HP 8712ET, 8712ES, 8714ET, 8714ES User Manual Supplement

Automating Measurements

HP 8712ET/ES and HP 8714ET/ES

RF Network Analyzers

User’s Guide Supplement

HP Part No. 08714-90014

Printed in USA

Print Date: October 1999

Supersedes: October 1998

Notice

Softkey

The information contained in this document is subject to change without notice. Hewlett-Packard makes no warranty of any kind with regard to this material, including but not limited to, the implied warranties of merchantability and ﬁtness for a particular purpose. Hewlett-Packard shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this material.

Key Conventions

This manual uses the following conventions:

FRONT PANEL KEY

analyzer (a “hardkey”).

: This indicates a “softkey”—a key whose label is determined by the instrument’s ﬁrmware, and is displayed on the right side of the instrument’s screen next to the eight unlabeled keys.

: This represents a key physically located on the

Acknowledgments

Excel™ is a product of Microsoft Corp. Lotus® 1-2-3®, and Lotus WordPro are U.S. registered trademarks of

Lotus Development Corporation. Microsoft is a U.S. registered trademark of Microsoft Corporation. QuickBasic™ is a product of Microsoft Corp.

Portions of the software include source code from the Info–ZIP group. This code is freely available on the Internet by anonymous ftp asftp.uu.net:/pub/archiving/zip/unzip51/.tar.Z, and from CompuServe asunz51.zip in the IBMPRO forum, library 10, (data compression).

iii

Hewlett-Packard Sales & Service Ofﬁces

UNITED STATES Instrument Support Center

Hewlett-Packard Company (800) 403-0801

EUROPEAN FIELD OPERATIONS Headquarters

Hewlett-Packard S.A. 150, Route du Nant-d’Avril 1217 Meyrin 2/ Geneva Switzerland (41 22) 780.8111

Great Britain Hewlett-Packard Ltd. Eskdale Road, Winnersh Triangle Wokingham, Berkshire RG41 5DZ England (44 734) 696622

INTERCON FIELD OPERATIONS Headquarters

Hewlett-Packard Company 3495 Deer Creek Rd. Palo Alto, CA 94304-1316 USA (415) 857-5027

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Australia Hewlett-Packard Australia Ltd. 31-41 Joseph Street Blackburn, Victoria 3130 (61 3) 895-2895

Germany Hewlett-Packard GmbH Hewlett-Packard Strasse 61352 Bad Homburg v.d.H Germany (49 6172) 16-0

Canada Hewlett-Packard (Canada) Ltd. 17500 South Service Road Trans-Canada Highway Kirkland, Quebec H9J 2X8 Canada (514) 697-4232

Japan Hewlett-Packard Japan, Ltd. Measurement Assistance Center 9-1, Takakura-Cho, Hachioji-Shi Tokyo 192-8510, Japan TEL (81) -426-56-7832 FAX (81) -426-56-7840

China China Hewlett-Packard Co. 38 Bei San Huan X1 Road Shuang Yu Shu Hai Dian District Beijing, China (86 1) 256-6888

Singapore Hewlett-Packard Singapore (Pte.) Ltd. 150 Beach Road #29-00 Gateway West Singapore 0718 (65) 291-9088

Taiwan Hewlett-Packard Taiwan 8th Floor, H-P Building 337 Fu Hsing North Road Taipei, Taiwan (886 2) 712-0404

HP 8712ET/ES and HP 8714ET/ES Network Analyzer Documentation Map

The CDROM provides the contents of all of the documents listed below.

The User’s Guide shows how to make measurements, explains commonly-used features, and tells you how to get the most performance from the analyzer.

The LAN Interface User’s Guide Supplement shows how to use a local area network (LAN) for programming and remote operation of the analyzer.

The Automating Measurements User’s Guide Supplement provides information on how to conﬁgure and control test systems for automation of test processes.

The Programmer’s Guide provides programming information including HP-IB and SCPI command references, as well as short programming examples.

The Example Programs Guide provides a tutorial introduction using BASIC programming examples to demonstrate the remote operation of the analyzer

The Service Guide provides the information needed to adjust, troubleshoot, repair, and verify analyzer conformance to published speciﬁcations.

The HP Instrument BASIC User’s Handbook describes programming and interfacing techniques using HP Instrument BASIC, and includes a language reference.

