Wiltron 360B Owner's manual

490 JARVIS DRIVE
MORGAN HILL, CA 95037-2809
MODEL
360B
VECTOR NETWORK ANALYZER
GPIB PROGRAMMING MANUAL
Software Version 4.03
P/N: 10410-00113
REVISION: B
PRINTED: SEPTEMBER 1993
COPYRIGHT 1991 WILTRON CO.

WARRANTY
The WILTRON product(s) listed on the title page is (are) warranted against defects in materials
and workmanship for one year from the date of shipment, except for YIG-tuned oscillators, which
are warranted for two years.
WILTRON’s obligation covers repairing or replacing products which prove to be defective during the
warranty period. Buyers shall prepay transportation charges for equipment returned to WILTRON
for warranty repairs. Obligation is limited to the original purchaser. WILTRON is not liable for
consequential damages.
LIMITATION OF WARRANTY
The foregoing warranty does not apply to WILTRON connectors that have failed due to normal
wear. Also, the warranty does not apply to defects resulting from improper or inadequate
maintenance by the Buyer, unauthorized modification or misuse, or operation outside of the
environmental specifications of the product. No other warranty is expressed or implied, and the
remedies provided herein are the Buyer’s sole and exclusive remedies.
NOTICE
WILTRON Company has prepared this manual for use by WILTRON Company personnel and
customers as a guide for the proper installation, operation and maintenance of WILTRON Company
equipment and computer programs. The drawings, specifications, and information contained herein
are the property of WILTRON Company, and any unauthorized use or disclosure of these drawings,
specifications, and information is prohibited; they shall not be reproduced, copied, or used in whole
or in part as the basis for manufacture or sale of the equipment or software programs without the
prior written consent of WILTRON Company.

Table
of Contents
Tab / Chapter Title
1 General GPIB Information
This chapter describes the manual and contains a brief de-
scription of the GPIB hardware and the GPIB data trans-
fer and control functions. It also describes the 360B VNA
GPIB interface function subset capability and response to
IEEE-488 interface function messages.
2 Introduction to 360B GPIB Programming
This chapter provides a brief introduction to GPIB pro-
gramming techniques and describes procedures to be used
when preparing GPIB programs for the 360B VNA. It in-
cludes information about 360B GPIB command syntax, pro-
gramming tips and example programs.
3 Front Panel Functions
This chapter describes the 360B GPIB commands that con-
trol the basic test and measurement functions associated
with the 360B front panel controls and menus. The com-
mand descriptions are grouped by control function, for ex-
ample: Data Entry Commands, Hard Copy Commands, etc.
4 Calibration Functions
This chapter describes the 360B GPIB commands used to
perform system calibration functions.
5 Advanced/Unique Functions
This chapter describes the 360B GPIB commands that pro-
duce operations that are unique to the GPIB mode of opera-
tion. Example commands included are: Data Transfer com-
mands, Group Execute commands, etc. As in the previous
sections, the command descriptions are grouped by control
function.
360B GPIB PM i

6 Supplements
This tab section includes application notes pertaining to
360B GPIB programming.
7 GPIB Command Function Index
This index lists the GPIB commands for the 360B by func-
tion. The paragraph number and page number for each of
28 GPIB command function categories are referenced.
8 GPIB Quick Reference Guide
This Quick Reference Guide is an alphabetical list of the
GPIB commands for the 360B. The listing for each com-
mand includes a brief description of the command function
and attributes (such as associated parameters). This docu-
ment is also an alphabetical index to the 360B Vector Net-
work Analyzer GPIB Programming Manual. The listing for
each command includes a reference to the paragraph in
the programming manual that includes the complete de-
scription of the command.
Appendix A Installation and Configuration Instructions
for the National Instruments GPIB Card
This appendix provides installation and configuration in-
structions for the National Instruments GPIB-PCII/IIA
card and software.
Appendix B “OCF” Command Binary String Data
This appendix contains an index listing of the data string
that is returned in response to sending the OCF command.
Contents (Continued)
Tab / Chapter Title
Microsoft Cis a registered trademark of Microsoft Corporation.
ii 360B GPIB PM

Table of Contents
1-1 INTRODUCTION . . . . . . . . . . . . . . . . . . 1-3
Relationship of This Manual to Other
360B VNAManuals . . . . . . . . . . . . . . . . 1-3
How to Use This Manual . . . . . . . . . . . . . . 1-4
Command Categories Used in This Manual . . . . 1-5
1-2 DESCRIPTION OF THE IEEE-488 (IEC-625)
INTERFACE BUS . . . . . . . . . . . . . . . . . . 1-5
IEEE-488 Hardware Interface . . . . . . . . . . . . 1-7
Data Byte Transfer Control Bus Description . . . . 1-7
IEEE-488 Interface Functions and Protocols . . . . 1-9
IEEE-488 Message Types . . . . . . . . . . . . . . 1-10
1-3 360B VNAGPIB OPERATION . . . . . . . . . . . 1-12
Setting Default GPIB Operating Parameters . . . 1-12
Response to GPIB Interface Function Messages . . 1-12
360B VNA Response To GPIB Error Conditions . . 1-12
Chapter 1
General GPIB Informatio
n

