National Instruments NI-488.2M User manual

© Copyright 1994, 1996 National Instruments Corporation.
All Rights Reserved.
NI-488.2M™
User Manual for Windows NT
January 1996 Edition
Part Number 320646B-01

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© National Instruments Corp. v NI-488.2M UM for Windows NT
Contents
About This Manual ............................................................................................... xi
How to Use This Manual Set........................................................................... xi
Organization of This Manual........................................................................... xii
Conventions Used in This Manual................................................................... xiii
Related Documentation ................................................................................... xiv
Customer Communication ............................................................................... xiv
Chapter 1
Introduction.............................................................................................................. 1-1
GPIB Overview ............................................................................................... 1-1
Talkers, Listeners, and Controllers ................................................... 1-1
Controller-In-Charge and System Controller .................................... 1-1
GPIB Addressing............................................................................... 1-2
Sending Messages Across the GPIB ................................................. 1-2
Data Lines ........................................................................... 1-2
Handshake Lines................................................................. 1-3
Interface Management Lines............................................... 1-3
Setting Up and Configuring Your System......................................... 1-4
Controlling More Than One Board..................................... 1-5
Configuration Requirements ............................................................. 1-5
The NI-488.2M Software Elements................................................................. 1-6
NI-488.2M Driver and Driver Utilities ............................................. 1-6
DOS and 16-bit Windows Support Files........................................... 1-7
C Language Files............................................................................... 1-7
Sample Application Files .................................................................. 1-7
How the NI-488.2M Software Works with Windows NT............................... 1-8
Unloading and Reloading the NI-488.2M Driver ............................................ 1-9
Chapter 2
Application Examples........................................................................................... 2-1
Example 1: Basic Communication ................................................................. 2-2
Example 2: Clearing and Triggering Devices................................................. 2-4
Example 3: Asynchronous I/O........................................................................ 2-6
Example 4: End-of-String Mode..................................................................... 2-8
Example 5: Service Requests.......................................................................... 2-10
Example 6: Basic Communication with IEEE 488.2-Compliant Devices ..... 2-14
Example 7: Serial Polls Using NI-488.2 Routines ......................................... 2-16
Example 8: Parallel Polls ................................................................................ 2-18
Example 9: Non-Controller Example ............................................................. 2-20
Chapter 3
Developing Your Application............................................................................ 3-1
Choosing How to Access the NI-488.2M DLL ............................................... 3-1

Contents
NI-488.2M UM for Windows NT vi © National Instruments Corp.
Choosing Between NI-488 Functions and NI-488.2 Routines ........................ 3-1
Using NI-488 Functions: One Device for Each Board ..................... 3-2
NI-488 Device Functions .................................................... 3-2
NI-488 Board Functions ..................................................... 3-2
Using NI-488.2 Routines: Multiple Boards and/or
Multiple Devices ............................................................................... 3-3
Checking Status with Global Variables........................................................... 3-3
Status Word – ibsta ........................................................................... 3-3
Error Variable – iberr ........................................................................ 3-5
Count Variables – ibcnt and ibcntl .................................................... 3-5
Using ibic to Communicate with Devices ....................................................... 3-6
Writing Your NI-488 Application ................................................................... 3-6
Items to Include ................................................................................. 3-6
NI-488 Program Shell ....................................................................... 3-7
General Program Steps and Examples .............................................. 3-8
Step 1. Open a Device........................................................ 3-8
Step 2. Clear the Device..................................................... 3-8
Step 3. Configure the Device ............................................. 3-9
Step 4. Trigger the Device ................................................. 3-9
Step 5. Wait for the Measurement ..................................... 3-9
Step 6. Read the Measurement........................................... 3-10
Step 7. Process the Data..................................................... 3-10
Step 8. Place the Device Offline ........................................ 3-10
Writing Your NI-488.2 Application ................................................................ 3-11
Items to Include ................................................................................. 3-11
NI-488.2 Program Shell..................................................................... 3-12
General Program Steps and Examples .............................................. 3-13
Step 1. Initialization ........................................................... 3-13
Step 2. Find All Listeners .................................................. 3-13
Step 3. Identify the Instrument........................................... 3-13
Step 4. Initialize the Instrument ......................................... 3-14
Step 5. Configure the Instrument ....................................... 3-15
Step 6. Trigger the Instrument ........................................... 3-15
Step 7. Wait for the Measurement ..................................... 3-15
Step 8. Read the Measurement........................................... 3-16
Step 9. Process the Data..................................................... 3-16
Step 10. Place the Board Offline........................................ 3-17
Compiling, Linking and Running Your
GPIB Win32 Application................................................................................. 3-17
Microsoft Visual C/C++ .................................................................... 3-17
Direct Entry with C ........................................................................... 3-17
Microsoft Visual C/C++ ..................................................... 3-19
Borland C/C++.................................................................... 3-19
Running Existing DOS and Windows GPIB Applications.............................. 3-20

