Anritsu 68147A Programming Manual

SERIES
681XXA

SYNTHESIZED SWEEP GENERATOR

PROGRAMMING MANUAL

PRELIMINARY

490 JARVIS DRIVE
MORGAN HILL, CA 95037-2809

P/N: 10370-10254

PRINTED: MARCH 1993

COPYRIGHT 1993 WILTRON CO.

REVISION: A

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 and all
microwave components, 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, unauth or ized modification or misuse, or oper ation outside of the environmen tal
specification s of the produc t. No other warran ty i s expressed or implied, an d the remedies pr ovided
herein are the Buyer’s sole and exclusive remedies.

TABLE OF CONTENTS

Chapter 1 — General GPIB Information

Chapter 1 provides a general description of the General Purpose Interface Bus (GPIB) and the bus
data transfer and control functions. It also contains a listing of the 681XXA’s GPIB interface func­tion subset capability and response to IEEE-488 interface function messages. Chapter contents are
detailed immediately following the tab.

Chapter 2 — Programming with SCPI Co mmands

Chapter 2 provides information for remote operation of the sweep generator via the GPIB using
Standard Commands for Programmable Instruments (SCPI) commands. All SCPI commands are
listed and described by subsystem. Sample programs showing usage of the commands are also in­cluded. Chapter contents are detailed immediately following the tab.

Chapter 3 — Programmi ng with Compatible 67XX GPIB Comman ds

Chapter 3 provides information for remote operation of the sweep generator via the GPIB using
compatible WILTRON Model 67XX Synthesizer GPIB commands. All 67XX GPIB commands ac-
cepted and implemented by the 681XXA are listed and described by function. Sample programs
showing usage of the commands are also included. Chapter contents are detailed immediately fol­lowing the tab.

Appendix A — SCPI Conformance Information

Appendix A provides SCPI conformance information in the form of a command summary.

Appendix B — Index of Compatible 67XX GPIB Commands

Appendix B provides an alphabetical index of the WILTRON Model 67XX GPIB Product Specific
Commands accepted and implemented by the 681XXA.

681XXA PM PRELIMINARY i

Chapter 1
General GPIB Information

Table of Contents

1-1 SCOPE OF MANUAL . . . . . . . . . . . . . . . . 1-3

1-2 INTRODUCTION . . . . . . . . . . . . . . . . . . 1-3

1-3 IEEE-488 INTERFACE BUS DESCRIPTION . . . 1-5

Functional Elements . . . . . . . . . . . . . . . . 1-6

Bus Structure . . . . . . . . . . . . . . . . . . . . 1-7

Data Bus Description . . . . . . . . . . . . . . . . 1-7

Data Byte Transfer Control Bus Description . . . 1-8
General Interface Management Bus Description . 1-9

Device Interface Function Capability . . . . . . . 1-10

Message Types . . . . . . . . . . . . . . . . . . . 1-11

1-4 681XXA GPIB OPERATION . . . . . . . . . . . . . 1-13

Setting GPIB Operating Parameters . . . . . . . 1 -13

Response to GPIB Interface Function Messages . 1-13

Chapter 1
General GPIB Information

1-1

1-2

SCOPE OF MANUAL

INTRODUCTI ON

This manual prov ide s infor mation for oper atin g the Ser ies 681X XA
Synthesized Sweep G en era tor with command s sen t from an exter nal
controller via the IEEE-488 Gener al Purpose In ter fac e Bus (GP IB). It
includes the following:

A gene ral desc r iption of the GPIB and the bus data tran sfer and
control func tion s.
A complete l isting and desc rip tion of all the Standard Comman ds
for Programmable Instrument s (SCPI) commands used to control
sweep generator operation with programming examples.
A complete l isting and desc rip tion of all compa tible WILT RON
67XX Synthesizer GPIB co mmand s that can be used to contr ol
sweep generator operation with programming examples.

This manual i s intend ed to be use d in conju n ction with the Series
681XXA Synthesized Sweep Generator Op era tion Manual, P/N 10370-

10250. Refer to that manual for general information about the
681XXA, including equipment set up and front panel (manual mode)
operating instr uc tion s.

This chapter prov ides a gener al descr iption of the GPIB and the bus
data transfer and control functions. It also contains a listing of the
681XXA’ s GPI B inter fac e func tion subset capability an d respo nse to
IEEE-488 interface function messages.

