-1

Appendix A
Specifications

........................................................................................................................ A-1

Appendix B
OKI 82C55A Data Sheet

.................................................................................................. B-1

Appendix C
AMD 8253 Data Sheet

....................................................................................................... C-1

Appendix D
Customer Communication

.............................................................................................. D-1

Glossary ...................................................................................................................... Glossary-1

Index.................................................................................................................................. Index-1

PC-DIO-96 User Manual vi © National Instruments Corporation

Contents

Figures

Figure 1-1. The Relationship between the Programming Environment, NI-DAQ, and Your

Hardware ........................................................................................................... 1-3

Figure 2-1. PC-DIO-96 Parts Locator Diagram ................................................................... 2-2

Figure 2-2. Example Base I/O Address Switch Settings...................................................... 2-3

Figure 2-3. Interrupt Jumper Setting for IRQ5 (Factory Setting) ........................................ 2-5

Figure 2-4. Digital I/O Connector Pin Assignments............................................................ 2-7

Figure 2-5. Cable-Assembly Connector Pinout for Pins 1 through 50 ................................ 2-10

Figure 2-6. Cable-Assembly Connector Pinout for Pins 51 through 100 ............................ 2-11

Figure 2-7. Digital I/O Connections..................................................................................... 2-13

Figure 3-1. PC-DIO-96 Block Diagram............................................................................... 3-1

Figure 4-1. Control Word Formats for the 82C55A ............................................................ 4-3

Figure 4-2. Control-Word Format for the 8253 ................................................................... 4-4

Tables

Table 2-1. PC-DIO-96 Factory-Set Switch and Jumper Settings ....................................... 2-1

Table 2-2. Switch Settings with Corresponding Base I/O Address

and Base I/O Address Space ............................................................................. 2-4

Table 2-3. Port C Signal Assignments................................................................................ 2-9

Table 4-1. PC-DIO-96 Address Map.................................................................................. 4-2

Table 4-2. Port C Set/Reset Control Words........................................................................ 4-4

Table 4-3. Mode 0 I/O Configurations ............................................................................... 4-11

Table A-1. Maximum Average Transfer Rates for the PC-DIO-96 .................................... A-3

© National Instruments Corporation vii PC-DIO-96 User Manual

© National Instruments Corporation

Contents

Chapter 1
About This Manual

............................................................................................................ v

Organization of This Manual ........................................................................................ v

Conventions Used in This Manual ................................................................................ vi

National Instruments Documentation............................................................................ vii

Related Documentation ................................................................................................. vii

Chapter 1
Introduction

.......................................................................................................................... 1-1

About the PC-DIO-96 ................................................................................................... 1-1

What You Need to Get Started...................................................................................... 1-2

Software Programming Choices.................................................................................... 1-2

LabVIEW and LabWindows/CVI Application Software.................................. 1-2

NI-DAQ Driver Software .................................................................................. 1-3

Register-Level Programming ............................................................................ 1-4

Optional Equipment ...................................................................................................... 1-4

Cabling .............................................................................................................. 1-4

Unpacking ..................................................................................................................... 1-5

Chapter 2
Configuration and Installation

..................................................................................... 2-1

Board Configuration...................................................................................................... 2-1

Base I/O Address Settings................................................................................. 2-2

Interrupt Level Selection ................................................................................... 2-5

Installation ..................................................................................................................... 2-5

Signal Connections........................................................................................................ 2-6

I/O Connector Pin Description .......................................................................... 2-7

I/O Connector Signal Connection Descriptions ................................................ 2-8

Port C Pin Assignments......................................................................... 2-8

Cable Assembly Connectors ............................................................................. 2-9

Digital I/O Signal Connections ......................................................................... 2-12

Power Connections............................................................................................ 2-13

Timing Specifications........................................................................................ 2-14

Mode 1 Input Timing ............................................................................ 2-15

Mode 1 Output Timing.......................................................................... 2-16

Mode 2 Bidirectional Timing ................................................................ 2-17

Chapter 3
Theory of Operation

.......................................................................................................... 3-1

Data Transceivers .......................................................................................................... 3-2

PC I/O Channel Control Circuitry................................................................................. 3-2

82C55A Programmable Peripheral Interface ................................................................ 3-2

8253 Programmable Interval Timer .............................................................................. 3-2

Interrupt Control Circuitry ............................................................................................ 3-2

Digital I/O Connector.................................................................................................... 3-3

v PC-DIO-96 User Manual

Contents

Chapter 4
Register-Level Programming

Introduction ................................................................................................................... 4-1

Register Map ................................................................................................................. 4-2

Register Descriptions .................................................................................................... 4-3

Register Description for the 82C55A................................................................ 4-3

Register Description for the 8253 ..................................................................... 4-4

Register Description for the Interrupt Control Registers .................................. 4-5

Interrupt Control Register 1 .................................................................. 4-6

Interrupt Control Register 2 .................................................................. 4-8

Programming Considerations for the 82C55A.............................................................. 4-9

Modes of Operation for the 82C55A................................................................. 4-9

Mode 0 ................................................................................................... 4-9

Mode 1 ................................................................................................... 4-9

Mode 2 ................................................................................................... 4-10

Single Bit Set/Reset Feature.................................................................. 4-10

Mode 0—Basic I/O ........................................................................................... 4-10

Mode 0 Programming Example ............................................................ 4-11