Contents
© National Instruments Corp. vii NI-488.2M UM for Windows NT
Chapter 4
Debugging Your Application............................................................................. 4-1
Running the Software Diagnostic Test ............................................................ 4-1
Presence Test of Driver ..................................................................... 4-1
Examining NT Devices to Verify the NI-488.2M
Installation........................................................................... 4-1
Examining the NT System Log Using the
Event Viewer....................................................................... 4-2
GPIB Cables Connected .................................................................... 4-2
Running GPIBInfo........................................................................................... 4-3
Debugging with the Global Status Variables................................................... 4-3
Debugging with ibic......................................................................................... 4-4
GPIB Error Codes ............................................................................................ 4-4
Configuration Errors ........................................................................................ 4-5
Timing Errors................................................................................................... 4-5
Communication Errors..................................................................................... 4-5
Repeat Addressing............................................................................. 4-5
Termination Method.......................................................................... 4-6
Common Questions ......................................................................................... 4-6
Chapter 5
ibic-Interface Bus Interactive Control Utility............................................ 5-1
Overview.......................................................................................................... 5-1
Example Using NI-488 Functions ................................................................... 5-1
ibic Syntax ....................................................................................................... 5-4
Number Syntax.................................................................................. 5-4
String Syntax ..................................................................................... 5-5
Address Syntax.................................................................................. 5-5
ibic Syntax for NI-488 Functions ...................................................... 5-5
ibic Syntax for NI-488.2 Routines..................................................... 5-8
Status Word ..................................................................................................... 5-9
Error Information............................................................................................. 5-9
Count................................................................................................................ 5-10
Common NI-488 Functions ............................................................................. 5-10
ibfind ................................................................................................. 5-10
ibdev .................................................................................................. 5-10
ibwrt................................................................................................... 5-12
ibrd..................................................................................................... 5-12
Common NI-488.2 Routines in ibic................................................................. 5-13
Set 488.2 ............................................................................................ 5-13
Send and SendList ............................................................................. 5-13
Receive .............................................................................................. 5-13
Auxiliary Functions ......................................................................................... 5-14
Set (udname or 488.2) ....................................................................... 5-14
Help (Display Help Information) ...................................................... 5-15
! (Repeat Previous Function)............................................................. 5-15
- (Turn OFF Display) and + (Turn ON Display)............................... 5-15
n* (Repeat Function n Times) ........................................................... 5-16

Contents
NI-488.2M UM for Windows NT viii © National Instruments Corp.
$ (Execute Indirect File)....................................................................5-16
Print (Display the ASCII String) ....................................................... 5-17
Chapter 6
GPIB Programming Techniques ..................................................................... 6-1
Termination of Data Transfers......................................................................... 6-1
High-Speed Data Transfers (HS488)............................................................... 6-2
Enabling HS488................................................................................. 6-2
System Configuration Effects on HS488 .......................................... 6-3
Waiting for GPIB Conditions .......................................................................... 6-3
Device-Level Calls and Bus Management....................................................... 6-3
Talker/Listener Applications ........................................................................... 6-4
Waiting for Messages from the Controller ........................................ 6-4
Using the Event Queue...................................................................... 6-4
Requesting Service ............................................................................ 6-5
Serial Polling ................................................................................................... 6-5
Service Requests from IEEE 488 Devices ........................................ 6-5
Service Requests from IEEE 488.2 Devices ..................................... 6-5
Automatic Serial Polling ................................................................... 6-6
Stuck SRQ State.................................................................. 6-6
Autopolling and Interrupts .................................................. 6-7
SRQ and Serial Polling with NI-488 Device Functions.................... 6-7
SRQ and Serial Polling with NI-488.2 Routines............................... 6-8
Example 1: Using FindRQS............................................... 6-9
Example 2: Using AllSpoll ................................................ 6-9
Parallel Polling................................................................................................. 6-10
Implementing a Parallel Poll ............................................................. 6-10
Parallel Polling with NI-488 Functions .............................. 6-10
Parallel Polling with NI-488.2 Routines............................. 6-11
Chapter 7
ibconf-Interface Bus Configuration Utility................................................. 7-1
Overview.......................................................................................................... 7-1
Starting and Exiting ibconf .............................................................................. 7-1
Board Configuration ........................................................................................ 7-2
Use this Board ................................................................................... 7-3
Bus Timing ........................................................................................ 7-4
Cable Length for High Speed ............................................................ 7-4
OK ..................................................................................................... 7-4
Cancel ................................................................................................ 7-4
Help ................................................................................................... 7-4
Software............................................................................................. 7-4
Base/IO Address................................................................................ 7-4
Interrupt Level................................................................................... 7-5
DMA Channel ................................................................................... 7-5
Use Demand Mode DMA ................................................................. 7-5