Chapter 1
General GPIB
Information
1-1 INTRODUCTION This manual describes remote operation of the WILTRON 360B Vector
Network Analyzer using IEEE-488 Interface Function Messages and
360B GPIB Commands (i.e., Product Specific Commands).
Included is a description of the IEEE-488 General Purpose Interface
Bus (GPIB) hardware and the bus data transfer and control functions.
Also included is a brief introduction to GPIB programming, including
considerations for preparing GPIB programs for the 360B Vector Net-
work Analyzer (VNA). All 360B VNAGPIB commands currently used
are listed and described.
The programming information and examples presented in this manual
assume that the external computer/controller used with the 360B is
IBM-XT, AT, or PS/2 compatible, or a Hewlett Packard 9000 or Vectra
series computer. The computer/controller must be equipped with an
IEEE-488 GPIB interface (built-in or add-in peripheral card) with ap-
propriate driver software. The National Instruments GPIB-PCII/IIA
IEEE-488 interface card is assumed for all IBM compatible computers.
(Information and instructions for installing the National Instruments
GPIB-PCII/IIAIEEE-488 interface card is contained in Appendix Aat
the rear of this manual.)
The information about the IEEE-488 interface bus presented in this
manual is general in nature. For complete and specific information, re-
fer to the ANSI/IEEE Std 488-1978 document entitled “IEEE Stand-
ard Digital Interface for Programmable Instrumentation.” This docu-
ment precisely defines the set of dedicated hardware signal lines,
interface functions, protocols, and messages for the interface bus.
In several chapters, especially Chapter 5, computer programs that il-
lustrate use of various commands are used. Some of these programs
can be obtained on diskette by contacting WILTRON Customer Serv-
ice at 408-778-2000.
Relationship
of This Man-
ual to Other
360B VNA
Manuals
This manual is intended to be used in conjunction
with the 360B Vector Network Analyzer System Op-
eration Manual. Refer to that manual for general in-
formation about the 360B VNA, including
equipment set up and manual mode operating in-
structions. Chapter 1 of that manual lists and de-
360B GPIB PM 1-3

scribes all 360B VNA documentation set manuals,
including test set and software manuals.
How to Use
This Manual Only information pertinent to 360B VNAGPIB pro- gramming is provided in this manual. Familiarity
with manual (front panel) operation of the 360B
VNAis assumed. System operating details are
given in this manual only if they are unique to the
GPIB operating mode, or are different than when op-
erated in the normal manual mode.
This chapter describes the manual and contains a
brief description of the GPIB hardware and the
GPIB data transfer and control functions. If you are
already familiar with this material, this section
may be skipped. The remainder of the manual is or-
ganized as follows:
Chapter 2 — Introduction to GPIB Programming
for the 360B VNA — contains a brief introduction to
GPIB programming techniques and describes proce-
dures to be used when preparing GPIB programs
for the 360B VNA. If you are already familiar with
this material, this section may be skipped.
Chapters 3, 4, and 5— describe the 360B GPIB com-
mands used for Basic Front Panel Functions, Cali-
bration Functions and Advanced
Programming/GPIB Unique Functions, respectively.
The programming information and tables contain-
ing the command descriptions are grouped by func-
tion in these sections. Use this information as a
tutorial and for reference when preparing programs.
The Functional Index Of Commands — lists the
360B GPIB commands by function and references
the paragraph and page number where the descrip-
tions for that group of commands are located in
Chapters 3 thru 5.
360B GPIB Quick Reference Guide — This sepa-
rately bound document is located behind the last
section tab of this manual. It lists the 360B GPIB
commands alphabetically and references the loca-
tion in Chapters 3 thru 5 of this manual where infor-
mation for each command is located. The listing in
this guide for each command includes a brief de-
scription of the command function and associated
parameters. Use this guide as a quick reference
when preparing programs.
GENERAL GPIB
INFORMATION INTRODUCTION
1-4 360B GPIB PM

