National Instruments Low-Cost Multifunction I/O Board for ISA... User manual

© Copyright 1992, 1996 National Instruments Corporation.
All Rights Reserved.
Lab-PC+
User Manual
Low-Cost Multifunction I/O Board for ISA
June 1996 Edition
Part Number 320502B-01

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[phone]
Technical support fax: [phone]
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Warranty
The Lab-PC+ board 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
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OF NATIONAL INSTRUMENTS SHALL BE LIMITED TO THE AMOUNT THERETOFORE PAID BY THE CUSTOMER.
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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
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in part, without the prior written consent of National Instruments Corporation.
Trademarks
LabVIEW®, NI-DAQ®, RTSI®, and SCXI™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 v Lab-PC+ User Manual
Contents
About This Manual ...........................................................................................................xi
Organization of the Lab-PC+ User Manual..................................................................xi
Conventions Used in This Manual.................................................................................xii
National Instruments Documentation ............................................................................xiii
Customer Communication .............................................................................................xiii
Chapter 1
Introduction .........................................................................................................................1-1
About the Lab-PC+ ........................................................................................................1-1
What You Need to Get Started ......................................................................................1-1
Software Programming Choices ....................................................................................1-2
LabVIEW and LabWindows/CVI Application Software ..................................1-2
NI-DAQ Driver Software...................................................................................1-2
Register-Level Programming.............................................................................1-3
Optional Equipment .......................................................................................................1-4
Unpacking ......................................................................................................................1-4
Chapter 2
Configuration and Installation ......................................................................................2-1
Board Configuration ......................................................................................................2-1
PC Bus Interface ................................................................................................2-1
Base I/O Address Selection................................................................................2-3
DMA Channel Selection ....................................................................................2-6
Interrupt Selection..............................................................................................2-7
Analog I/O Configuration ..............................................................................................2-8
Analog Output Configuration ............................................................................2-9
Bipolar Output Selection........................................................................2-9
Unipolar Output Selection .....................................................................2-10
Analog Input Configuration...............................................................................2-10
Input Mode.............................................................................................2-10
DIFF Input (Four Channels) ..................................................................2-11
RSE Input (Eight Channels, Factory Setting) ........................................2-12
NRSE Input (Eight Channels)................................................................2-13
Analog Input Polarity Configuration .................................................................2-13
Bipolar Input Selection ..........................................................................2-13
Unipolar Input Selection ........................................................................2-14
Hardware Installation.....................................................................................................2-15

Contents
Lab-PC+ User Manual vi © National Instruments Corporation
Chapter 3
Signal Connections ............................................................................................................3-1
I/O Connector Pin Description.......................................................................................3-1
Signal Connection Descriptions.........................................................................3-2
Analog Input Signal Connections ......................................................................3-4
Types of Signal Sources.................................................................................................3-5
Floating Signal Sources .....................................................................................3-5
Ground-Referenced Signal Sources...................................................................3-6
Input Configurations ......................................................................................................3-6
Differential Connection Considerations (DIFF Configuration).........................3-6
Differential Connections for Grounded Signal Sources ....................................3-7
Differential Connections for Floating Signal Sources .......................................3-8
Single-Ended Connection Considerations .........................................................3-10
Single-Ended Connections for Floating Signal Sources
(RSE Configuration) ..........................................................................................3-10
Single-Ended Connections for Grounded Signal Sources
(NRSE Configuration) .......................................................................................3-11
Common-Mode Signal Rejection Considerations..............................................3-12
Analog Output Signal Connections....................................................................3-12
Digital I/O Signal Connections..........................................................................3-13
Port C Pin Connections..........................................................................3-15
Timing Specifications ............................................................................3-16
Mode 1 Input Timing .............................................................................3-18
Mode 1 Output Timing ..........................................................................3-19
Mode 2 Bidirectional Timing.................................................................3-20
Timing Connections...........................................................................................3-21
Data Acquisition Timing Connections...................................................3-21
General-Purpose Timing Signal Connections and
General-Purpose Counter/Timing Signals .............................................3-24
Cabling...........................................................................................................................3-28
Chapter 4
Theory of Operation ..........................................................................................................4-1
Functional Overview......................................................................................................4-1
PC I/O Channel Interface Circuitry ...............................................................................4-2
Analog Input and Data Acquisition Circuitry................................................................4-4
Analog Input Circuitry.......................................................................................4-5
Data Acquisition Timing Circuitry ....................................................................4-5
Single-Channel Data Acquisition...........................................................4-6
Multiple-Channel (Scanned) Data Acquisition......................................4-6
Data Acquisition Rates...........................................................................4-7
Analog Output Circuitry ................................................................................................4-9
Digital I/O Circuitry.......................................................................................................4-10
Timing I/O Circuitry ......................................................................................................4-11