The GPIB information presen ted in this chapte r is general in natu r e.
For complete and specific information, refer to the following docu­ments: ANSI/IEEE Std 488.1-1987 IEEE Standard Digital Interface

for Programmable Instrumentation and ANSI/I EEE S td 488.2- 1987
IEEE Standar d Code s, For mats , Prot ocols an d Common Comman ds.

These documen ts prec isely defin e the total specification of the me­chanical an d elec tric al inter fac e, and of the data tran sfer and co ntr ol
protocols.

681XXA PM PRELIMINARY 1-3

GENERAL GPIB IEEE-488 INTERFACE
INFORMATION BUS DESCRIPTION

IEEE-488 BUS (16 Lines)

DEVICE A

Able to talk, listen,
and control

(e.g. COMPUTER)

DEVICE B

Able to talk and listen

(e.g. 681XXA
SWEEP
GENERATOR)

DEVICE C

Data Bus
(8 signal lines)

Data Byte Transfer
Control Bus

(3 signal lines)

DATA LINES

HANDSHAKE Lines

Only able to listen

(e.g. OTHER
INSTRUMENT**)

DEVICE D

Only able to talk

(e.g. OTHER
INSTRUMENT**)

General Interface
Management Bus

(5 signal lines)

DATA INPUT/OUTPUT,
DIO 1 thru DIO 8

DAV - DATA VALID
NRFD - NOT READY FOR DATA*
NDAC - NOT DATA ACCEPTED*

IFC - INTERFACE CLEAR
ATN - ATTENTION
SRQ - SERVICE REQUEST
REN - REMOTE ENABLE
EOI - END OR IDENTIFY

* NEGATION IS REPRESENTED BY
LOW STATE ON THESE TWO LINES

** IF USED

Figure 1-1. Interface Connections and GPIB Bus Structur e

Management
CONTROL Lines

1-4 PRELIMINARY 681XXA PM

GENERAL GPIB IEEE-488 INTERFACE
INFORMATION BUS DESCRIPTION

1-3

IEEE-488 INTERFACE
BUS DESCRIPTION

The IEEE-488 Gener al Purpo se Interfac e Bus (G PIB) is an instrumen ­tation interface for integrating instruments, computers, printers, plot­ters, and other measur eme nt dev ic es in to sys tems. The GPIB uses 16
signal lines to effect transfer of inf orm ation betw een all devic es con ­nected on the bus.

The following re quirements and restrictions apply to the GPIB.

No more than 15 devices can be inter con ne cted by one contiguous
bus; however, an instru men tation system may contain more than
one interface bus.
The maximum total cumu l ative cable length for one inter fac e
bus may not exceed twice the number of devices connected (in me­ters) , or 20 meters—whichev er i s less.
A maximu m data rate of 1 Mb/s across the inter fac e on any sig­nal line.
Each device on the interface bus mus t have a unique addr ess,
ranging from 00 to 30.

The devices on the GPIB are co nnec ted in parallel, as shown in Figur e
1-1. The interface consists of 16 signal lines and 8 ground lines in a
shielded cable. Eight of the signal lines are the data lines, DIO 1 thru
DIO 8. These data lines carry messages (data and comman ds), one
byte at a time, among the GPIB devic es. Th ree of the re mainin g line s
are the handshake line s that control the transfer of message bytes be­tween devices. The five remaining sign al line s are refer re d to as inter­face management lines.

The follow ing par agr aph s p rovide an overview of the GPIB in clu din g a
description of the function al elemen ts, bus str u ctu re, bu s data trans­fer process, in terf ace manag emen t bus, dev ic e inter face function re­quiremen ts, and message types.

681XXA PM PRELIMINARY 1-5

GENERAL GPIB IEEE-488 INTERFACE
INFORMATION BUS DESCRIPTION

Functional
Elements

Effective commun ication s betwee n devic es on the
GPIB requires three functional elements; a talker, a
listener, and a controller. Each device on the GPIB
is categorized as one of these elements depending
on its current interface function and capabilities.

Talker

A talker is a device capable of sending devic e-de ­penden t data to another device on the bus when ad­dressed to talk. Only one GPIB device at a time can
be an active talker.

Listener

A l i stener i s a device capable of r ec eiv ing dev ice-de­pendent data from anoth er device on the bus when
addres sed to listen . An y nu mber of GPIB devices
can be listeners simultaneously.