Command
Categories
Used in This
Manual
The 360B VNAGPIB interface responds to more
than 400 commands to implement the set of 360B
network analyzer functions. For descriptive pur-
poses, these commands are organized into the fol-
lowing functional classifications:
Basic Front Panel Functions
These commands produce basic 360B VNA measure-
ment operations identical to those produced by the
corresponding key functions on the 360B front
panel. These commands are described in Chapter 3.
Calibration Functions
The set of calibration commands can be used to set
up the calibration parameters under program con-
trol and to guide an operator through the 360B VNA
calibration process. These commands are described
in Chapter 4.
GPIB Unique Functions
These commands produce 360B VNA operations
that are unique to the GPIB mode of operation or
are operations that are best done using computer
control of the system. They are described in
Chapter 5.
1-2 DESCRIPTION OF THE
IEEE-488 (IEC-625)
INTERFACE BUS
The IEEE-488 General Purpose Interface Bus (GPIB) is an instrumen-
tation interface for integrating instruments, computers, and other con-
trollers into systems. The bus uses 16 signal lines to effect transfer of
data and commands to all instruments connected on the bus.
No more than 15 instruments may be connected to the interface bus
(however, a system may contain more than one interface bus). The
maximum total accumulative cable length for one interface bus may
not exceed twice the number of instruments connected (in meters) , or
20 meters—whichever is less.
The instruments on the bus are connected in parallel, as shown in
Figure 1-1. Eight of the signal lines (DIO1 thru DIO8) are used for
the transfer of data and other messages in a byte-serial, bit-parallel
form. The remaining eight lines are used for communications timing
(handshake), control, and status information. Data are transmitted on
the eight GPIB data lines as a series of eight-bit characters, referred
to as bytes.
Data transfer is by means of an interlocked handshake technique
(Figure 1-2). This technique permits asynchronous communications
over a wide range of data rates. The following paragraphs provide an
overview of the data, and handshake buses, and describe how these
buses interface with the 360B VNA.
GENERAL GPIB DESCRIPTION OF THE IEEE-488
INFORMATION (IEC-625) INTERFACE BUS
360B GPIB PM 1-5

HANDSHAKE Lines
(3 signal lines)
(5 signal lines)
(e.g. EXTERNAL
COMPUTER)
(e.g. 360B VNA)
DATA LINES
Data Byte
Transfer Control
Data Bus
General Interface
Management
IEEE-488 BUS (16 Lines)
DEVICE D
Only able to talk
DEVICE C
Only able to listen
DEVICE B
Able to talk
and listen
DEVICE A
Able to talk, listen,
and control
(8 signal lines)
Note:
Management
CONTROL Lines
The configuration shown in this diagram depicts an
external computer connected via GPIB to a 360B VNA
and other microwave instruments. The second dedicated
GPIB that is part of the 360B VNA is not shown (refer to
Figure 2-1 in the next section).
(e.g. OTHER
INSTRUMENT**)
(e.g. OTHER
INSTRUMENT**)
DATA INPUT/OUTPUT,
DIO 1 thru DIO 8
DAV
NRFD*
NDAC*
IFC
ATN
SRQ
REN
EOI
- DATA VALID
- NOT READY FOR DATA*
- NOT DATA ACCEPTED*
- INTERFACE CLEAR
- ATTENTION
- SERVICE REQUEST
- REMOTE ENABLE
- END OR INDENTIFY
NEGATION IS
REPRESENTED
BY LOW STATE ON
THESE TWO LINES
**IF USED
*
Figure 1-1. Interface Connections and Bus Structure
GENERAL GPIB DESCRIPTION OF THE IEEE-488
INFORMATION (IEC-625) INTERFACE BUS
1-6 360B GPIB PM

IEEE-488
Hardware
Interface
The IEEE-488 interface bus hardware implementa-
tion is made up of 16 signal lines that comprise
three functional groups (Figure 1-1).
Data Bus (8 lines)
Data Byte Transfer Control Bus (3 lines)
General Interface Management Bus (5 lines)
The signal lines in each of the three groups are des-
ignated according to function. Table 1-1 lists these
designations.
Data Byte
Transfer
Control Bus
Description
Control of information transfer on the GPIB data
Bus is accomplished by a technique called the
“three-wire handshake”, which involves the three
signal lines of the Data Byte Transfer Control Bus.
This technique is described briefly below and is de-
picted in Figure 1-2. For further information, refer
to the ANSI/IEEE Std 488-1978 document.
DAV (Data Valid)
This line goes TRUE (arrow 1) when the talker has
(1) sensed that NRFD is FALSE, (2) placed a byte of
data on the bus, and (3) waited an appropriate
length of time for the data to settle.
NRFD (Not Ready For Data)
This line goes TRUE (arrow 2) when a listener indi-
cates that valid data has not yet been accepted. The
time between the events shown by arrows 1 and 2 is
variable and depends upon the speed with which a
listener can accept the information.
Bus Type Signal Line
Name Function
Data Bus DIO1–DIO8 Data Input/Output, 1 thru 8
Data Byte Trans-
fer and Control DAV NRFD
NDAC
DataAvailable
Not Ready For Data
Not Data Accepted
General
Interface Control ATN IFC
SRQ
REN
EOI
Attention
Interface Clear
Service Request
Remote Enable
End Or Identify
Table 1-1. Interface Bus Signal Line Designations
GENERAL GPIB DESCRIPTION OF THE IEEE-488
INFORMATION (IEC-625) INTERFACE BUS
360B GPIB PM 1-7