Contents
© National Instruments Corporation vii Lab-PC+ User Manual
Chapter 5
Calibration.............................................................................................................................5-1
Calibration Equipment Requirements............................................................................5-1
Calibration Trimpots......................................................................................................5-2
Analog Input Calibration ...............................................................................................5-3
Board Configuration ..........................................................................................5-4
Bipolar Input Calibration Procedure..................................................................5-4
Unipolar Input Calibration Procedure................................................................5-5
Analog Output Calibration.............................................................................................5-6
Board Configuration ..........................................................................................5-6
Bipolar Output Calibration Procedure ...............................................................5-6
Unipolar Output Calibration Procedure .............................................................5-8
Appendix A
Specifications .......................................................................................................................A-1
Appendix B
OKI 82C53 Data Sheet .....................................................................................................B-1
Appendix C
OKI 82C55A Data Sheet .................................................................................................C-1
Appendix D
Register Map and Descriptions......................................................................................D-1
Appendix E
Register-Level Programming .........................................................................................E-1
Appendix F
Customer Communication...............................................................................................F-1
Glossary ......................................................................................................................Glossary-1
Index .................................................................................................................................Index-1

Contents
Lab-PC+ User Manual viii © National Instruments Corporation
Figures
Figure 1-1. The Relationship between the Programming Environment,
NI-DAQ, and Your Hardware............................................................................1-3
Figure 2-1. Parts Locator Diagram .......................................................................................2-2
Figure 2-2. Example Base I/O Address Switch Settings ......................................................2-4
Figure 2-3. DMA Jumper Settings for DMA Channel 3 (Factory Setting) ..........................2-6
Figure 2-4. DMA Jumper Settings for Disabling DMA Transfers.......................................2-7
Figure 2-5. Interrupt Jumper Setting IRQ5 (Factory Setting) ..............................................2-7
Figure 2-6. Interrupt Jumper Setting for Disabling Interrupts..............................................2-8
Figure 2-7. Bipolar Output Jumper Configuration (Factory Setting) ...................................2-9
Figure 2-8. Unipolar Output Jumper Configuration .............................................................2-10
Figure 2-9. DIFF Input Configuration ..................................................................................2-12
Figure 2-10. RSE Input Configuration ...................................................................................2-12
Figure 2-11. NRSE Input Configuration.................................................................................2-13
Figure 2-12. Bipolar Input Jumper Configuration (Factory Setting)......................................2-14
Figure 2-13. Unipolar Input Jumper Configuration................................................................2-14
Figure 3-1. Lab-PC+ I/O Connector Pin Assignments.........................................................3-2
Figure 3-2. Lab-PC+ Instrumentation Amplifier..................................................................3-5
Figure 3-3. Differential Input Connections for Grounded Signal Sources...........................3-8
Figure 3-4. Differential Input Connections for Floating Sources.........................................3-9
Figure 3-5. Single-Ended Input Connections for Floating Signal Sources...........................3-11
Figure 3-6. Single-Ended Input Connections for Grounded Signal Sources........................3-12
Figure 3-7. Analog Output Signal Connections....................................................................3-13
Figure 3-8. Digital I/O Connections .....................................................................................3-15
Figure 3-9. EXTCONV* Signal Timing...............................................................................3-21
Figure 3-10. Posttrigger Data Acquisition Timing Case 1 .....................................................3-22
Figure 3-11. Posttrigger Data Acquisition Timing Case 2 .....................................................3-22
Figure 3-12. Pretrigger Data Acquisition Timing...................................................................3-23
Figure 3-13. EXTUPDATE* Signal Timing for Updating DAC Output...............................3-24
Figure 3-14. EXTUPDATE* Signal Timing for Generating Interrupts .................................3-24
Figure 3-15. Event-Counting Application with External Switch Gating................................3-25
Figure 3-16. Frequency Measurement Application ................................................................3-26
Figure 3-17. General-Purpose Timing Signals .......................................................................3-27
Figure 4-1. Lab-PC+ Block Diagram ...................................................................................4-1
Figure 4-2. PC I/O Interface Circuitry Block Diagram ........................................................4-3
Figure 4-3. Analog Input and Data Acquisition Circuitry Block Diagram ..........................4-4
Figure 4-4. Analog Output Circuitry Block Diagram...........................................................4-9
Figure 4-5. Digital I/O Circuitry Block Diagram .................................................................4-10
Figure 4-6. Timing I/O Circuitry Block Diagram.................................................................4-12
Figure 4-7. Two-Channel Interval-Scanning Timing ...........................................................4-13
Figure 4-8. Single-Channel Interval Timing.........................................................................4-14
Figure 4-9. Counter Block Diagram .....................................................................................4-14
Figure 5-1. Calibration Trimpot Location Diagram .............................................................5-2
Figure E-1. Control-Word Format with Control-Word Flag Set to 1 ...................................E-24
Figure E-2. Control-Word Format with Control-Word Flag Set to 0 ...................................E-24