Mode 1—Strobed Input..................................................................................... 4-12

Mode 1 Input Programming Example ................................................... 4-14

Mode 1—Strobed Output .................................................................................. 4-15

Mode 1 Output Programming Example ................................................ 4-16

Mode 2—Bidirectional Bus............................................................................... 4-17

Mode 2 Programming Example ............................................................ 4-19

Interrupt Programming Examples for the 82C55A ........................................... 4-19

Programming Considerations for the 8253 ................................................................... 4-21

General Information .......................................................................................... 4-21

Interrupt Programming Example for the 8253 .................................................. 4-22

Interrupt Handling ......................................................................................................... 4-28

......................................................................................... 4-1

Appendix A
Specifications

........................................................................................................................ A-1

Appendix B
OKI 82C55A Data Sheet

.................................................................................................. B-1

Appendix C
AMD 8253 Data Sheet

....................................................................................................... C-1

Appendix D
Customer Communication

.............................................................................................. D-1

Glossary ...................................................................................................................... Glossary-1

Index.................................................................................................................................. Index-1

PC-DIO-96 User Manual vi © National Instruments Corporation

Contents

Figures

Figure 1-1. The Relationship between the Programming Environment, NI-DAQ, and Your

Hardware ........................................................................................................... 1-3

Figure 2-1. PC-DIO-96 Parts Locator Diagram ................................................................... 2-2

Figure 2-2. Example Base I/O Address Switch Settings...................................................... 2-3

Figure 2-3. Interrupt Jumper Setting for IRQ5 (Factory Setting) ........................................ 2-5

Figure 2-4. Digital I/O Connector Pin Assignments............................................................ 2-7

Figure 2-5. Cable-Assembly Connector Pinout for Pins 1 through 50 ................................ 2-10

Figure 2-6. Cable-Assembly Connector Pinout for Pins 51 through 100 ............................ 2-11

Figure 2-7. Digital I/O Connections..................................................................................... 2-13

Figure 3-1. PC-DIO-96 Block Diagram............................................................................... 3-1

Figure 4-1. Control Word Formats for the 82C55A ............................................................ 4-3

Figure 4-2. Control-Word Format for the 8253 ................................................................... 4-4

Tables

Table 2-1. PC-DIO-96 Factory-Set Switch and Jumper Settings ....................................... 2-1

Table 2-2. Switch Settings with Corresponding Base I/O Address

and Base I/O Address Space ............................................................................. 2-4

Table 2-3. Port C Signal Assignments................................................................................ 2-9

Table 4-1. PC-DIO-96 Address Map.................................................................................. 4-2

Table 4-2. Port C Set/Reset Control Words........................................................................ 4-4

Table 4-3. Mode 0 I/O Configurations ............................................................................... 4-11

Table A-1. Maximum Average Transfer Rates for the PC-DIO-96 .................................... A-3

© National Instruments Corporation vii PC-DIO-96 User Manual

© National Instruments Corporation

About This Manual

This manual describes the mechanical and electrical aspects of the PC-DIO-96 and contains
information concerning its operation and programming. The PC-DIO-96 is a 96-bit parallel
digital I/O interface designed around four OKI Semiconductor (OKI) 82C55A programmable
peripheral interface (PPI) chips. The PC-DIO-96 also includes an Advanced Micro Devices
(AMD) 8253 counter/timer which can be used to send periodic interrupts to the host system. The
PC-DIO-96 is a member of the National Instruments PC Series of PC I/O Channel expansion
boards for the PC computer family. These boards are designed for high-performance data
acquisition and control for applications in laboratory testing, production testing, and industrial
process monitoring and control.

This manual describes installation, theory of operation, and basic programming considerations
for the PC-DIO-96. The example programs included are written in C and assembly language.

Organization of This Manual

The PC-DIO-96 User Manual is organized as follows:

• Chapter 1, Introduction, describes the PC-DIO-96, lists what you need to get started,
describes software programming choices, optional equipment, and custom cables, and
explains how to unpack the PC-DIO-96.

• Chapter 2, Configuration and Installation, describes the PC-DIO-96 jumper configuration,
installing the PC-DIO-96 board in your computer, signal connections to the PC-DIO-96
board, and cabling instructions.

• Chapter 3, Theory of Operation, explains the basic operation of the PC-DIO-96 circuitry.

• Chapter 4, Register-Level Programming, describes in detail the address and function of each
of the PC-DIO-96 control and status registers. This chapter also includes important
information about register-level programming the PC-DIO-96.

• Appendix A, Specifications, lists the specifications of the PC-DIO-96.

• Appendix B, OKI 82C55A Data Sheet, contains the manufacturer data sheet for the
OKI 82C55A (OKI Semiconductor) CMOS programmable peripheral interface. This
interface is used on the PC-DIO-96 board.

• Appendix C, AMD 8253 Data Sheet, contains the manufacturer data sheet for the AMD 8253
integrated circuit. This circuit is used on the PC-DIO-96 board.

• Appendix D, Customer Communication, contains forms you can use to request help from
National Instruments or to comment on our products.

ix PC-DIO-96 User Manual

Preface

bold italic

monospace

• The Glossary contains an alphabetical list and description of terms used in this manual,

• The Index alphabetically lists the topics in this manual, including the page where you can

Conventions Used in This Manual

The following conventions are used in this manual:
bold Bold text denotes menus, menu items, or dialog box buttons or options.

italic Italic text denotes emphasis, a cross reference, or an introduction to a key

including abbreviations, acronyms, metric prefixes, mnemonics, symbols, and terms.

find each one.