The HP Instrument BASIC User’s Handbook Supplement shows how to use HP Instrument BASIC to program the analyzer.

The Option 100 Fault Location and Structural Return Loss Measurements User’s Guide Supplement provides theory and measurement examples for making fault location and SRL measurements. (Shipped only with Option 100 analyzers.)

The CATV Quick Start Guide provides abbreviated instructions for testing the quality of coaxial cables. (Shipped only with Option 100 analyzers.)

The Cellular Antenna Quick Start Guide provides abbreviated instructions for verifying the performance of cellular antenna systems. (Shipped only with Option 100 analyzers.)

Contents

1. Introduction

Automating Measurements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

2. Conﬁguring Your Test System

Measurement System Conﬁgurations and Considerations. . . . . . . . . . . . . . . . . . . . . . 2-2

Stand-Alone Network Analyzers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

External Computer Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

Expandability and Large Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7

Throughput Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8

Selecting a Measurement Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9

Stand-Alone Operation using IBASIC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9

Computer-Controlled HP-IB Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9

Computer-Controlled LAN Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10

Using IBASIC and External Control Together. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10

Selecting a Programming Language. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

HP BASIC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

IBASIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11

HP VEE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12

Microsoft® QuickBasic™ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12

C and C++ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12

VXI plug&play Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13

Example Programs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13

3. Operator Interaction

Prompting the Operator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4

Using Graphics to Create On-Screen Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

User-Deﬁned BEGIN Key Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

Loading a User BEGIN Program. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10

Modifying a User BEGIN Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10

Using a Switch with User BEGIN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11

Using a Barcode Reader for Data Entry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13

Using an External Keyboard for Data Entry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14

Using the Analyzer's Title Feature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15

Hot Keys on External Keyboard for Common Functions . . . . . . . . . . . . . . . . . . . . . . 3-16

User-Deﬁned TTL Input/Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-18

Using a Foot or Hand Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-19

vii

Contents

Limit-Test Pass/Fail TTL Input/Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-21

Analyzer Port Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-22

Output for External VGA-Compatible Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-24

4. Measurement Setup and Control with Fast Recall

Using Fast Recall with the Front Panel or a Keyboard . . . . . . . . . . . . . . . . . . . . . . . . .4-3

Using Fast Recall with a Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-5

5. Automated Measurement Setup and Control

Setting the Instrument State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-4

Recalling Instrument States from Disk. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-4

Using Learn Strings to Save and Recall Instrument States . . . . . . . . . . . . . . . . . . .5-6

SCPI Commands that Modify a Single Parameter. . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-7

Fast Iterative Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-8

Responsive Communication using SRQs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-10

Using Both of the Analyzer's Measurement Channels . . . . . . . . . . . . . . . . . . . . . . . .5-11

Using Single Sweep to Measure and View All Four S-Parameters. . . . . . . . . . . . . . .5-12

AUTOST ﬁles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-15

6. Controlling Peripherals

Using the Parallel Port. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-3

Writing to the Parallel Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-6

Reading from the Parallel Port. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-9

Hardcopy Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-10

Using the Serial Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-11

7. Displaying Measurement Results

Graticule On/Off. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-3

Limit Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-4

To turn limit lines on or off. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-4

To turn the fail icon on or off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-4

To turn the pass/fail text on or off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-4

To move the position of the pass/fail indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-5

Customized X-axis Annotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-6

To turn on user-deﬁned X-axis annotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-6

To specify your start and stop values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-6

viii

Contents

To specify a custom sufﬁx. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6

To turn the X-axis annotation on or off. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7

Customized Measurement-Channel Annotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8

To turn on user-deﬁned measurement-channel annotation. . . . . . . . . . . . . . . . . . . . 7-8

To specify the string to be displayed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8

To restore default measurement-channel annotation . . . . . . . . . . . . . . . . . . . . . . . . 7-8

To turn measurement-channel annotation on or off. . . . . . . . . . . . . . . . . . . . . . . . . . 7-9

Markers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-10

Title and Clock. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-12

8. Saving Measurement Results

Querying Measurement Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3

Saving the Measurement to Disk — Save ASCII. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4

Saving the Measurement to Disk — Save Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5

Querying Marker Searches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6

Saving Measurement Results to Disk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-7

Using Hardcopy Features to Print or Plot Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8

Faster Hardcopies using a PCL5 Printer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9

Customizing Page Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9

Custom Data Sheets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-12

Statistical Process Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-14

Transferring Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-15

Contents

1 Introduction

1-1

Introduction

Automating Measurements

An automated measurement system is one where a computer performs some of the tasks that you would normally have to do manually.