Controller

A co ntr oller is a device, usually a compute r, capable
of managin g the oper a tion of the GPIB. Only one
GPIB device at a time can be an active contro ller.
The active controller manages the transfer of device­depende nt data betw een GPIB devices by desig n a t­ing who will talk and who will listen.

System Control ler

The system controlle r is the device tha t always re­tains ultimate control of the GPIB. When the sys­tem is first powered-up, the system controller is the
active controller and manages the GPIB. The sys­tem controller can pass contro l to a device, makin g
it the new active controller. The new activ e contr ol­ler , in turn, may pass control on to yet another de­vice. Even if it is not the active controller, the
system contro ller maintains co ntr ol of the Inter fac e
Clear (IFC) and Remote Enable (REN) inter fac e
managemen t lines and can thus tak e control of the
GPIB at anytime.

1-6 PRELIMINARY 681XXA PM

GENERAL GPIB IEEE-488 INTERFACE
INFORMATION BUS DESCRIPTION

Bus
Structure

The GPIB uses 16 signal lines to carry data and
commands between the device s conne cted to the
bus. The interfac e sign al line s are orga n ized in to
three function al gr ou ps.

Data Bus (8 lines)
Data Byte Transfer Control Bus (3 lines)
General In terf ace Management Bus (5 line s)

The signal lines in each of the thr ee grou ps are des­ignated accordin g to function . Table 1-1 lists these
designation s.

Table 1-1. Interface Bus Signal Line Designations

DAV
NRFD
NDAC

ATN
IFC
SRQ
REN
EOI

Signal Lin e

Name

Function

Data Ava ilable
Not Ready For Da ta
Not Data Acc epted

Attenti on
Interface Clear
Service Request
Remot e E nable
End Or Identify

Bus T y pe

Data Bus DIO1–DIO 8 Data Input/Out pu t, 1 thru 8
Data Byte

Tra nsfer
Control Bus

Genera l
Interface
Management
Bus

Data Bus De­scription

The data bus is the conduit for the transfer of data
and commands between the devic es on the GPIB. It
contains eigh t bi-dir ec tion al, active-low signal lin e s
—DIO 1 thru DIO 8. Data and commands are trans ­ferred over the data bus in byte-ser ial, b it-par allel
form. This means tha t one byte of data (eight bits)
is transferred ov er the bus at a time. DIO 1 repre­sents the least-signific ant b it (LSB) in this byte and
DIO 8 represen ts th e mo st-sig n ific ant b it (MSB).
Bytes of data are normally formatted in seven-bit
ASCII (American Standar d Code for Inf orm ation In­terchang e) code. The eigh th (parity ) bi t is not used.

Each byte placed on the data bus repr esen t s either
a command or a data byte. If the Attention (ATN) in­terface manage men t line is TRUE while the data is
transfer red, the n the data bus is carry in g a bus com­mand whic h is to be receiv ed by ev er y GPIB devic e.
If A T N is FALSE, then a data byte is being tran s­ferred and only the active listeners will receive that
byte.

681XXA PM PRELIMINARY 1-7

GENERAL GPIB IEEE-488 INTERFACE

1st Data Byte 2nd Data Byte

Valid

Not

Valid

Valid

Not

Valid

All

Ready

None

Ready

All

Ready

None

Ready

All

Accept

None

Accept

None

Accept

All

Accept

DIO1-DIO8

(composite)

DAV

NRFD

NDAC

INFORMATION BUS DESCRIPTION

Figure 1-2. Typical GPIB Handshake Op eratio n

Data Byte
Transfer
Control Bus
Description

Control of the tran sfer of eac h by te of data on the
data bus is accomplished by a techn ique called the
“three-wire handshake”, which involv es the thr ee
signal lines of the Data Byte Transfer Contr ol Bus.
This technique forces data transfers at the spe ed of
the slowest listener, which ensures data integrity in
multiple listener transfers. O ne line (DAV) is con­trolled by the talker, while the other two (NRFD
and NDAC) are wire d-O R lines sh ar ed by all active
listeners. The handsh ake lin es, like the other GPIB
lines, are active low. The techniqu e i s described
briefly in the follow in g par ag rap hs and is depicted
in Figure 1-2. For fur ther inf or ma tion, refer to
ANSI/IEEE Std 488.1.