Bold italic text denotes a note, caution, or warning.

concept.
Lowercase text in this font denotes text or characters that are to be literally

input from the keyboard, sections of code, programming examples, and
syntax examples. This font is also used for the proper names of disk
drives, paths, directories, programs, subprograms, subroutines, device
names, functions, variables, filenames, and extensions, and for statements
and comments taken from program code.

NI-DAQ NI-DAQ is used throughout this manual to refer to the NI-DAQ software

for PC computers unless otherwise noted

OKI 82C55A OKI 82C55A refers to the OKI 82C55A (OKI Semiconductor) CMOS

programmable peripheral interface.

PC PC refers to the IBM PC/XT, the IBM PC AT, and compatible computers,

as well as EISA personal computers.

PPI x PPI x, where the x is replaced by A, B, C, or D, refers to one of the four

programmable peripheral interface (PPI) chips on the PC-DIO-96.

SCXI SCXI stands for Signal Conditioning eXtensions for Instrumentation and

is a National Instruments product line designed to perform front-end signal
conditioning for National Instruments plug-in DAQ boards.

< > Angle brackets containing numbers separated by an ellipses represent a

range, signal, or port (for example, ACH<0..7> stands for ACH0 through
ACH7).

Abbreviations, acronyms, metric prefixes, mnemonics, and symbols are listed in the Glossary.

PC-DIO-96 User Manual x © National Instruments Corporation

Preface

National Instruments Documentation

The PC-DIO-96 User Manual is one piece of the documentation set for your data acquisition
(DAQ) system. You could have any of several types of manuals, depending on the hardware and
software in your system. Use the different types of manuals you have as follows:

• Getting Started with SCXI—If you are using SCXI, this is the first manual you should read.
It gives an overview of the SCXI system and contains the most commonly needed
information for the modules, chassis, and software.

• Your SCXI hardware user manuals—If you are using SCXI, read these manuals next for
detailed information about signal connections and module configuration. They also explain
in greater detail how the module works and contain application hints.

• Your DAQ hardware user manuals—These manuals have detailed information about the
DAQ hardware that plugs into or is connected to your computer. Use these manuals for
hardware installation and configuration instructions, specification information about your
DAQ hardware, and application hints.

• Software manuals—Examples of software manuals you may have are the LabVIEW and
LabWindows
NI-DAQ supports LabWindows for DOS). After you set up your hardware system, use either
the application software (LabVIEW or LabWindows/CVI) manuals or the NI-DAQ manuals
to help you write your application. If you have a large and complicated system, it is
worthwhile to look through the software manuals before you configure your hardware.

®

/CVI manual sets and the NI-DAQ manuals (a 4.6.1 or earlier version of

• Accessory installation guides or manuals—If you are using accessory products, read the
terminal block and cable assembly installation guides or accessory board user manuals. They
explain how to physically connect the relevant pieces of the system. Consult these guides
when you are making your connections.

• SCXI chassis manuals—If you are using SCXI, read these manuals for maintenance
information on the chassis and installation instructions.

Related Documentation

The following document contains information that you may find helpful as you read this manual:

• IBM Personal Computer XT Technical Reference manual

Customer Communication

National Instruments wants to receive your comments on our products and manuals. We are
interested in the applications you develop with our products, and we want to help if you have
problems with them. To make it easy for you to contact us, this manual contains comment and
configuration forms for you to complete. These forms are in Appendix D, Customer

Communication, at the end of this manual.

© National Instruments Corporation xi PC-DIO-96 User Manual

© National Instruments Corporation

Chapter 1

Introduction

This chapter describes the PC-DIO-96, lists what you need to get started, describes software
programming choices, optional equipment, and custom cables, and explains how to unpack the
PC-DIO-96.

About the PC-DIO-96

Thank you for purchasing the National Instruments PC-DIO-96. The PC-DIO-96 is a 96-bit,
parallel, digital, I/O interface for the PC. Four 82C55A PPI chips control the 96 bits of digital
I/O. The 82C55A can operate in either a unidirectional or bidirectional mode and can generate
interrupt requests to the host computer. The 82C55A can be programmed for almost any 8-bit or
16-bit digital I/O application. All digital I/O is through a standard, 100-pin, male connector.

The PC-DIO-96 can be used in a wide range of digital I/O applications. With the PC-DIO-96,
any PC can be interfaced to any of the following:

• Other computers

- Another PC with a National Instruments PC-DIO-96, PC-DIO-24, or AT-DIO-32F

- IBM Personal System/2 with a National Instruments MC-DIO-24 or MC-DIO-32F

- Macintosh II with a National Instruments NB-DIO-24 or NB-DIO-32F

- Any other computer with an 8-bit or 16-bit parallel interface

• Centronics-compatible printers and plotters

• Panel meters

• Instruments and test equipment with BCD readouts and/or controls

• Opto-isolated, solid-state relays and I/O module mounting racks

Note: The PC-DIO-96 cannot sink sufficient current to drive the SSR-OAC-5 and

SSR-OAC-5A output modules. However, it can drive the SSR-ODC-5 output module
and all SSR input modules available from National Instruments.

