National Instruments AT-GPIB User manual

© Copyright 1991, 1995 National Instruments Corporation.
All Rights Reserved.
Getting Started with Your AT-GPIB
and the NI-488M™Software for
SCO UNIX System V/386
October 1993 Edition
Part Number 320374-01

National Instruments Corporate Headquarters
6504 Bridge Point Parkway
Austin, TX 78730-5039
[phone]
Technical support fax: [phone]
[phone]
Branch Offices:
Australia [phone], Austria [phone], Belgium 02/757.00.20,
Canada (Ontario) [phone], Canada (Québec) [phone],
Denmark 45 76 26 00, Finland (90) 527 2321, France (1) 48 14 24 24,
Germany 089/741 31 30, Italy 02/48301892, Japan [phone],
Mexico 95 800 010 0793, Netherlands 03480-33466, Norway 32-84 84 00,
Singapore 2265886, Spain (91) 640 0085, Sweden 08-730 49 70,
Switzerland 056/20 51 51, Taiwan 02 377 1200, U.K. 0635 523545

Limited Warranty
The AT-GPIB is warranted against defects in materials and workmanship
for a period of two years 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
NI-488M™is a trademark 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.

FCC/DOC Radio Frequency
Interference Compliance
This equipment generates and uses radio frequency energy and, if not
installed and used in strict accordance with the instructions in this manual,
may cause interference to radio and television reception. This equipment
has been tested and found to comply with the following two regulatory
agencies:
Federal Communications Commission
This device complies with Part 15 of the Federal Communications
Commission (FCC) Rules for a Class B digital device. A Class B device is
distinguishable from a Class A device by the appearance of an FCC ID
number located on the Class B device.
Canadian Department of Communications
This device complies with the limits for radio noise emissions from digital
apparatus set out in the Radio Interference Regulations of the Canadian
Department of Communications (DOC).
Le présent appareil numérique n’émet pas de bruits radioélectriques
dépassant les limites applicables aux appareils numériques de classe B
prescrites dans le règlement sur le brouillage radioélectrique édicté par le
ministère des communications du Canada.
Instructions to Users
These regulations are designed to provide reasonable protection against
interference from the equipment to radio and television reception in
residential areas.
There is no guarantee that interference will not occur in a particular
installation. However, the chances of interference are much less if the
equipment is installed and used according to this instruction manual.

If the equipment does cause interference to radio or television reception,
which can be determined by turning the equipment on and off, one or more
of the following suggestions may reduce or eliminate the problem.
• Operate the equipment and the receiver on different branches of your
AC electrical system.
• Move the equipment away from the receiver with which it is interfering.
• Reorient or relocate the receiver’s antenna.
• Be sure that the equipment is plugged into a grounded outlet and that
the grounding has not been defeated with a cheater plug.
Notice to user: Changes or modifications not expressly approved by
National Instruments could void the user’s authority to
operate the equipment under the FCC Rules.
If necessary, consult National Instruments or an experienced radio/television
technician for additional suggestions. The following booklet prepared by
the FCC may also be helpful: How to Identify and Resolve Radio-TV
Interference Problems. This booklet is available from the U.S. Government
Printing Office, Washington, DC 20402, Stock Number 004-000-00345-4.
Bescheinigung des Herstellers/Importeurs
Hiermit wird bescheinigt, daß die AT-GPIB in Übereinstimmung mit den
Bestimmungen der Vfg. 1046/1984 funk entstört ist.
Der Detuschen Bundespost wurde das Inverkehrbringen dieses Gerätes
angezeigt und die Berechtigung zur Überprüfung der Serie auf
Bestimmungen eingeräumt.

© National Instruments Corp. ix AT-GPIB for SCO UNIX
Contents
About This Manual ..........................................................................xiii
Organization of This Manual......................................................xiii
Conventions Used in This Manual .............................................xiv
Related Documentation ..............................................................xv
Customer Communication ..........................................................xv
Chapter 1
Introduction.........................................................................................1-1
What You Need to Get Started...................................................1-1
Software Description ..................................................................1-1
Chapter 2
Hardware Configuration and Installation..............................2-1
Step 1. Configure the Hardware...............................................2-1
Switch and Jumper Settings .........................................2-2
Base I/O Address Selection..........................................2-3
Possible Conflicts...........................................2-6
Interrupt Selection ........................................................2-8
Possible Conflicts...........................................2-11
DMA Channel Selection ..............................................2-13
Shield Ground Configuration.......................................2-18
Step 2. Install the Hardware .....................................................2-19
Chapter 3
Software Installation and Configuration ................................3-1
Step 1. Prepare for Software Installation .................................3-1
Step 2. Install the NI-488M Software ......................................3-2
A. Set Up a Working Directory...................................3-2
B. Install the Utility Files ............................................3-3
C. Install the C Library ...............................................3-3
Step 3. Load the NI-488M Driver ............................................3-3
A. Change the Software Settings.................................3-4
DMA Channel................................................3-4
Base I/O Address and Interrupt Vector
Number ..........................................................3-5
B. Install the Driver.....................................................3-5
Automatic Installation ...................................3-5
Manual Installation ........................................3-6