DAV (Data Valid)

This line is controlled by the active talker. Before
sending any da ta, the talker verifie s that NDAC is
TRUE (active low) which ind icates that all listeners
have accepte d the prev iou s data byte. The talker
then places a byte on the data lines and waits un ti l
NRFD is F ALSE (high ) which indicates that all ad­dressed listener s are read y to accept the infor m a­tion. When both NRFD and ND AC are in the prop er
state, the talker sets the DAV line TRUE (active
low) to indicate that the data on the bus is valid
(stable).

NRFD (Not Ready For Data)

This line is used by the listeners to infor m the
talker when they are ready to accept new data. The
talker must wait for each listener to set the NRFD
line FALSE (high) which they will do at their own

1-8 PRELIMINARY 681XXA PM

GENERAL GPIB IEEE-488 INTERFACE
INFORMATION BUS DESCRIPTION

rate. This assures that all devices that are to accept
the data are ready to receive it.

NDAC (Not Data Accepted)

This line is also controlled by the listeners and is
used to inform the talke r that each devic e a d­dressed to listen has accep te d the data. Each devic e
releases NDAC at its own rate, but NDAC will not
go FALSE (high) until the slowest listener has ac­cepted the data byte.

General
Interface
Management
Bus
Description

The general inter fac e manag eme nt bus is a group of
five signal lin es used to manag e the flow of info rma­tion across the GPIB. A description of the function
of each of the indiv idu al con tro l lines is prov ided be­low.

ATN (Attention)

The activ e co ntroller uses the ATN line to define
whether the information on the data bus is a com­mand or is data. When ATN is TRUE (low), the bus
is in the command mode and the data lines carr y
bus commands. Wh en ATN is FALSE (high), the bus
is in the data mode and the data lines carry devic e­depende nt instr uction s or data.

EOI (End or Identify)

The EOI line is used to indicate the last byte of a
multibyte data transfer. The talker sets the EOI
line TRUE during the last data byte.

The active contro ller also uses the EOI line in con­junction w ith the ATN line to initiate a parallel poll
sequence.

IFC (Interface Clear)

Only the system controller uses this line. When IFC
is TRUE (low), all devices on the bus are placed in a
known, quiescen t state (unaddressed to talk, unad­dressed to listen, and se rvic e re que st idle).

REN (Remote Enab le)

Only the system controller uses this line. When
REN is set TRUE (low), the bus is in the remote
mode and devices are addre ssed either to listen or
to talk. When the bus is in remote and a device is
addres sed, it receiv es instru c tion s from the GPIB
rather than from its front panel. When REN is set
FALSE (high) , the bus and all devic es return to lo­cal operation.

681XXA PM PRELIMINARY 1-9

GENERAL GPIB IEEE-488 INTERFACE
INFORMATION BUS DESCRIPTION

SRQ (Service Request)

The SRQ line is set TRUE (low) by any device r e­questing service by the activ e contr oller.

Device
Interface
Function
Capability

An interfac e fu n ction is the GPIB system element
which provides the basic operation al fac ility
through which a device can receive, process, and
send messages. Each specif ic interf ace function may
only send or receive a limited set of messages
within partic ular cl asses of messages. As a re sult, a
set of interface fun ction s is necessar y to achiev e
complete commun ic atio ns amon g devic es on the
GPIB. ANSI/IEEE Std 488.1 d efin es eac h of th e
interface functions along with its specific protocol.

ANSI/IEEE Std 488.2 specifies the minimum set of
IEEE 488.1 interface capabilities that each GPIB de­vice must have. This minimu m set of interfac e fun c­tions assures that the device is able to send and
receive data, r equ es t service, and r epon d to a devic e
clear message. Table 1-2 lists the interface function
capability of the series 681XXA sweep generator.

T abl e 1-2. 681XXA Inter face Function Capab il ity

Function
Identifier

AH1 Acceptor Handshake Complete Capabi lity

Function 681XXA Capability

SH1 Source Handshake Complete Capa bility

T6 Talker No Talk Only (TO N)

L4 Listener No Listen Only (LON)
SR1 Service Request Complete Capab ility
RL1 Remote/Local Complete Capabi lity
PP1 Parallel Poll Complete Capabi lity
DC1 Device Clear Complete Capability
DT1 Device Trigger Complete Capab i lity

C0 Controller No Capability

E2 Tri-State Drivers Three-state bus drivers

1-10 PRELIMINARY 681XXA PM

GENERAL GPIB IEEE-488 INTERFACE
INFORMATION BUS DESCRIPTION

Message
Types

There are three types of information transmitted
over the GPIB—inte rface func tion messages, device ­specific comman ds, and data and instrumen t status
messages.