If you need to drive a SSR-OAC-5 or SSR-OAC-5A, you can either use a non-inverting
digital buffer chip between the PC-DIO-96 and the SSR backplane, or you can use a
DIO-23F or MIO Series board with appropriate connections (e.g., SC-205X and
cables).

With the PC-DIO-96, a PC can serve as a digital I/O system controller for laboratory testing,
production testing, and industrial process monitoring and control.

Detailed specifications of the PC-DIO-96 are in Appendix A, Specifications.

1-1 PC-DIO-24 User Manual

Introduction Chapter 1

What You Need to Get Started

To set up and use your PC-DIO-96, you will need the following:

PC-DIO-96 board

PC-DIO-96 User Manual

One of the following software packages and documentation:

NI-DAQ for PC compatibles
LabVIEW for Windows
LabWindows/CVI for Windows

Your computer

Software Programming Choices

There are several options to choose from when programming your National Instruments DAQ
and SCXI hardware. You can use LabVIEW, LabWindows/CVI, or NI-DAQ. A 4.6.1 or earlier
version of NI-DAQ supports LabWindows for DOS.

LabVIEW and LabWindows/CVI Application Software

LabVIEW and LabWindows/CVI are innovative program development software packages for
data acquisition and control applications. LabVIEW uses graphical programming, whereas
LabWindows/CVI enhances traditional programming languages. Both packages include
extensive libraries for data acquisition, instrument control, data analysis, and graphical data
presentation.

LabVIEW features interactive graphics, a state-of-the-art user interface, and a powerful graphical
programming language. The LabVIEW Data Acquisition VI Library, a series of VIs for using
LabVIEW with National Instruments DAQ hardware, is included with LabVIEW. The LabVIEW
Data Acquisition VI Libraries are functionally equivalent to the NI-DAQ software.

LabWindows/CVI features interactive graphics, a state-of-the-art user interface, and uses the
ANSI standard C programming language. The LabWindows/CVI Data Acquisition Library, a
series of functions for using LabWindows/CVI with National Instruments DAQ hardware, is
included with the NI-DAQ software kit. The LabWindows/CVI Data Acquisition libraries are
functionally equivalent to the NI-DAQ software.

Using LabVIEW or LabWindows/CVI software will greatly reduce the development time for
your data acquisition and control application.

PC-DIO-24 User Manual 1-2 © National Instruments Corporation

Chapter 1 Introduction

LabWindows/CVI

(PC or Sun 

SPARCstation)

LabVIEW 

(PC, Macintosh, or 

Sun SPARCstation)

Conventional 

Programming 

Environment 

(PC, Macintosh, or 

Sun SPARCstation)

NI-DAQ

Driver Software

DAQ or

SCXI Hardware

Personal 

Computer or 

Workstation

Figure 1-1. The Relationship between the Programming Environment,

NI-DAQ, and Your Hardware

NI-DAQ Driver Software

The NI-DAQ driver software is included at no charge with all National Instruments DAQ
hardware. NI-DAQ is not packaged with SCXI or accessory products, except for the SCXI-1200.
NI-DAQ has an extensive library of functions that you can call from your application
programming environment. These functions include routines for analog input (A/D conversion),
buffered data acquisition (high-speed A/D conversion), analog output (D/A conversion),
waveform generation, digital I/O, counter/timer operations, SCXI, RTSI, self-calibration,
messaging, and acquiring data to extended memory.

NI-DAQ has both high-level DAQ I/O functions for maximum ease of use and low-level DAQ
I/O functions for maximum flexibility and performance. Examples of high-level functions are
streaming data to disk or acquiring a certain number of data points. An example of a low-level
function is writing directly to registers on the DAQ device. NI-DAQ does not sacrifice the
performance of National Instruments DAQ devices because it lets multiple devices operate at
their peak performance.

NI-DAQ also internally addresses many of the complex issues between the computer and the
DAQ hardware such as programming interrupts and DMA controllers. NI-DAQ maintains a
consistent software interface among its different versions so that you can change platforms with
minimal modifications to your code. Figure 1-1 illustrates the relationship between NI-DAQ and
LabVIEW and LabWindows/CVI.

© National Instruments Corporation 1-3 PC-DIO-24 User Manual

Introduction Chapter 1

Register-Level Programming

The final option for programming any National Instruments DAQ hardware is to write register­level software. Writing register-level programming software can be very time-consuming and
inefficient, and is not recommended for most users.

Even if you are an experienced register-level programmer, consider using NI-DAQ, LabVIEW,
or LabWindows/CVI to program your National Instruments DAQ hardware. Using the NI-DAQ,
LabVIEW, or LabWindows/CVI software is easier than, and as flexible as, register-level
programming, and can save weeks of development time.

Optional Equipment

National Instruments offers a variety of products to use with your PC-DIO-96 board, including
cables, connector blocks, and other accessories, as follows:

• Cables and cable assemblies, shielded and ribbon

• Connector blocks, shielded and unshielded 50-pin screw terminals

• Signal conditioning eXtensions for Instrumentation (SCXI) modules and accessories for
isolating, amplifying, exciting, and multiplexing signals for relays and analog output. With
SCXI you can condition and acquire up to 3,072 channels.

• Low channel count signal conditioning modules, boards, and accessories, including
conditioning for strain gauges and RTDs, simultaneous sample and hole, and relays.

For more specific information about these products, refer to your National Instruments catalog or
call the office nearest you.