Contents
© National Instruments Corporation ix Lab-PC+ User Manual
Tables
Table 2-1. PC Bus Interface Factory Settings .....................................................................2-3
Table 2-2. Switch Settings with Corresponding Base I/O Address and
Base I/O Address Space.....................................................................................2-5
Table 2-3. DMA Channels for the Lab-PC+ .......................................................................2-6
Table 2-4. Analog I/O Jumper Settings...............................................................................2-9
Table 2-5. Input Configurations Available for the Lab-PC+ ..............................................2-11
Table 3-1. Recommended Input Configurations for Ground-Referenced and
Floating Signal Sources .....................................................................................3-6
Table 3-2. Port C Signal Assignments ................................................................................3-16
Table 4-1. Analog Input Settling Time Versus Gain...........................................................4-7
Table 4-2. Lab-PC+ Maximum Recommended Data Acquisition Rates ............................4-8
Table 4-3. Bipolar Analog Input Signal Range Versus Gain..............................................4-8
Table 4-4. Unipolar Analog Input Signal Range Versus Gain............................................4-8
Table 5-1. Voltage Values of ADC Input............................................................................5-4
Table D-1. Lab-PC+ Register Map ......................................................................................D-2
Table E-1. Unipolar Input Mode A/D Conversion Values (Straight Binary Coding) .........E-4
Table E-2. Bipolar Input Mode A/D Conversion Values (Two’s Complement Coding)....E-4
Table E-3. Analog Output Voltage Versus Digital Code
(Unipolar Mode, Straight Binary Coding) .........................................................E-21
Table E-4. Analog Output Voltage Versus Digital Code
(Bipolar Mode, Two’s Complement Coding)....................................................E-22
Table E-5. Mode 0 I/O Configurations................................................................................E-26
Table E-6. Port C Set/Reset Control Words ........................................................................E-33

© National Instruments Corporation xi Lab-PC+ User Manual
About This Manual
This manual describes the electrical and mechanical aspects of the Lab-PC+ and contains
information concerning its operation and programming.
The Lab-PC+ is a low-cost multifunction analog, digital, and timing I/O board for PC compatible
computers.
Organization of the Lab-PC+ User Manual
The Lab-PC+ User Manual is organized as follows:
• Chapter 1, Introduction, describes the Lab-PC+; lists what you need to get started; describes
the optional software and optional equipment; and explains how to unpack the Lab-PC+.
• Chapter 2, Configuration and Installation, describes the Lab-PC+ jumper configuration and
installation of the Lab-PC+ board in your computer.
• Chapter 3, Signal Connections, describes how to make input and output signal connections to
your Lab-PC+ board via the board I/O connector.
• Chapter 4, Theory of Operation, contains a functional overview of the Lab-PC+ and explains
the operation of each functional unit making up the Lab-PC+. This chapter also explains the
basic operation of the Lab-PC+ circuitry.
• Chapter 5, Calibration, discusses the calibration procedures for the Lab-PC+ analog input
and analog output circuitry.
• Appendix A, Specifications, lists the specifications of the Lab-PC+.
• Appendix B, OKI 82C53 Data Sheet, contains the manufacturer data sheet for the
OKI 82C53 System Timing Controller integrated circuit (OKI Semiconductor). This circuit
is used on the Lab-PC+.
• Appendix C, OKI 82C55A Data Sheet, contains the manufacturer data sheet for the
OKI 82C55A Programmable Peripheral Interface integrated circuit (OKI Semiconductor).
This circuit is used on the Lab-PC+.
• Appendix D, Register Map and Descriptions, describes in detail the address and function of
each of the Lab-PC+ registers.
• Appendix E, Register-Level Programming, contains important information about
programming the Lab-PC+.
• Appendix F, Customer Communication, contains forms you can use to request help from
National Instruments or to comment on our products and manuals.