Contents
AT-GPIB for SCO UNIX x © National Instruments Corp.
Step 4. Configure the Software ................................................3-7
Running ibconf.............................................................3-7
Exiting ibconf...............................................................3-7
System Configuration Information...............................3-8
Step 5. Verify the Installation...................................................3-8
Removing the Driver ..................................................................3-9
Developing Your Application..................................................... 3-10
Appendix A
New NI-488M Functions ................................................................A-1
IBDEV(3) ...................................................................................A-2
IBLINES(3) ................................................................................A-4
IBLN(3) ......................................................................................A-6
Appendix B
Special Instructions for Changing the
Software Settings...............................................................................B-1
Using a Base I/O Address Different from the Software
Default Setting ............................................................................B-1
Using Interrupt Vector Number 11 or DMA Channel 5.............B-2
Appendix C
Hardware Specifications................................................................C-1
Appendix D
Customer Communication............................................................D-1
Glossary.................................................................................................G-1

Contents
© National Instruments Corp. xi AT-GPIB for SCO UNIX
Figures
Figure 2-1. AT-GPIB Parts Locator Diagram ....................................2-1
Figure 2-2. Base I/O Address Switch Settings ...................................2-4
Figure 2-3. Interrupt Jumper Settings................................................. 2-10
Figure 2-4. DMA Channel Jumper Setting......................................... 2-15
Figure 2-5. DMA Jumper Setting for No DMA Channel...................2-16
Figure 2-6. Ground Configuration Jumper Settings ...........................2-18
Tables
Table 2-1. Software and Hardware Default Settings and Available
Hardware Configurations.................................................2-2
Table 2-2. Software Default AT-GPIB Base I/O Addresses.............2-3
Table 2-3. Possible Base I/O Address Switch Settings for the
AT-GPIB..........................................................................2-5
Table 2-4. PC AT I/O Address Map .................................................2-7
Table 2-5. Software Default AT-GPIB Interrupt Request Line ........2-9
Table 2-6. PC AT Interrupt Assignment Map...................................2-11
Table 2-7. Software Default AT-GPIB DMA Channel.....................2-13
Table 2-8. DMA Channels for the AT-GPIB ....................................2-14
Table 2-9. PC AT 16-Bit DMA Channel Assignment Map ..............2-17
Table 3-1. Software Default Settings ................................................3-4
Table C-1. Electrical Characteristics .................................................C-1
Table C-2. Environmental Characteristics.........................................C-1
Table C-3. Physical Characteristics ...................................................C-1

© National Instruments Corp. xiii AT-GPIB for SCO UNIX
About This Manual
This manual contains instructions for installing and configuring the
National Instruments AT-GPIB interface board and NI-488 multitasking
software (NI-488M) driver for use with the SCO UNIX System V/386
Release 3.2.2 (or higher) or Open Desktop Release 1.0 (or higher)
Operating System. This hardware and software is intended for use on a
386-based IBM personal computer. This manual is meant to be used with
the NI-488M Software Reference Manual.
Organization of This Manual
This manual is organized as follows:
• Chapter 1, Introduction, lists what you need to get started, and briefly
describes the NI-488M software.
• Chapter 2, Hardware Configuration and Installation,contains
step-by-step instructions for configuring and installing the AT-GPIB
board in a PC AT.
• Chapter 3, Software Installation and Configuration, lists all the
programs and files located on the distribution diskette and contains the
steps for installing and configuring the NI-488M software. This
chapter also contains a description of the software configuration utility,
ibconf, and information for getting started with a GPIB application
program.
• Appendix A, New NI-488M Functions, describes three new NI-488M
functions included in the NI-488M software.
• Appendix B, Special Instructions for Changing the Software Settings,
contains special instructions for changing the base I/O address,
interrupt vector number, and DMA channel software settings.
• Appendix C, Hardware Specifications, lists the electrical,
environmental, and physical characteristics of the AT-GPIB board and
the conditions under which it should be operated.