Contents
© National Instruments Corp. ix NI-488.2M UM for Windows NT
Expanded Board Configuration ....................................................................... 7-5
GPIB Primary Address ...................................................................... 7-6
GPIB Secondary Address .................................................................. 7-6
Terminate Read on EOS.................................................................... 7-6
Set EOI with EOS on Write............................................................... 7-7
8-bit EOS Compare ........................................................................... 7-7
Send EOI and end of Write ............................................................... 7-7
EOS Byte........................................................................................... 7-7
System Controller.............................................................................. 7-7
I/O Timeout ....................................................................................... 7-7
Parallel Poll Duration ........................................................................ 7-7
Enable Auto Serial Polling ................................................................ 7-7
Enable CIC Protocol.......................................................................... 7-8
Assert REN When SC ....................................................................... 7-8
Device Template Configuration....................................................................... 7-8
Name ................................................................................................. 7-9
Access Board..................................................................................... 7-9
GPIB Primary Address ...................................................................... 7-9
GPIB Secondary Address .................................................................. 7-9
Terminate Read on EOS.................................................................... 7-9
Set EOI with EOS on Write............................................................... 7-9
8-bit EOS Compare ........................................................................... 7-9
Send EOI at end of Write .................................................................. 7-9
EOS Byte........................................................................................... 7-10
I/O Timeout ....................................................................................... 7-10
Serial Poll Timeout............................................................................ 7-10
Repeat Addressing............................................................................. 7-10
Appendix A
Status Word Conditions ...................................................................................... A-1
Appendix B
Error Codes and Solutions................................................................................. B-1
Appendix C
Customer Communication................................................................................. C-1
Glossary........................................................................................................... Glossary-1
Index.......................................................................................................................Index-1

Contents
NI-488.2M UM for Windows NT x © National Instruments Corp.
Figures
Figure 1-1. GPIB Address Bits ..................................................................................... 1-2
Figure 1-2. Linear and Star System Configuration ....................................................... 1-4
Figure 1-3. Example of Multiboard System Setup ....................................................... 1-5
Figure 1-4. How the NI-488.2M Software Works with Windows NT ......................... 1-9
Figure 2-1. Program Flowchart for Example 1 ............................................................. 2-3
Figure 2-2. Program Flowchart for Example 2 ............................................................. 2-5
Figure 2-3. Program Flowchart for Example 3 ............................................................. 2-7
Figure 2-4. Program Flowchart for Example 4 ............................................................. 2-9
Figure 2-5. Program Flowchart for Example 5 ............................................................. 2-12
Figure 2-6. Program Flowchart for Example 6 ............................................................. 2-15
Figure 2-7. Program Flowchart for Example 7 ............................................................. 2-17
Figure 2-8. Program Flowchart for Example 8 ............................................................. 2-19
Figure 2-9. Program Flowchart for Example 9 ............................................................. 2-21
Figure 3-1. General Program Shell Using NI-488 Device Functions ........................... 3-7
Figure 3-2. General Program Shell Using NI-488.2 Routines ...................................... 3-12
Figure 7-1. Main Dialog Box in ibconf......................................................................... 7-2
Figure 7-2. Board Configuration for an AT-GPIB Interface Board.............................. 7-3
Figure 7-3. Expanded Board Configuration for an AT-GPIB Board ............................ 7-6
Figure 7-4. Device Template Configuration ................................................................. 7-8
Tables
Table 1-1. GPIB Handshake Lines ............................................................................... 1-3
Table 1-2. GPIB Interface Management Lines ............................................................. 1-3
Table 3-1. Status Word (ibsta) Layout .......................................................................... 3-4
Table 4-1. GPIB Error Codes ........................................................................................ 4-4
Table 5-1. Syntax for Device-Level NI-488 Functions in ibic ..................................... 5-6
Table 5-2. Syntax for Board-Level NI-488 Functions in ibic....................................... 5-7
Table 5-3. Syntax for NI-488.2 Routines in ibic........................................................... 5-8
Table 5-4. Auxiliary Functions in ibic .......................................................................... 5-14
Table A-1. Status Word Bits ......................................................................................... A-1
Table B-1. GPIB Error Codes ....................................................................................... B-1