Cabling

National Instruments offers cables and accessories for you to prototype your application or to use
if you frequently change board interconnections.

The PC-DIO-96 can be interfaced to a wide range of printers, plotters, test instruments, I/O racks
and modules, screw terminal panels, and almost any device with a parallel interface. The
PC-DIO-96 digital I/O connector is a standard, 100-pin header connector. Adapters for this
header connector expand the interface to four 50-pin ribbon cables, each of which has the pinout
of a PC-DIO-24. The pin assignments of the expansion cables are compatible with the standard
24-channel I/O module mounting racks (such as those manufactured by Opto 22 and Gordos).

The CB-100 cable termination accessory is available from National Instruments for use with the
PC-DIO-96 board. This kit includes two 50-conductor, flat-ribbon cables and a connector block.
Signal input and output wires can be attached to screw terminals on the connector block and are
therefore connected to the PC-DIO-96 I/O connector.

PC-DIO-24 User Manual 1-4 © National Instruments Corporation

Chapter 1 Introduction

The CB-100 is useful for initial prototyping of an application or in situations where PC-DIO-96
interconnections are frequently changed. Once a final field wiring scheme has been developed,
however, you may want to develop your own cable. This section contains information for the
design of custom cables.

The PC-DIO-96 I/O connector is a 100-pin, Centronics-style, male, ribbon-cable header
connector. The manufacturer and the appropriate part number for this connector is as follows:

• Robinson Nugent (part number P50E-100P1-SR1-TG)

The mating connector for the PC-DIO-96 is a 100-position, polarized, Centronics-style, female,
ribbon-socket connector with strain relief. National Instruments uses a polarized (keyed)
connector to prevent inadvertent upside-down connection to the PC-DIO-96. This 100-pin
connector attaches to two 50-pin cables, each of which can be connected to a 50-pin connector
on the other end. The recommended manufacturer and the appropriate part number for the
100-pin mating connector is as follows:

• Robinson Nugent (part number P50E-100S-TG)

The recommended manufacturer part numbers for 50-pin, female, ribbon-socket connectors
suitable for use with the preceding connector are:

• Electronic Products Division/3M (part number 3425-7650)

• T&B/Ansley Corporation (part number 609-5041CE)

Recommended manufacturers and the appropriate part numbers for the standard ribbon cable
(50-conductor, 28 AWG, stranded) that can be used with both the 100-pin and the 50-pin
connectors are:

• Electronic Products Division/3M (part number 3365/50)

• T&B/Ansley Corporation (part number 171-50)

Unpacking

Your PC-DIO-96 board is shipped in an antistatic package to prevent electrostatic damage to the
board. Electrostatic discharge can damage several components on the board. To avoid such
damage in handling the board, take the following precautions:

• Ground yourself via a grounding strap or by holding a grounded object.

• Touch the antistatic package to a metal part of your computer chassis before removing the
board from the package.

• Remove the board from the package and inspect the board for loose components or any other
sign of damage. Notify National Instruments if the board appears damaged in any way. Do
not install a damaged board into your computer.

• Never touch the exposed pins of connectors.

© National Instruments Corporation 1-5 PC-DIO-24 User Manual

© National Instruments Corporation

Chapter 2

Configuration and Installation

This chapter describes the PC-DIO-96 jumper configurations, installing the PC-DIO-96 board in
your computer, signal connections to the PC-DIO-96 board, and cabling instructions.

Board Configuration

The PC-DIO-96 contains one DIP switch and one jumper to configure the base I/O address and
interrupts, respectively. The DIP switch and jumper are shown in the parts locator diagram in
Figure 2-1.

The PC-DIO-96 is configured at the factory to a base I/O address of hex 180 and to interrupt
level 5. These settings (shown in Table 2-1) are suitable for most systems. However, if your
system has other hardware at this base I/O address or interrupt level, you need to change these
settings on the PC-DIO-96 (as described in the following pages) or on the other hardware.
Record your settings in the PC-DIO-96 Hardware and Software Configuration Form in
Appendix D, Customer Communication.

Table 2-1. PC-DIO-96 Factory-Set Switch and Jumper Settings

Base I/O Address Hex 180

(factory setting)

1
2

3 4 5

A9
A8
A7
A6
A5

U26

Interrupt Level Interrupt level 5 selected

(factory setting)

W1: Row 5

(The black side indicates the side of the

switch that is pushed down.)

2-1 PC-DIO-96 User Manual

Configuration and Installation Chapter 2

W1

U26

Figure 2-1. PC-DIO-96 Parts Locator Diagram

Base I/O Address Settings

The base I/O address for the PC-DIO-96 is determined by the switches at position U26 (see
Figure 2-1). The switches are set at the factory for the I/O address hex 180. With this default
setting, the PC-DIO-96 uses the I/O address space hex 180 through 19F.

Note: Verify that this space is not already used by other equipment installed in your

computer. If any equipment in your computer uses this I/O address space, you must
change the base I/O address for the PC-DIO-96 or for the other device.