About This Manual
AT-GPIB for SCO UNIX xiv © National Instruments Corp.
• Appendix D, Customer Communication, contains forms you can use to
request help from National Instruments or to comment on our products
and manuals.
• The Glossary contains an alphabetical list and description of terms used
in this manual, including abbreviations, acronyms, metric prefixes,
mnemonics, and symbols.
Conventions Used in This Manual
The following conventions are used in this manual.
italic Italic text denotes emphasis, a cross reference, or
an introduction to a key concept.
monospace 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.
italic monospace Italic text in this font denotes that you must
supply the appropriate words or values in place
of these items.
<> Angle brackets enclose the name of a key on the
keyboard—for example, <Shift>.
<Return> Key names are capitalized.
IEEE 488 IEEE 488 refers to the ANSI/IEEE Standard
488-1978, which defines the GPIB.
NI-488M NI-488M refers to the NI-488M software for
SCO UNIX System V/386.

About This Manual
© National Instruments Corp. xv AT-GPIB for SCO UNIX
SCO UNIX SCO UNIX refers to the SCO UNIX System
V/386 Release 3.2.2 (or higher) or Open Desktop
Release 1.0 (or higher) Operating System.
Abbreviations, acronyms, metric prefixes, mnemonics, symbols, and terms
are listed in the Glossary.
Related Documentation
The following documents contain information that you may find helpful as
you read this manual.
•Getting Started with Your AT-GPIB/TNT and NI-488.2 Software for
DOS
•UNIX System V/386 Release 3.2 Integrated Software Development
Guide
•IBM Personal Computer AT Technical Reference
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 Corp. 1-1 AT-GPIB for SCO UNIX
Chapter 1
Introduction
This chapter lists what you need to get started, and briefly describes the
NI-488M software.
The AT-GPIB is a full-function, high-performance IEEE 488 interface for a
386-based IBM personal computer (herein referred to as the PC AT) that is
equipped with 16-bit plug-in slots. The AT-GPIB makes the PC AT a
high-performance IEEE 488 Controller.
What You Need to Get Started
AT-GPIB board, which you can purchase from National Instruments
3.5 in. NI-488M Distribution Disk AT-GPIB SCO UNIX System V/386
Handler and C Interface, which comes in your kit
Shielded GPIB cables*, which you can purchase from National
Instruments:
Type X1 single-shielded cables – 1 m, 2 m, or 4 m
Type X2 double-shielded cables – 1 m, 2 m, or 4 m
* To meet FCC emission limits for this Class B device, you must use a
shielded (Type X1 or X2) GPIB cable. Operating this equipment with
a non-shielded cable may cause interference to radio and television
reception in residential areas.
Software Description
The NI-488M software is a comprehensive set of programs and drivers that
transforms any computer running SCO UNIX System V/386 Release 3.2.2
or higher or Open Desktop Release 1.0 or higher (herein referred to as SCO
UNIX System V/386) into a GPIB Controller with complete
communications and bus management capabilities. The NI-488M software
also comes with a C language interface and an interactive control program.

© National Instruments Corp. 2-1 AT-GPIB for SCO UNIX
Chapter 2
Hardware Configuration and
Installation
This chapter contains step-by-step instructions for configuring and
installing the AT-GPIB board in a PC AT.
Step 1. Configure the Hardware
Figure 2-1 shows the location of the AT-GPIB configuration jumpers and
switches.
Figure 2-1. AT-GPIB Parts Locator Diagram

Hardware Configuration and Installation Chapter 2
AT-GPIB for SCO UNIX 2-2 ©National Instruments Corp.
Because SCO UNIX defines the base I/O address, the interrupt line, and the
Direct Memory Access (DMA) channel, the hardware settings to which the
AT-GPIB board was configured at the factory are not suitable for use under
SCO UNIX System V/386. You must change the hardware jumper settings
to match the default software configuration settings given in Table 2-1.
Switch and Jumper Settings
Table 2-1 shows the software and hardware default settings and available
hardware configurations for the AT-GPIB board.
Table 2-1. Software and Hardware Default Settings and Available
Hardware Configurations
AT-GPIB
Software
Default
Settings
Hardware
Default
Settings
Available
Hardware
Configurations
Base I/O Address
(hex) 260 2C0 100 to 3E0
DMA Channel 7 5 5, 6, 7, and
Not Used
Interrupt Line (IRQ) 5 11 3, 4, 5, 6, 7, 9, 10,
11, 12, 14, 15, and
Not Used