Interface Fun cti o n Mess ages

The controller manages the flow of information on
the GPIB using interface func tion messages, usu­ally called comma nds or command messages. Inter-
face function messages perfo rm such function s as
initializing the bus, addressing and unaddr essing
devices, and setting device modes for remote or local
operation .

There are two types of commands—mu ltilin e and
uniline. Multilin e command s are bytes sent by the
active contr oller over the data bus (DIO 1-D IO 8)
with A TN set TRUE. Un ilin e c omman ds ar e sign al s
carried by the indiv idu al inter fac e manag eme nt
lines.

The user generally has control over these com­mands; however , the extent of user control depends
on the implementation and varies with the specific
GPIB interfac e har dw ar e and software used with
the external contr oller.

Device-Speci fic Comma nd s

These commands are ke ywor ds or mnemon ic cod es
sent by the external con trolle r to contr ol the setup
and operation of the addr essed dev ic e or ins tru­ment. The commands are normally uniqu e to a par­ticular in strument or class of instrument s and are
described in its documentation.

Device-specific commands are transmitted over the
data bus of the GPIB to the device in the form of
ASCII strings containing one or more keywords or
codes.They are decoded by the device’s internal con-
troller and cause the various instr u men t function s
to be performed .

Data and Instrument Status Messages

These messages are sent by the device to the exte r­nal controller via the GPIB. They con tain measur e­ment results, instrume nt status, or data files that
the device tran smits over the data bus in respon se
to specific requests from the extern al con tro ller. The
content s of these messages are instr ume nt spec ific
and may be in the form of ASCII string s or binar y
data.

681XXA PM PRELIMINARY 1-11

GENERAL GPIB IEEE-488 INTERFACE
INFORMATION BUS DESCRIPTION

In some cases data messages will be transmitted
from the external controller to the device. For exam­ple, messages to load calibration data.

An SRQ (service r equest) is an interface fun ction
message sent from the device to the external control­ler to request service fro m the contr oller, usually
due to some predetermin ed statu s condition or er­ror. To send this message, the device sets the SRQ
line of the General Interface Manageme nt Bus true,
then sends a status byte on the data bus lines.

An SRQ interface fun ction message is also sent by
the device in resp onse to a serial poll message from
the controller, or upon rec eiv ing an Outpu t Status
Byte(s) command fro m the contr oller. The protoco l s
associated with the SRQ function s are defin ed in
the ANSI/IEEE Std 488.2 docu men t.

The manner in whic h interface func tion messages
and device-spe cif ic comman ds are invok ed in pro­grams is implementation specific for the GPIB inter­face used with the exte rnal co ntr oller. Even though
both message types are represented by mne mon ics,
they are implemented and used in different ways.

Normally, the interface function messages are sent
automatically by the GPIB driver softwar e in re­sponse to invoc ation of a software fu nction . For ex­ample, to send the IFC (Interface Clear ) interface
fuction message, one would call the ibsic function of
the National Ins trumen t s software driv er. On the
other hand, the command *RST (Reset) is sent in a
command string to the addressed devic e. In the case
of the National Instru men ts example, this would b e
done by using the ibwrt function call.

1-12 PRELIMINARY 681XXA PM

GENERAL GPIB 681XXA GPIB
INFORMATION OPERATION

1-4

681XXA GPIB
OPERATION

All Series 681XXA Synthesized Sweep Generator function s, settings,
and operating modes (excep t for pow er on/s tandby ) ar e contr ollable us­ing commands sent fr om an external co ntr oller via the GPIB. Whe n in
the remote (GPIB) mode, the synthe sizer fun ction s both a s a listener
and a talker. The GPIB interface func tion capability of the 681XX A is
listed in Table 1-2 (page 1-10).

Setting
GPIB Oper­ating Pa­rameters

Response to
GPIB
Interface
Function
Messages

The 681XXA leaves the fac tory with th e GP IB ad ­dress value set to 5 and the data delimiting termin a­tor set to carr iage return and line feed (CR/LF). A
different ad dre ss value can be entered fr om the
front panel usin g the Config u re GPI B menu . Using
this same menu, the data delimiting terminator can
be changed to car riag e retu r n (CR) only. Refer to
Chapter 2 of the Series 681XXA Synthesized Sweep
Generator Operation Manual for the procedure.