Each switch in U26 corresponds to one of the address lines A9 through A5. Thus, the range for
possible base I/O address settings is hex 000 through 3E0. Base I/O address values hex 000
through 0FF are reserved for system use. Base I/O values hex 100 through 3FF are available on
the I/O channel. A4, A3, A2, A1, and A0 are used by the PC-DIO-96 to decode accesses to the

PC-DIO-96 User Manual 2-2 © National Instruments Corporation

Chapter 2 Configuration and Installation

1
2
3 4 5

A9
A8
A7
A6
A5

U26

O

N

OFF

1
2
3 4 5

A9
A8
A7
A6
A5

U26

O

N

OFF

A. Switches Set to Default Setting (Base I/O Address Hex 180)

B. Switches Set to Base I/O Address Hex 2A0

Figure 2-2. Example Base I/O Address Switch Settings

Table 2-2 shows all possible switch settings and their corresponding address ranges.

onboard registers. On the U26 DIP switches, press the side marked OFF to select a binary value
of 1 for the corresponding address bit. Press the other side of the switch to select a binary value
of 0 for the corresponding address bit. Figure 2-2 shows two possible switch settings. The black
side indicates the side of the switch that is pushed down.

© National Instruments Corporation 2-3 PC-DIO-96 User Manual

Configuration and Installation Chapter 2

Switch Setting Base I/O Address Base I/O Address

A9 A8 A7 A6 A5 (hex) Space Used (hex)

0 0 0 0 0 000 000 - 01F
0 0 0 0 1 020 020 - 03F
0 0 0 1 0 040 040 - 05F
0 0 0 1 1 060 060 - 07F
0 0 1 0 0 080 080 - 09F
0 0 1 0 1 0A0 0A0 - 0BF
0 0 1 1 0 0C0 0C0 - 0DF
0 0 1 1 1 0E0 0E0 - 0FF
0 1 0 0 0 100 100 - 11F
0 1 0 0 1 120 120 - 13F
0 1 0 1 0 140 140 - 15F
0 1 0 1 1 160 160 - 17F
0 1 1 0 0 180 180 - 19F
0 1 1 0 1 1A0 1A0 - 1BF
0 1 1 1 0 1C0 1C0 - 1DF
0 1 1 1 1 1E0 1E0 - 1FF
1 0 0 0 0 200 200 - 21F
1 0 0 0 1 220 220 - 23F
1 0 0 1 0 240 240 - 25F
1 0 0 1 1 260 260 - 27F
1 0 1 0 0 280 280 - 29F
1 0 1 0 1 2A0 2A0 - 2BF
1 0 1 1 0 2C0 2C0 - 2DF
1 0 1 1 1 2E0 2E0 - 2FF
1 1 0 0 0 300 300 - 31F
1 1 0 0 1 320 320 - 33F
1 1 0 1 0 340 340 - 35F
1 1 0 1 1 360 360 - 37F
1 1 1 0 0 380 380 - 39F
1 1 1 0 1 3A0 3A0 - 3BF
1 1 1 1 0 3C0 3C0 - 3DF
1 1 1 1 1 3E0 3E0 - 3FF

Note: Base I/O address values 000 through 0FF hex are reserved for system use.

Base I/O address values 100 through 3FF hex are available on the I/O
channel..

Table 2-2. Switch Settings with Corresponding Base I/O Address and

Base I/O Address Space

PC-DIO-96 User Manual 2-4 © National Instruments Corporation

Chapter 2 Configuration and Installation

IRQ9
IRQ7

IRQ6
IRQ5
IRQ4
IRQ3

W1

Figure 2-3. Interrupt Jumper Setting for IRQ5 (Factory Setting)

The PC-DIO-96 can share interrupt lines with other devices because it uses a tri-state driver to
drive its selected interrupt line. For information on how to disable this driver, see Chapter 4,
Register-Level Programming.

Installation

The PC-DIO-96 can be installed in any unused 8-bit, 16-bit, or 32-bit expansion slot in your
computer. After you make any necessary changes and verify the switch and jumper settings,
record them using the PC-DIO-96 Hardware and Software Configuration Form in Appendix D,
Customer Communication. You are now ready to install the PC-DIO-96.

The following are general installation instructions, but consult the user manual or technical
reference manual of your personal computer for specific instructions and warnings. If you want
to install this board in an EISA-class computer, you can obtain a configuration file for the board
by contacting National Instruments.

1. Turn off your computer.

2. Remove the top cover or access port to the I/O channel.

3. Remove the expansion slot cover on the back panel of the computer.

Interrupt Level Selection

There is one set of jumpers for interrupt selection on the PC-DIO-96 board. W1 is used for
selecting the interrupt level. The location of this jumper is shown in Figure 2-1.

The PC-DIO-96 board can connect to any one of six interrupt lines of the PC I/O Channel:
IRQ3, IRQ4, IRQ5, IRQ6, IRQ7, or IRQ9. Select the interrupt line by setting a jumper on W1.
The default interrupt line is IRQ5. To change to another line, remove the jumper from IRQ5 and
place it on the pins for another request line. Figure 2-3 shows the default factory setting for
IRQ5.

© National Instruments Corporation 2-5 PC-DIO-96 User Manual

Configuration and Installation Chapter 2

4. Insert the PC-DIO-96 in an unused 8-bit, 16-bit, or 32-bit slot. It may be a tight fit, but do

not force the board into place.

5. Screw the mounting bracket of the PC-DIO-96 to the back panel rail of the computer.

6. Check the installation.

7. Replace the cover to the computer.

Note: If you have an ISA-class computer and you are using a configurable software package,

such as NI-DAQ, you may need to reconfigure your software to reflect any changes in
jumper or switch settings. If you have an EISA-class computer, you need to update the
computer's resource allocation (or configuration) table by reconfiguring your
computer. See your computer’s user manual for information about updating the
configuration table.