© National Instruments Corp. xi NI-488.2M UM for Windows NT
About This Manual
This manual describes the features and functions of the NI-488.2M software for
Windows NT. The NI-488.2M software is meant to be used with the Microsoft
Windows NT operating system version 3.1 or higher, and the Microsoft Windows NT
Advanced Server version 3.1 or higher. This manual assumes that you are already
familiar with Windows NT.
How to Use This Manual Set
NI-488.2M
User Manual for
Windows NT
Application
Development
and Examples
Getting Started
Manual
Novice
Users
Installation and
Configuration
NI-488.2M Function
Reference Manual
for Windows NT
Experienced
Users
Function
and Routine
Descriptions
Use the getting started manual to install and configure your GPIB hardware and
NI-488.2M software for Windows NT.
Use the NI-488.2M User Manual for Windows NT to learn the basics of GPIB and how to
develop an application program. The user manual also contains debugging information
and detailed examples.
Use the NI-488.2M Function Reference Manual for Windows NT for specific NI-488
function and NI-488.2 routine information, such as format, parameters, and possible
errors.

About This Manual
NI-488.2M UM for Windows NT xii © National Instruments Corp.
Organization of This Manual
This manual is organized as follows:
• Chapter 1, Introduction, gives an overview of GPIB and the NI-488.2M software.
• Chapter 2, Application Examples, contains nine sample applications designed to
illustrate specific GPIB concepts and techniques that can help you write your own
applications. The description of each example includes the programmer's task, a
program flowchart, and numbered steps which correspond to the numbered blocks on
the flowchart.
• Chapter 3, Developing Your Application, explains how to develop a GPIB
application program using NI-488 functions and NI-488.2 routines.
• Chapter 4, Debugging Your Application, describes several ways to debug your
application program.
• Chapter 5, ibic–Interface Bus Interactive Control Utility, introduces you to ibic,
the interactive control program that you can use to communicate with GPIB devices
interactively.
• Chapter 6, GPIB Programming Techniques, describes techniques for using some
NI-488 functions and NI-488.2 routines in your application program.
• Chapter 7, ibconf–Interface Bus Configuration Utility, contains a description of
ibconf, the software configuration program you can use to configure the
NI-488.2M software.
• Appendix A, Status Word Conditions, gives a detailed description of the conditions
reported in the status word, ibsta.
• Appendix B, Error Codes and Solutions, lists a description of each error, some
conditions under which it might occur, and possible solutions.
• Appendix C, 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.
•TheIndex contains an alphabetical list of key terms and topics in this manual,
including the page where you can find each one.

About This Manual
© National Instruments Corp. xiii NI-488.2M UM for Windows NT
Conventions Used in This Manual
The following conventions are used in this manual.
bold Bold text denotes menu items and dialog box buttons or
options.
bold italic Bold italic text denotes a note, caution, or warning.
italic Italic text denotes emphasis, cross references, field names, or
an introduction to a key concept.
monospace Text in this font denotes text or characters that you enter from
the keyboard. Sections of code, programming examples, and
syntax examples also appear in this font. This font is also
used for the proper name of disk drives, paths, directories,
device names, variables, and for statements taken from
program code.
bold monospace Bold text in this font denotes the messages and responses that
the computer automatically prints to the screen.
italic monospace Italic text in this font denotes that you must supply the
appropriate words or values in the place of these items.
<> Angle brackets enclose the name of a key on the keyboard–for
example, <PageDown>.
- A hyphen between two or more key names enclosed in angle
brackets denotes that you should simultaneously press the
named keys–for example, <Control-C>.
IEEE 488 and IEEE 488 and IEEE 488.2 are used throughout this manual
IEEE 488.2 to refer to the ANSI/IEEE Standard 488.1-1987 and the
ANSI/IEEE Standard 488.2-1992, respectively, which define
the GPIB.
Abbreviations, acronyms, metric prefixes, mnemonics, symbols, and terms are listed in
the Glossary.