Table 1-3 (page 1-14) lists the GPIB Interface Func­tion Messages that the 681XXA will recognize and
respond to. With the exception of the Device Clear
and Selected Devic e Clear messag es, the se mes­sages affect only the operation of the 681XXA GPIB
interface. The 681XXA response for each message is
indicated.

Interfac e fun ction messages are transmitted on the
GPIB data lines and inter fac e manageme nt line s as
either unaddressed or addr essed co mmand s. The
manner in which these messages are invoked in pro­grams is implemen tation dependent. For program­ming information , refe r to the documentation
included w i th the GPIB Inte rface for the external
controller used.

681XXA PM PRELIMINARY 1-13

GENERAL GPIB 681XXA GPIB
INFORMATION OPERATION

T abl e 1-3. 681XXA Resp ons e to GPIB Interface Func tion Mes sages

Interface Function Message

Device Clear (DCL)
Selected Device Clear (SDC)

Go To Local (G TL) Yes Returns the 681 X XA to local (front

Group Exe cut e Trigger
(GET)

Interface C lear (IF C) No Stops the 681XXA GPIB interface

Local Lockout (LLO) No Disables the front panel menu

Remote Enable (REN) No Places the 681XXA under remote

Serial-Poll Enable (SPE) No Outputs the serial-pol l status byte.
Serial-Poll Disable (SPD) No Disables the serial-poll function.
Parallel-Poll Configure (PPC) Yes Responds to a parallel-poll

Addressed

Command

No

Yes

Yes Executes a string of commands, if

Resets the 681XXA to its default
state. (Equivalent to sending the
*RST command.)

panel) control.

program med.

from listening or talking. (The front
panel controls are not cleared.)

RETURN TO LOCAL soft-key.

(GPIB) cont ro l wh e n it has been
addressed t o l iste n.

message (PPOL L) by setting
assigned data bus l ine to the logica l
state (1,0 ) that indicat es it s cor rec t
SRQ status.

681XXA Response

Parallel-Poll Unconfigure
(PPU)

No Disables the parallel-poll function.