The PC-DIO-96 board is now installed and ready for operation.

Signal Connections

This section includes specifications and connection instructions for the signals given on the
PC-DIO-96 I/O connector.

Warning: Connections that exceed any of the maximum ratings of input or output signals on

the PC-DIO-96 may result in damage to the PC-DIO-96 board and to the PC.
Maximum input ratings for each signal are given in this chapter under the
discussion of that signal. National Instruments is
resulting from any such signal connections.

NOT liable for any damages

PC-DIO-96 User Manual 2-6 © National Instruments Corporation

Chapter 2 Configuration and Installation

50 100

49 99

48 98

47 97

46 96

45 95

44 94

43 93

42 92

41 91

40 90

39 89

38 88

37 87

36 86

35 85

34 84

33 83

32 82

31 81

30 80

29 79

28 78

27 77

26 76

25 75

24 74

23 73

22 72

21 71

20 70

19 69

18 68

17 67

16 66

15 65

14 64

13 63

12 62

11 61

10 60

9 59

8 58

7 57

6 56

5 55

4 54

3 53

2 52

1 51

GND GND

+5 V +5 V

BPA0 DPA0

APA0 CPA0

BPA1 DPA1

APA1 CPA1

BPA2 DPA2

APA2 CPA2

BPA3 DPA3

APA3 CPA3

BPA4 DPA4

APA4 CPA4

BPA5 DPA5

APA5 CPA5

BPA6 DPA6

APA6 CPA6

BPA7 DPA7

APA7 CPA7

BPB0 DPB0

APB0 CPB0

BPB1 DPB1

APB1 CPB1

BPB2 DPB2

APB2 CPB2

BPB3 DPB3

APB3 CPB3

BPB4 DPB4

APB4 CPB4

BPB5 DPB5

APB5 CPB5

BPB6 DPB6

APB6 CPB6

BPB7 DPB7

APB7 CPB7

BPC0 DPC0

APC0 CPC0

BPC1 DPC1

APC1 CPC1

BPC2 DPC2

APC2 CPC2

BPC3 DPC3

APC3 CPC3

BPC4 DPC4

APC4 CPC4

BPC5 DPC5

APC5 CPC5

BPC6 DPC6

APC6 CPC6

BPC7 DPC7

APC7 CPC7

Figure 2-4. Digital I/O Connector Pin Assignments

I/O Connector Pin Description

Figure 2-4 shows the pin assignments for the PC-DIO-96 digital I/O connector.

© National Instruments Corporation 2-7 PC-DIO-96 User Manual

Configuration and Installation Chapter 2

1, 3, 5, 7, 9, 11, 13,15APC<7..0> Bidirectional Data Lines for Port C of PPI A—APC7 is the

MSB, APC0 the LSB.

17, 19, 21, 23, 25,
27, 29, 31

APB<7..0> Bidirectional Data Lines for Port B of PPI A—APB7 is the

MSB, APB0 the LSB.

33, 35, 37, 39, 41,
43, 45, 47

APA<7..0> Bidirectional Data Lines for Port A of PPI A—APA7 is the

MSB, APA0 the LSB.

2, 4, 6, 8, 10, 12,
14, 16

BPC<7..0> Bidirectional Data Lines for Port C of PPI B—BPC7 is the

MSB, BPC0 the LSB.

18, 20, 22, 24, 26,
28, 30, 32

BPB<7..0> Bidirectional Data Lines for Port B of PPI B—BPB7 is the

MSB, BPB0 the LSB.

34, 36, 38, 40, 42,
44, 46, 48

BPA<7..0> Bidirectional Data Lines for Port A of PPI B—BPA7 is the

MSB, BPA0 the LSB.

51, 53, 55, 57, 59,
61, 63, 65

CPC<7..0> Bidirectional Data Lines for Port C of PPI C—CPC7 is the

MSB, CPC0 the LSB.

67, 69, 71, 73, 75,
77, 79, 81

CPB<7..0> Bidirectional Data Lines for Port B of PPI C—CPB7 is the

MSB, CPB0 the LSB.

83, 85, 87, 89, 91,
93, 95, 97

CPA<7..0> Bidirectional Data Lines for Port A of PPI C—CPA7 is the

MSB, CPA0 the LSB.

52, 54, 56, 58, 60,
62, 64, 66

DPC<7..0> Bidirectional Data Lines for Port C of PPI D—DPC7 is the

MSB, DPC0 the LSB.

68, 70, 72, 74, 76,
78, 80, 82

DPB<7..0> Bidirectional Data Lines for Port B of PPI D—DPB7 is the

MSB, DPB0 the LSB.

84, 86, 88, 90, 92,
94, 96, 98

DPA<7..0> Bidirectional Data Lines for Port A of PPI D—DPA7 is the

MSB, DPA0 the LSB.

49, 99 (see note
below)

+5 V +5 Volts—These pins are connected to the computer’s +5 VDC

supply.

50, 100 GND Ground—These pins are connected to the computer’s ground

signal.

Note: Pins 49 and 99 are connected to the +5 V PC power supply via a 1 A fuse. Replacement fuses are

available from Allied Electronics, part number 845-2007, or Littelfuse, part number 251001.