The information in this book will help you learn how to automate your measurement system. Several features of the instrument that are useful for automation are explained.

NOTE The information in this book assumes that you are familiar with the

information provided in the Programmer's Guide, the HP Instrument

BASIC User's Handbook, and the HP Instrument BASIC User’s Handbook Supplement that were supplied with your analyzer.

This book explains how to control your analyzer using internal IBASIC or with an external computer connected via HP-IB. The analyzer’s internal CPU running IBASIC programs acts as a complete system controller residing inside your analyzer. You have the additional capability of controlling the analyzer over a LAN. Refer to the LAN Interface User’s Guide Supplement (supplied with the analyzer) for information.

Some of the analyzer features that support automation are built-in and operate solely on the analyzer; limit testing is one example of a built-in automation feature. Other features can be executed by programs running internally under IBASIC or on an external computer.

NOTE Example programs can be found in the following four locations:

• Web site http://www.hp.com or http://www.agilent.com. Use the search function to ﬁnd Web pages related to 8712 example programs.

• Example Programs Disk, HP 8712ET/ES and HP 8714ET/ES (DOS format): HP part number 08714-10003

• Example Programs Disk, HP 8712ET/ES and HP 8714ET/ES (LIF format): HP part number 08714-10004

• Example Programs Guide, HP 8712ET/ES and HP 8714ET/ES: HP part number 08714-90016

1-2 Automating Measurements

Introduction

Automating Measurements

Use of automation improves the productivity of a measurement system by increasing the system's throughput. Throughput is typically measured as the amount of units or components produced over a particular period of time. Throughput can be increased by minimizing the time for the following factors:

• device handling time

• operator interaction time

• measurement speed

• data transfer speed

• computation speed (when applicable) Be sure to consider all of these factors when choosing and setting up an

automated system. Automating your measurements can help ensure consistent quality on a

production line. An automated system can perform repetitive tasks quickly and consistently. Automation can be used to direct you through a sequence of tests, to set instrument parameters, and to send prompts with helpful directions or diagrams. Automation is also used to collect data, to monitor production line performance, and to archive and analyze data.

Using a consistent, documented production process, while monitoring product quality, are important attributes of modern production and quality standards such as ISO-9000. These attributes are best achieved with an automated system.

NOTE Hewlett-Packard offers professional consulting services to help increase

your manufacturing productivity. A complete test process analysis can be performed by HP system engineers, who will work with your factory management, engineering, and production groups to evaluate various automation solutions. F or more information contact the nearest HP sales ofﬁce. Refer to the front of this book for a table of sales and service ofﬁces.

Automating Measurements 1-3

Introduction

Automating Measurements

1-4 Automating Measurements

2 Conﬁguring Your Test System

2-1

Conﬁguring Your Test System

Measurement System Conﬁgurations and Considerations

When conﬁguring your test system, there are many things to consider, such as:

• how many test stations do you need now?

• how many test stations will be needed in the future?

• how much space is available at each test station?

• what type of testing will be done?

• how will the measurements be controlled?

• how will the data be analyzed and archived?

• what level of throughput is required? After answering these questions, you should decide which of the

following conﬁgurations best meets your needs.

2-2 Automating Measurements

Conﬁguring Your Test System

Measurement System Conﬁgurations and Considerations

Stand-Alone Network Analyzers

In the stand-alone conﬁguration, you can either take advantage of the operator-initiated automation features, or you can use the internal CPU and IBASIC programs to further automate your measurements.

Stand-Alone Analyzer under Operator Control

In this conﬁguration, the measurement is controlled directly by the operator, with very little automation. No computer or IBASIC control is used, however the fast-recall feature may be used to quickly change between different instrument states. This conﬁguration is well suited for simple pass/fail testing using the built-in limit-testing features. Conﬁgure your system as a stand-alone analyzer if you would like to

• simplify test-system conﬁguration

• maintain full control by operators

• minimize test-development time

Stand-Alone Analyzer under IBASIC Control

In this conﬁguration, the measurement is controlled by an IBASIC program running inside the analyzer. With IBASIC, the measurement setup and control can be highly automated, reducing the burden on the operator. Since the measurement is under programmatic control, data can be collected and analyzed in order to monitor your process and quality. IBASIC's keystroke recording lets you construct programs quickly, without needing to refer to the programming documentation. Using AUTOST ﬁles, the analyzer will load and run your program when power is turned on.