Chapter 2 Hardware Configuration and Installation
© National Instruments Corp. 2-3 AT-GPIB for SCO UNIX
Base I/O Address Selection
The base I/O address is determined by the switches at position U25. The
switches are set at the factory for the base I/O address 2C0 hex. The
AT-GPIB board uses the I/O address space 2C0 through 2DF hex with this
setting. If you install more than one AT-GPIB board in your computer,
each board must be configured to use a unique base I/O address. The
default AT-GPIB board base I/O addresses for the NI-488M software are
shown in Table 2-2. You must change the base I/O address setting in the
hardware to match the software base I/O address setting.
Table 2-2. Software Default AT-GPIB Base I/O Addresses
Board Default Base I/O Address
First AT-GPIB (gpib0) 260 hex
Second AT-GPIB (gpib1) 240 hex
Check to determine that the software default I/O address space is not
already used by other equipment installed in your computer. If any
equipment in your computer uses this I/O address space, change the base
I/O address of either the AT-GPIB board or the other device. (See
Table 2-3 later in this chapter for other possible AT-GPIB board base I/O
address settings.)
Each switch in U25 corresponds to one of the PC AT bus address lines A9
through A5. The top switch (1) corresponds to address line A9, the next
switch from the top (2) corresponds to address line A8, and so on. The five
least significant bits of the address (A4 through A0) are used by the
AT-GPIB board to select the appropriate GPIB adapter register and cannot
be changed; therefore, bits A4 through A0 are always 00000 (binary) when
determining the base I/O address.
Press down on the side marked 1 to select a binary value of 1 for the
corresponding address bit. Press down on the side marked 0 to select a
binary value of 0 for the corresponding address bit (refer to Figure 2-2).
Figure 2-2 shows the hardware default base I/O address setting and the
setting to which you must change your hardware to match the software base
I/O address default setting. In this figure, the black side of the switch is the

Hardware Configuration and Installation Chapter 2
AT-GPIB for SCO UNIX 2-4 ©National Instruments Corp.
side you press down. Each of the address selections shows how the base
I/O address was calculated from the switch positions.
Push this side down (OFF) for logic 1
Push this side down (ON) for logic 0
Switch Set to Hardware
Default Setting

(Base I/O Address 2C0 hex)
Switch Set to Match Software
Default Setting

(Base I/O Address 260 hex)
9
8
7
6
5
U25 
ADDRESS Binary Hex
0
C
2
9
8
7
6
5
Binary Hex
0
6
2
1
0
1
1
0
0
0
0
0
0
1
0
0
1
1
0
0
0
0
0
U25 
ADDRESS
1 0
1 0
12345
OFF
12345
OFF
Figure 2-2. Base I/O Address Switch Settings

Chapter 2 Hardware Configuration and Installation
© National Instruments Corp. 2-5 AT-GPIB for SCO UNIX
To change the base I/O address press each switch to the desired position,
then check each switch to make sure it is pressed down all the way.
Table 2-3 lists the possible switch settings, the corresponding base I/O
address, and the I/O address space used for that setting.
Table 2-3. Possible Base I/O Address Switch Settings for the AT-GPIB
Switch Setting
A9 A8 A7 A6 A5 Base I/O Address (hex) I/O Address Space Used (hex)
01000 100 100 to 11F
01001 120 120 to 13F
01010 140 140 to 15F
01011 160 160 to 17F
01100 180 180 to 19F
01101 1A0 1A0to1BF
01110 1C0 1C0to1DF
01111 1E0 1E0 to 1FF
10000 200 200 to 21F
10001 220 220 to 23F
10010 240 240 to 25F
10011 260 260 to 27F
10100 280 280 to 29F
10101 2A0 2A0to2BF
10110 2C0 2C0to2DF
10111 2E0 2E0 to 2FF
11000 300 300 to 31F
11001 320 320 to 33F
11010 340 340 to 35F
11011 360 360 to 37F
11100 380 380 to 39F
(continues)

Hardware Configuration and Installation Chapter 2
AT-GPIB for SCO UNIX 2-6 ©National Instruments Corp.
Table 2-3. Possible Base I/O Address Switch Settings for the AT-GPIB
(Continued)
Switch Setting
A9 A8 A7 A6 A5 Base I/O Address (hex) I/O Address Space Used (hex)
11101 3A0 3A0to3BF
11110 3C0 3C0to3DF
11111 3E0 3E0 to 3FF
If you change the hardware base I/O address to something other than 260
hex, make sure that you make a corresponding change to the software
base I/O address setting as described under Configure the Software in
Chapter 3, Software Installation and Configuration. Also, make sure that
you record the new setting on the AT-GPIB Hardware and Software
Configuration Form in Appendix D, Customer Communication.
Possible Conflicts
Table 2-4 lists some of the I/O addresses used by other PC AT plug-in
interface boards and adapters. This is not a complete list, but it may help in
determining possible address conflicts. Symptoms of I/O address conflicts
vary widely. At one extreme, conflicts can prevent the computer from
booting. At the other extreme, conflicts can cause problems that do not
surface until a considerable amount of time has elapsed. When they do
surface, the problem can exhibit itself simply as strange behavior.
National Instruments has made every effort to select a software default base
I/O address that will work. However, because of the numerous different
interface boards available for use in the PC AT, it is not possible to select a
base I/O address that is guaranteed to work in all systems.