About This Manual
NI-488.2M UM for Windows NT xiv © National Instruments Corp.
Related Documentation
The following documents contain information that you may find helpful as you read this
manual:
• ANSI/IEEE Standard 488.1-1987, IEEE Standard Digital Interface for Programmable
Instrumentation
• ANSI/IEEE Standard 488.2-1992, IEEE Standard Codes, Formats, Protocols, and
Common Commands
•Microsoft Windows NT System Guide
•Microsoft Win 32 Software Development Kit for Windows NT: Tools
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 C, Customer Communication, at the end of this manual.

© National Instruments Corp. 1-1 NI-488.2M UM for Windows NT
Chapter 1
Introduction
This chapter gives an overview of GPIB and the NI-488.2M software.
GPIB Overview
The ANSI/IEEE Standard 488.1-1987, also known as GPIB (General Purpose Interface
Bus), describes a standard interface for communication between instruments and
controllers from various vendors. It contains information about electrical, mechanical,
and functional specifications. The GPIB is a digital, 8-bit parallel communications
interface with data transfer rates of 1 Mbytes/s and above, using a 3-wire handshake. The
bus supports one System Controller, usually a computer, and up to 14 additional
instruments. The ANSI/IEEE Standard 488.2-1987 extends IEEE 488.1 by defining a bus
communication protocol, a common set of data codes and formats, and a generic set of
common device commands.
Talkers, Listeners, and Controllers
GPIB devices can be Talkers, Listeners, or Controllers. A Talker sends out data
messages. Listeners receive data messages. The Controller, usually a computer, manages
the flow of information on the bus. It defines the communication links and sends GPIB
commands to devices.
Some devices are capable of playing more than one role. A digital voltmeter, for
example, can be a Talker and a Listener. If your personal computer has a National
Instruments GPIB interface board and NI-488.2M software installed, it can function as a
Talker, Listener, and Controller.
Controller-In-Charge and System Controller
You can have multiple Controllers on the GPIB, but only one Controller at a time can be
the active Controller, or Controller-In-Charge (CIC). The CIC can either be active or
inactive (Standby) Controller. Control can pass from the current CIC to an idle
Controller, but only the System Controller, usually a GPIB interface board, can make
itself the CIC.

Introduction Chapter 1
NI-488.2M UM for Windows NT 1-2 © National Instruments Corp.
GPIB Addressing
All GPIB devices and boards must be assigned a unique GPIB address. A GPIB address
is made up of two parts: a primary address and an optional secondary address.
The primary address is a number in the range 0 to 30. The GPIB Controller uses this
address to form a talk or listen address that is sent over the GPIB when communicating
with a device.
A talk address is formed by setting bit 6, the TA (Talk Active) bit of the GPIB address.
A listen address is formed by setting bit 5, the LA (Listen Active) bit of the GPIB
address. For example, if a device is at address 1, the Controller sends hex 41 (address 1
with bit 6 set) to make the device a Talker. Because the Controller is usually at primary
address 0, it sends hex 20 (address 0 with bit 5 set) to make itself a Listener. Figure 1-1
shows the configuration of the GPIB address bits.
Bit
Position 76543210
Meaning 0 TA LA GPIB Primary Address (range 0 to 30)
Figure 1-1. GPIB Address Bits
With some devices, you can use secondary addressing. A secondary address is a number
in the range hex 60 to hex 7E. When secondary addressing is in use, the Controller sends
the primary talk or listen address of the device followed by the secondary address of the
device.
Sending Messages Across the GPIB
Devices on the bus communicate by sending messages. Signals and lines transfer these
messages across the GPIB interface, which consists of 16 signal lines and eight ground
return (shield drain) lines. The 16 signal lines are discussed in the following sections.
Data Lines
Eight data lines, DIO1 through DIO8, carry both data and command messages.