Since no external computer is required, there are fewer system components to purchase, maintain, connect, and synchronize.

Automating Measurements 2-3

Conﬁguring Your Test System

Measurement System Conﬁgurations and Considerations

Conﬁgure your system as a stand-alone instrument with IBASIC if you would like to

• simplify test-system conﬁguration

• minimize the space required for a system

• simplify programming with keystroke recording

• use key macros

• automate measurement setup and control

• simplify measurements

• collect data

• run application programs on the analyzer

Figure 2-1 depicts a stand-alone network analyzer running IBASIC.

Figure 2-1 Stand-Alone Network Analyzer Running IBASIC

BEGIN

2-4 Automating Measurements

Conﬁguring Your Test System

Measurement System Conﬁgurations and Considerations

External Computer Control

You can use an external computer to control your analyzer or test system by using the LAN or HP-IB interface on your analyzer. Additionally, you can use an external computer in conjunction with the analyzer’s internal CPU running IBASIC for optimum throughput. (F or more information on using the LAN interface, refer to The LAN Interface User’s Guide Supplement.)

External Computer Alone

In this conﬁguration, the measurement is controlled by a computer external to the analyzer, using the LAN or the HP-IB interface. The measurement setup and control can be highly automated and designed for optimum throughput. Data can be automatically collected and analyzed in order to monitor quality and processes. You can connect one or more analyzers to each computer. Since the computer can be connected to other computers via a Local Area Network (LAN), measurement statistics can be easily tracked and archived using computer applications.

Conﬁgure your system as an analyzer controlled by an external computer if you would like to

• centralize automation and application programs

• develop a more sophisticated data collection system

• add networking capability

Figure 2-2 Network Analyzer Controlled by a Computer

Automating Measurements 2-5

Conﬁguring Your Test System

Measurement System Conﬁgurations and Considerations

External Computer in Conjunction with IBASIC

In this conﬁguration, the measurement is controlled by an IBASIC program running inside the analyzer. IBASIC can provide high-speed measurement control and data collection, and save the results in program memory or on a disk. The external computer then communicates with IBASIC, and collects the measurement results at some deﬁned interval. This conﬁguration can result in higher throughput, especially if the measurement setup and control is complex. Conﬁgure your system as an analyzer with IBASIC and an external computer if you would like to

• centralize automation and application programs

• develop a more sophisticated data collection system

• add networking capability

• add local-automation capability

Figure 2-3 Network Analyzer Running IBASIC, Controlled by a Computer

2-6 Automating Measurements

Conﬁguring Your Test System

HP-IB

Expandability and Large Systems

You can connect up to 10 analyzers to a single computer without compromising maximum HP-IB bus speed. The IEEE-488 standard states that the bus can achieve a data rate of 500 KBytes per second for buses up to 20 meters in length, with up to 10 devices (one device per 2 meters of cable).

IEEE-488 provides for 31 unique addresses (0 through 30), however it restricts the number of devices on the bus to 15. Due to this restriction, you may need to add more computers as you add more analyzers. Set each analyzer's address via the menu.

With your analyzer’s LAN feature, you can overcome the physical limitations of HP-IB cabling and create large systems with hundreds of analyzers. 10-BaseT LAN provides a theoretical bandwidth of close to 1 MByte/second, although in practice, throughput will be slower. See The LAN Interface User’s Guide Supplement for more information.

SYSTEM OPTIONS

Automating Measurements 2-7

Conﬁguring Your Test System

Throughput Considerations

When considering the throughput of the system conﬁguration, contributing factors are

• device handling time

• operator interaction time

• measurement speed

• data transfer speed

• computation speed (when applicable) For more information, refer to Improving Throughput in Network

Analyzer Applications, HP application note number AN 1287-5 (or literature number 5966-3317E).