About This Manual
Lab-PC+ User Manual xii © National Instruments Corporation
• The Glossary contains an alphabetical list and description of terms used in this manual,
including abbreviations, acronyms, metric prefixes, mnemonics, and symbols.
• The Index contains an alphabetical list of key terms and topics used in this manual, including
the page where each one can be found.
Conventions Used in This Manual
The following conventions appear in this manual.
8253 8253 refers to the OKI Semiconductor 82C53 System Timing Controller
integrated circuit.
< > Angle brackets containing numbers separated by an ellipsis represent a
range of values associated with a bit or signal name (for example,
BDIO<3...0>).
bold Bold text denotes the names of menus, menu items, parameters, dialog
boxes, dialog box buttons or options, icons, windows [Windows OS],
Windows 95 tabs or pages, or LEDs.
bold italic Bold italic text denotes a note, caution, or warning.
italic Italic text denotes emphasis, a cross reference, or an introduction to a key
concept. This text denotes text for which you supply the appropriate word
or value, such as in Windows 3.x.
italic monospace Italic text in this font denotes that you must supply the appropriate words
or values in the place of these items.
monospace Bold text in this font denotes the messages and responses that the
computer automatically prints to the screen. This font also emphasizes
lines of code that are unique from the other examples.
monospace Text in this font denotes text or characters that you should literally enter
from the keyboard, sections of code, programming examples, and syntax
examples. This font also is used for the proper names of disk drives,
paths, directories, programs, subprograms, subroutines, device names,
functions, operations, variables, filenames, and extensions, and for
statements and comments taken from program code.
NI-DAQ NI-DAQ refers to the NI-DAQ software for PC compatibles unless
otherwise noted.
paths Paths are denoted using backslashes (\) to separate drive names,
directories, folders, and files.
[ ] Square brackets enclose optional items (for example, [response]).
The Glossary lists abbreviations, acronyms, metric prefixes, mnemonics, symbols, and terms.

About this Manual
© National Instruments Corporation xiii Lab-PC+ User Manual
National Instruments Documentation
The Lab-PC+ User Manual is one piece of the documentation set for your DAQ system. You
could have any of several types of manuals depending on the hardware and software in your
system. Use the 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 documentation—Examples of software documentation you may have are the
LabVIEW and LabWindows®/CVI documentation sets and the NI-DAQ documentation.
After you set up your hardware system, use either the application software (LabVIEW or
LabWindows/CVI) or the NI-DAQ documentation to help you write your application. If you
have a large and complicated system, it is worthwhile to look through the software
documentation before you configure your hardware.
• Accessory installation guides or manuals—If you are using accessory products, read the
terminal block and cable assembly installation guides. 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.
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 F, Customer
Communication, at the end of this manual.

© National Instruments Corporation 1-1 Lab-PC+ User Manual
Chapter 1
Introduction
This chapter describes the Lab-PC+; lists what you need to get started; describes the optional
software and optional equipment; and explains how to unpack the Lab-PC+.
About the Lab-PC+
The Lab-PC+ is a low-cost multifunction analog, digital, and timing I/O board for the PC. The
Lab-PC+ contains a 12-bit successive-approximation ADC with eight analog inputs, which can
be configured as eight single-ended or four differential channels. The Lab-PC+ also has
two12-bit DACs with voltage outputs, 24 lines of TTL-compatible digital I/O, and six 16-bit
counter/timer channels for timing I/O.
The low cost of a system based on the Lab-PC+ makes it ideal for laboratory work in industrial
and academic environments. The multichannel analog input is useful in signal analysis and data
logging. The 12-bit ADC is useful in high-resolution applications such as chromatography,
temperature measurement, and DC voltage measurement. The analog output channels can be
used to generate experiment stimuli and are also useful for machine and process control and
analog function generation. The 24 TTL-compatible digital I/O lines can be used for switching
external devices such as transistors and solid-state relays, for reading the status of external digital
logic, and for generating interrupts. The counter/timers can be used to synchronize events,
generate pulses, and measure frequency and time. The Lab-PC+, used in conjunction with the
PC, is a versatile, cost-effective platform for laboratory test, measurement, and control.
Detailed specifications of the Lab-PC+ are in Appendix A, Specifications.
What You Need to Get Started
To set up and use your Lab-PC+ board, you will need the following:
Lab-PC+ board
Lab-PC+ User Manual
One of the following software packages and documentation:
NI-DAQ for PC compatibles
LabVIEW
LabWindows/CVI
Your computer

Introduction Chapter 1
Lab-PC+ User Manual 1-2 © National Instruments Corporation
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, NI-DAQ, or register-level
programming.
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.
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 signal conditioning or accessory products. 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
(timed D/A conversion), digital I/O, counter/timer operations, SCXI, RTSI, 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.