Port C Pin Assignments

The signals assigned to port C depend on the mode in which the 82C55A is programmed. In
mode 0, port C is considered as two 4-bit I/O ports. In modes 1 and 2, port C is used for status
and handshaking signals with zero, two, or three lines available for general-purpose I/O. The
following table summarizes the signal assignments of port C for each programmable mode.
Consult Chapter 4, Register-Level Programming, for programming information.

I/O Connector Signal Connection Descriptions

Pin Signal Name Description

PC-DIO-96 User Manual 2-8 © National Instruments Corporation

Chapter 2 Configuration and Installation

PC7 PC6 PC5 PC4 PC3 PC2 PC1 PC0

Mode 0

I/O I/O I/O I/O I/O I/O I/O I/O

Mode 1 Input

I/O I/O IBF

A

STBA* INTR

A

STBB* IBFB

B

INTR

B

Mode 1 Output

OBFA* ACKA* I/O I/O INTR

A

ACKB* OBFB* INTR

B

Mode 2

OBFA* ACKA* IBF

A

STBA* INTR

A

I/O I/O I/O

* Indicates that the signal is active low.

Cable Assembly Connectors

The cable assembly listed under Optional Equipment in Chapter 1 is an assembly of two 50-pin
cables and three connectors. Both cables are joined to a single connector on one end and to
individual connectors on the free ends. The connector that joins the two cables is a 100-pin
connector that plugs into the I/O connector of the PC-DIO-96. The other two connectors are
50-pin connectors, one of which is connected to pins 1 through 50 of the PC-DIO-96 I/O
connector, and the other of which is connected to pins 51 through 100 of the PC-DIO-96 I/O
connector. The cable with the label on it is connected to pins 1 through 50. Figures 2-5 and 2-6
show the pin assignments for the 50-pin connectors on the cable assembly.

Warning: During programming, note that each time a port is configured, output ports A

and C are reset to 0, and output port B is undefined.

Table 2-3. Port C Signal Assignments

Programming Mode Group A Group B

© National Instruments Corporation 2-9 PC-DIO-96 User Manual

BPA1

BPA2

BPA4

BPA5

BPA6

BPA7

BPA0

BPA3

BPB0

BPB1

BPB2

BPB3

BPB4

BPB5

BPB6

BPB7

BPC0

BPC1

BPC2

BPC3

BPC4

BPC5

BPC6

BPC7

49 50

47 48

45 46

43 44

41 42

39 40

37 38

35 36

33 34

31 32

29 30

27 28

25 26

23 24

21 22

19 20

17 18

15 16

13 14

11 12

9 10

7 8

5 6

3 4

1 2

Figure 2-5. Cable-Assembly Connector Pinout for Pins 1 through 50

of the PC-DIO-96 I/O Connector

Configuration and Installation Chapter 2

APC7
APC6

APC5
APC4

APC3

APC2
APC1
APC0

APB7

APB6

APB5

APB4

APB3

APB2

APB1
APB0
APA7

APA6
APA5

PC-DIO-96 User Manual 2-10 © National Instruments Corporation

APA4
APA3
APA2
APA1
APA0

+5 V

GND

DPA1

DPA2

DPA4

DPA5

DPA6

DPA7

DPA0

DPA3

DPB0

DPB1

DPB2

DPB3

DPB4

DPB5

DPB6

DPB7

DPC0

DPC1

DPC2

DPC3

DPC4

DPC5

DPC6

DPC7

49 50

47 48

45 46

43 44

41 42

39 40

37 38

35 36

33 34

31 32

29 30

27 28

25 26

23 24

21 22

19 20

17 18

15 16

13 14

11 12

9 10

7 8

5 6

3 4

1 2

Figure 2-6. Cable-Assembly Connector Pinout for Pins 51 through 100

of the PC-DIO-96 I/O Connector

Chapter 2 Configuration and Installation

CPC7
CPC6

CPC5
CPC4

CPC3
CPC2

CPC1
CPC0

CPB7

CPB6

CPB5
CPB4
CPB3
CPB2

CPB1
CPB0
CPA7

CPA6
CPA5

© National Instruments Corporation 2-11 PC-DIO-96 User Manual

CPA4

CPA3

CPA2

CPA1

CPA0

+5 V

GND

Configuration and Installation Chapter 2

Digital I/O Signal Connections

Pins 1 through 48 and pins 51 through 98 of the I/O connector are digital I/O signal pins. The
following specifications and ratings apply to the digital I/O lines.

Absolute maximum voltage rating -0.5 to +5.5 V with respect to GND

Digital input specifications (referenced to GND):

Input logic high voltage 2.2 V minimum 5.3 V maximum
Input logic low voltage -0.3 V minimum 0.8 V maximum
Maximum input current (0 < Vin < 5 V) -1.0 µA minimum 1.0 µA maximum

Digital output specifications (referenced to GND):
Output logic high voltage 3.7 V minimum 5.0 V maximum

at I

Output logic low voltage 0.0 V minimum 0.4 V maximum

at I

Output current 4.0 mA minimum —

at V

Output current 4.0 mA minimum —

at VOH = 2.7 V

= -2.5 mA

out

= 2.5 mA

out

= 0.5 V

OL

Figure 2-7 depicts signal connections for three typical digital I/O applications.

PC-DIO-96 User Manual 2-12 © National Instruments Corporation