2-8 Automating Measurements

Conﬁguring Your Test System

Selecting a Measurement Controller

There are three standard conﬁgurations that you can use to control the analyzer:

• stand-alone operation using IBASIC

• computer-controlled HP-IB operation

• computer-controlled LAN operation

Stand-Alone Operation using IBASIC

IBASIC, in effect, puts a controller inside your analyzer and eliminates the need for an external computer. IBASIC controls the analyzer by sending SCPI commands to address 800 (OUTPUT 800;”Command”), or by using high-speed built-in subprograms. Since IBASIC shares CPU time with the analyzer, it may cause some degradation in measurement throughput if your program performs intensive computations. However, for most applications, it provides excellent performance and convenience. Refer to the HP Instrument BASIC User's Handbook and HP Instrument BASIC User’s Handbook Supplement for more information.

Computer-Controlled HP-IB Operation

An external computer can be used to control the analyzer. It can be a personal computer (PC) or a dedicated HP BASIC controller. The external computer sends standard SCPI commands to address 716 (default) (OUTPUT 716;”Command”) to control the analyzer . Refer to the Programmer's Guide for more information.

You can use one computer to control several analyzers (see “Expandability and Large Systems” earlier in this chapter). However , if a large number of SCPI commands are required per measurement, throughput may be degraded. Typical limits are 3 to 10 analyzers per computer.

Automating Measurements 2-9

Conﬁguring Your Test System

Selecting a Measurement Controller

Computer-Controlled LAN Operation

An external computer can send SCPI commands via the LAN using a telnet connection. Refer to The LAN Interface User’s Guide Supplement for more information.

You can use one computer to control several analyzers. Performance will typically be limited by the computer's speed, which in turn will limit the number of analyzers per computer.

Using IBASIC and External Control Together

The analyzer can be controlled by commands from an external computer, internal IBASIC, or from both at the same time, as long as certain precautions are observed. Things to consider:

1. If both the analyzer and the computer send SCPI commands at the same time, the analyzer may not ﬁnish the IBASIC command before executing the computer's command, or vice-versa. The programmer must ensure that SCPI commands executed by IBASIC do not overlap with SCPI commands sent from an external computer, otherwise the system may lock up. Synchronization between the analyzer and the external computer must be ensured. See “Synchronizing IBASIC with an External Controller” in HP Instrument BASIC User’s Handbook Supplement for additional information.

2. Both IBASIC (SelectCode 8) and the external computer (LAN or SelectCode 7) share the same HP-IB status model (the same analyzer status bits go to each). Be careful sending commands which affect status reporting, such as *CLS, STAT:PRES, *RST, etc.

2-10 Automating Measurements

Conﬁguring Your Test System

Selecting a Programming Language

HP BASIC

HP BASIC has long been a favorite programming language for instrument control. It features an extensive list of keywords, and powerful OUTPUT and ENTER formatting, making it easy to perform common tasks. This generally results in very high programming productivity. HP BASIC runs on HP series 700 workstations and series 300 instrument controllers.

IBASIC

IBASIC is a version of BASIC that runs inside of the network analyzer. IBASIC is a sub-set of HP's BASIC . It has roughly the same keywords as

HP BASIC 4.0. With very little effort, you can design your program so that it will run either inside the analyzer or on a computer with no modiﬁcation.

The IBASIC program runs concurrently with normal instrument measurement processing. Since IBASIC has direct access to the analyzer's measurement arrays, it can read them and write to them very quickly, eliminating the need to use SCPI commands. Using IBASIC's keystroke recording, you can write a large portion of your instrument control program by pressing the keys on the analyzer's front panel. IBASIC can be used in a stand-alone instrument, or in conjunction with an external computer.

For more information on IBASIC, refer to the HP Instrument BASIC

User's Handbook and HP Instrument BASIC User’s Handbook Supplement that were shipped with your analyzer.

Automating Measurements 2-11

Conﬁguring Your Test System

Selecting a Programming Language

HP VEE

HP VEE is a powerful application which lets you graphically create programs to control your instrument. VEE automatically handles the programming details so you can focus on higher level tasks. It also contains statistical functions which you can use to monitor your production process.

VEE runs on PCs as well as HP-UX and Sun Workstations. VEE can be used in conjunction with a VEE instrument driver. The VEE

instrument driver presents a picture of the instrument's front panel on the computer display. Using the mouse, you can click on the front panel keys to control the instrument, similar to IBASIC keystroke recording.