Chapter 1 Introduction
© National Instruments Corporation 1-3 Lab-PC+ User Manual
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. Whether you are using conventional programming
languages, LabVIEW, or LabWindows/CVI, your application uses the NI-DAQ driver software,
as illustrated in Figure 1-1.
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
You can use your Lab-PC+ board, together with other PC, AT, EISA, DAQCard, and DAQPad
Series DAQ and SCXI hardware, with NI-DAQ software for PC compatibles.
Register-Level Programming
The final option for programming any National Instruments DAQ hardware is to write register-
level 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 as easy and as flexible as register-level
programming and can save weeks of development time.

Introduction Chapter 1
Lab-PC+ User Manual 1-4 © National Instruments Corporation
Optional Equipment
National Instruments offers a variety of products to use with your Lab-PC+ board, including
cables, connector blocks, and other accessories, as follows:
• Cables and cable assemblies, shielded and ribbon
• Connector blocks, shielded and unshielded 50, 68, and 100-pin screw terminals
• Real Time System Integration (RTSI) bus cables
• Signal Condition eXtension 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 3072 channels.
• Low channel count signal conditioning modules, boards, and accessories, including
conditioning for strain gauges and RTDs, simultaneous sample and hold, and relays
For more specific information about these products, refer to your National Instruments catalogue
or call the office nearest you.
Unpacking
Your Lab-PC+ 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.

© National Instruments Corporation 2-1 Lab-PC+ User Manual
Chapter 2
Configuration and Installation
This chapter describes the Lab-PC+ jumper configuration and installation of the Lab-PC+ board
in your computer.
Board Configuration
The Lab-PC+ contains six jumpers and one DIP switch to configure the PC bus interface and
analog I/O settings. The DIP switch is used to set the base I/O address. Two jumpers are used as
interrupt channel and DMA selectors. The remaining four jumpers are used to change the analog
input and analog output circuitry. The parts locator diagram in Figure 2-1 shows the Lab-PC+
jumper settings. Jumpers W3 and W4 configure the analog input circuitry. Jumpers W1 and W2
configure the analog output circuitry. Jumpers W6 and W5 select the DMA channel and the
interrupt level, respectively.
PC Bus Interface
The Lab-PC+ is configured at the factory to a base I/O address of hex 260, to use DMA
Channel 3, and to use interrupt level 5. These settings (shown in Table 2-1) are suitable for most
systems. If your system, however, has other hardware at this base I/O address, DMA channel, or
interrupt level, you will need to change these settings on the other hardware or on the Lab-PC+
as described in the following pages. Record your settings in the Lab-PC+ Hardware and
Software Configuration Form in Appendix F.

Configuration and Installation Chapter 2
Lab-PC+ User Manual 2-2 © National Instruments Corporation
1
2
3 4 7
8
9
5 6
13 12 11 10 
1 Assembly Number 5 W2 8 Serial Number 11 W6
2 Spare Fuse 6 W3 9 J1 12 W5
3 U1 7 W4 10 Fuse 13 Product Name
4W1
Figure 2-1. Parts Locator Diagram

Chapter 2 Configuration and Installation
© National Instruments Corporation 2-3 Lab-PC+ User Manual
Table 2-1. PC Bus Interface Factory Settings
Lab-PC+ Board Default Settings Hardware Implementation
Base I/O Address Hex 260
A5
1 2 3 4 5
O
N
O
F
F
U1
A9 A8 A7 A6
DMA Channel DMA Channel 3
(factory setting) W6: DRQ3, DACK*3
Interrupt Level Interrupt level 5 selected
(factory setting) W5: Row 5
Note: The shaded portion indicates the side of the switch that is pressed down.
Base I/O Address Selection
The base I/O address for the Lab-PC+ is determined by the switches at position U1 (see
Figure 2-1). The switches are set at the factory for the base I/O address hex 260. This factory
setting is used as the default base I/O address value by National Instruments software packages
for use with the Lab-PC+. The Lab-PC+ uses the base I/O address space hex 260 through 27F
with the factory setting.
Note: Verify that this space is not already used by other equipment installed in your
computer. If any equipment in your computer uses this base I/O address space, you
must change the base I/O address of the Lab-PC+ or of the other device. If you change
the Lab-PC+ base I/O address, you must make a corresponding change to any software
packages you use with the Lab-PC+. For more information about your computer’s
I/O, refer to your computer’s technical reference manual.
Each switch in U1 corresponds to one of the address lines A9 through A5. 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.