Chapter 1 Introduction
© National Instruments Corp. 1-3 NI-488.2M UM for Windows NT
Handshake Lines
Three hardware handshake lines asynchronously control the transfer of message bytes
between devices. This process is a three-wire interlocked handshake, and it guarantees
that devices send and receive message bytes on the data lines without transmission error.
Table 1-1 summarizes the GPIB handshake lines.
Table 1-1. GPIB Handshake Lines
Line Description
NRFD (not ready for data) Listening device is ready/not ready to receive a message
byte. Also used by the Talker to signal high-speed GPIB
transfers.
NDAC (not data accepted) Listening device has/has not accepted a message byte.
DAV (data valid) Talking device indicates signals on data lines are stable
(valid) data.
Interface Management Lines
Five GPIB hardware lines manage the flow of information across the bus. Table 1-2
summarizes the GPIB interface management lines.
Table 1-2. GPIB Interface Management Lines
Line Description
ATN (attention) Controller drives ATN true when it sends commands and
false when it sends data messages.
IFC (interface clear) System Controller drives the IFC line to initialize the bus
and make itself CIC.
REN (remote enable) System Controller drives the REN line to place devices
in remote or local program mode.
SRQ (service request) Any device can drive the SRQ line to asynchronously
request service from the Controller.
EOI (end or identify) Talker uses the EOI line to mark the end of a data
message. Controller uses the EOI line when it conducts
a parallel poll.

Introduction Chapter 1
NI-488.2M UM for Windows NT 1-4 © National Instruments Corp.
Setting Up and Configuring Your System
Devices are usually connected with a cable assembly consisting of a shielded
24-conductor cable with both a plug and receptacle connector at each end. With this
design, you can link devices in a linear configuration, a star configuration, or a
combination of the two. Figure 1-2 shows the linear and star configurations.
Device B
Device C
Device A Linear
Configuration
Device D
Device C
Device B
Device A
Star
Configuration
Figure 1-2. Linear and Star System Configuration

Chapter 1 Introduction
© National Instruments Corp. 1-5 NI-488.2M UM for Windows NT
Controlling More Than One Board
The NI-488.2M driver can control up to 10 GPIB boards. Figure 1-3 shows an example
of a multiboard system configuration. gpib0 is the access board for the voltmeter, and
gpib1 is the access board for the plotter and printer. The control functions of the
devices automatically access their respective boards.
Printer
Plotter
Digital Voltmeter
gpib0
gpib1
One
GPIB
Another
GPIB
Figure 1-3. Example of Multiboard System Setup
Configuration Requirements
To achieve the high data transfer rate that the GPIB was designed for, you must limit the
physical distance between devices and the number of devices on the bus. The following
restrictions are typical:
• A maximum separation of four meters between any two devices and an average
separation of two meters over the entire bus.
• A maximum total cable length of 20 m.
• A maximum of 15 devices connected to each bus, with at least two-thirds powered
on.

Introduction Chapter 1
NI-488.2M UM for Windows NT 1-6 © National Instruments Corp.
For high-speed operation, the following restrictions apply:
• All devices in the system must be powered on.
• Cable lengths as short as possible up to a maximum of 15 m of cable for each
system.
• With at least one equivalent device load per meter of cable.
If you want to exceed these limitations, you can use bus extenders to increase the cable
length or expander to increase the number of device loads. Extenders and expanders are
available from National Instruments.
The following sections describe the NI-488.2M software, which controls the flow of
communication on the GPIB.
The NI-488.2M Software Elements
The following section highlights important elements of the NI-488.2M software for
Windows NT and describes the function of each element.
NI-488.2M Driver and Driver Utilities
The distribution disk contains the following driver and utility files:
•readme.txt is a documentation file that contains important information about the
NI-488.2M software and a description of any new features. Before you use the
software, read this file for the most recent information.
•gpibclsd.sys is the Windows NT kernel driver that implements the NI-488.2
device-level functions.
•gpibclsb.sys is the Windows NT kernel driver that implements the NI-488.2
board-level functions.
•gpib xxxx .sys (where xxxx represents a particular type of GPIB hardware–for
example, gpib-mc.sys for the MC-GPIB board or gpibatnt.sys for the
AT-GPIB/TNT board) is the Windows NT kernel driver that implements
hardware-specific features of the NI-488.2M software.
•gpib-32.dll is a 32-bit dynamic link library that acts as the interface between all
applications and the kernel mode GPIB driver.
•ibic.exe is an interactive control program that you use to communicate with the
GPIB devices interactively using NI-488.2 functions and routines. It helps you to
learn the NI-488.2 routines and to program your instrument or other GPIB devices.