For information on VEE, including literature and preview disks, please call the nearest HP instrument support center, or sales or service ofﬁce. Refer to the front of this book for a table of sales and service ofﬁces.

Microsoft® QuickBasic™

QuickBasic has been a popular programming language since it runs on PCs. It does not offer a rich keyword set as does HP BASIC, and is not optimized for instrument control. To control the analyzer via HP-IB, an HP-IB card and driver library must be installed in the computer. The driver library will provide subroutines such as IOOUTPUT and IOENTER which let you control your analyzer.

C and C++

If you are using C or C++, you will need a driver library to use your HP-IB card. HP offers a library called Standard Instrument Control Library (SICL). SICL is available for PCs running Microsoft Windows® and using HP's HP-IB card. SICL is also available on HP series 700 UNIX workstations.

For LAN communication with your analyzer, C or C++ is often used. Multi-threaded programs can be created to allow easy and precise control of many analyzers operating asynchronously. This approach maximizes speed and throughput.

2-12 Automating Measurements

Conﬁguring Your Test System

Selecting a Programming Language

VXI plug&play Driver

Your analyzer is VXI plug&play compliant. VXI plug&play drivers provide a high level control interface for the analyzer, thereby reducing the level of instrument-speciﬁc knowledge required to program the analyzer. The driver for the HP 8712ET/ES and HP 8714 ET/ES functions in Win95, Win98, and WinNT (3.51 or higher) and was designed for the following programming platforms:

• Microsoft Visual C++ version 4.0 or higher

• Microsoft Visual BASIC version 5.0 or higher

• Borland C++ version 4.5 or higher

• HP VEE version 3.2 or higher

• National Instruments Lab Window/CVI version 4.0.1 or higher

• National Instrument LabVIEW version 5.00 or higher The free VXI plug&play driver for your analyzer should be available

soon on the Web at:

http://www.tmo.hp.com/tmo/software/English/comptest_VXI_drivers.html

http://www.hp.com/go/ena

Example Programs

The Programmer's Guide contains detailed information on controlling the analyzer via HP-IB. The Example Programs Guide includes several example programs written in HP BASIC and in IBASIC.

The HP Instrument BASIC User's Handbook and HP Instrument BASIC User’s Handbook Supplement contain detailed information on how to control the analyzer using IBASIC.

The LAN Interface User’s Guide Supplement contains detailed information on controlling the analyzer via LAN, including example programs.

Automating Measurements 2-13

Conﬁguring Your Test System

Selecting a Programming Language

2-14 Automating Measurements

3 Operator Interaction

3-1

Operator Interaction

Many tests are performed by technicians, operators, or testers who interact with the measurement system. When designing the automation system, it is important that the system allow operators to perform the measurement tasks quickly and consistently. The system must also be easy to learn and easy to use, providing the user with instructions and feedback.

The analyzer provides many features to satisfy these requirements. The features include

• user-deﬁned pop-up messages to prompt the operator

• on-screen graphics to create custom diagrams

• user-deﬁned measurement channel and frequency annotation

• ability to deﬁne the key menu with frequently-used custom softkeys

• IBASIC display window; conﬁgurable as full or split

• IBASIC DISP line and INPUT line

• data entry using a barcode reader

• data entry using an external keyboard

• hot keys on external keyboard for common functions

• operator control of measurements using a foot or hand switch

• beeper with adjustable volume and pitch

• limit test pass/fail TTL output

• user-deﬁned TTL input/output

• output for external VGA-compatible color monitor

The following sections explain how to use these features, and show several examples.

BEGIN

3-2 Automating Measurements

+ 86 hidden pages

HP 8712ET, 8712ES, 8714ET, 8714ES User Manual Supplement

Specifications and Main Features

Frequently Asked Questions

User Manual

1 Introduction

Automating Measurements

Stand-Alone Network Analyzers

External Computer Control

Expandability and Large Systems

Throughput Considerations

Selecting a Measurement Controller

Stand-Alone Operation using IBASIC

Computer-Controlled HP-IB Operation

Computer-Controlled LAN Operation

Using IBASIC and External Control Together

Selecting a Programming Language

HP BASIC

IBASIC

HP VEE

Microsoft® QuickBasic™

C and C++

VXI plug&play Driver

Example Programs

3 Operator Interaction