1-14 PRELIMINARY 681XXA PM

Chapter 2
Programming with
SCPI Commands

– SCPI Programming Informati on wil l be supp lied at a later date. –

Chapter 3
Programming with
Compatible 67XX
GPIB Commands

Table of Contents

3-1 INTRODUCTION . . . . . . . . . . . . . . . . . . 3-3

3-2 COMMAND CODES . . . . . . . . . . . . . . . . . 3-3

3-3 DATA INPUT RESTRICTIONS . . . . . . . . . . . 3 -5

3-4 PARAMETER AND DAT A ENTR Y COMMANDS . 3-6

Opening a Parameter . . . . . . . . . . . . . . . . 3-6

Data Entry . . . . . . . . . . . . . . . . . . . . . 3-6

Using the SYZ Command . . . . . . . . . . . . . . 3-9

3-5 CW FREQUENCY COMMANDS . . . . . . . . . . 3-10

3-6 ANALOG AND STEP SWEEP COMMANDS . . . . 3 -11

Sweep Range . . . . . . . . . . . . . . . . . . . . 3-11

Alternate Sweep . . . . . . . . . . . . . . . . . . . 3-12

Sweep Triggering . . . . . . . . . . . . . . . . . . 3 -12

Analog/Step Sweep Select . . . . . . . . . . . . . 3-14

Special Step Sweep . . . . . . . . . . . . . . . . . 3-16

3-7 FREQUENCY MARKER COMMANDS . . . . . . 3-16

3-8 MODULATION COMMANDS . . . . . . . . . . . . 3-18

Amplitude Modulation . . . . . . . . . . . . . . . 3-18

Frequency Modulation . . . . . . . . . . . . . . . 3-18

Square Wave Modulation . . . . . . . . . . . . . . 3-18

3-9 OUTPUT POWER LEVELING COMMANDS . . . 3-20

3-10 OUTPUT COMMANDS . . . . . . . . . . . . . . . 3-22

3-11 STORED SETUP COMMANDS . . . . . . . . . . . 3-24

3-12 SRQ AND STATUS BYTE COMMANDS . . . . . . 3-26

Status Bytes . . . . . . . . . . . . . . . . . . . . . 3-26

SRQ Generation . . . . . . . . . . . . . . . . . . . 3 -26

3-13 CONFIGURATION COMMANDS . . . . . . . . . . 3-31

3-14 GROUP EXECUTE TRIGGER COMMANDS . . . 3-32
3-15 FAST-FREQUENCY-SWITCHING COMMANDS . 3-33

3-16 POWER-OFFSET-TABLE COMMANDS . . . . . . 3-34

Loading the Power-Offset Table . . . . . . . . . . 3-34

3-17 SELF TEST COMMANDS . . . . . . . . . . . . . . 3-37

3-18 MISCELLANEOUS COMMANDS . . . . . . . . . 3-39

3-19 PROGRAM ERRORS . . . . . . . . . . . . . . . . 3-40

Invalid-Parameter . . . . . . . . . . . . . . . . . 3-40

Syntax . . . . . . . . . . . . . . . . . . . . . . . . 3-40

3-20 RESET PROGRAMMING AND DEFAULT

CONDITIONS . . . . . . . . . . . . . . . . . . . . 3-41

3-21 PROGRAMMING EXAMPLES . . . . . . . . . . . 3-42

Chapter 3
Programming with
Compatible 67XX
GPIB Commands

3-1

3-2

INTRODUCTION

COMMAND CODE S

This chapter prov ides info rmation for remote oper a tion of the Serie s
681XXA Synthesized Sweep Gene rator via the GPIB using compa tible
WILTRON Mod el 67XX Synthesizer GPI B comman ds. All 67XX GPIB
commands accepted and impleme nted by the 681XXA are listed and de­scribed by function . Sample progr am s showing usage of the command s
are also included.

There are over two hundred and forty 67XX GPIB commands that are
accepted and implemen ted by the 681XXA. These GP IB comman ds a l­low the user to program all front pan el and men u func tions (ex cept for
power on/standby). Each GPIB command is a two- or three-character
mnemonic co de that represents an instrume nt co mmand or parameter;
for example: RST (reset).

Table 3-1, beginning on page 3-4, is a listing of all 67XX GPIB com­mand mnemonic co des acc ep ted and implemen ted by the 681XX A
grouped into func tion al categ or ies. The listin g for eac h catego ry in­cludes referen c es to the paragrap h an d page number in this chapter
where a complete description of that group of commands can be found.

NOTE

A quick way to determine the function of any of the GPIB
command codes listed in Table 3-1 is to look up the command
code of interest in Appendix B of this manual. Appendix B is
an alphabetical index of all compatible 67XX GPIB command
codes. A brief description of the function of each command is
also included.

681XXA PM PRELIMINARY 3-3

PROGRAMMING WITH COMPATIBLE COMMAND
67XX GPIB COMMANDS CODES

Table 3-1. Compatible 67XX GPIB Command Codes Listed by Function (1 of 2)

GPIB Command
Group Function

Param eter Entry
Commands

Data Entry/
DataTerminator
Commands

CW Frequency
Commands

Analog and Digital
Sweep Comm ands

Frequenc y Marke r
Commands

Modulatio n
Commands

Command Cod es Para. Page

F0, F1, F2, F3, F4, F5, F6, F7, F8, F9, M0,
M1, M2, M3 , M4 , M5, M6, M7, M8, M9,
DLF, DFF, DFM, SDT, SNS, SWT, LOS,
PDT, PNS, FMS, UP, DN, SYZ, CLO

0 thru 9, –, ., CLR, DB, DM, GH, MH, KH,
HZ, SEC, MS, US, G V, MV, K V, PCV, SPS

CF0, CF1, CF2, CF3, CF4, CF5, CF6,
CF7, CF8, CF9, CM0, CM1, CM2, CM3,
CM4, CM5, CM6, CM7, CM8, CM9, SQF,
SQU, SQ D, ACW

SF1, SF3, FUL, DF0, DF1, DF5, DF6,
AFU, AF1, AF3 , AD1, AD5, AD6, A UT, EXT ,
TRG, TRS, RSS, SWP, SSP, MAN, DU1,
DU0, TSS, SP1, S P0

ME1, ME0, MK0, IM1, VM1 3-7 3-16

AM0, A M1, AM2, FM0, FM 1, FMS, FMW,
FMU, P0, SQP, SW0, SW1, SW2, SW3,
SW4, XP

3-4 3-6

3-4 3-6

3-5 3-10

3-6 3-11

3-8 3-18

Power Leveling
Commands

Output Commands OI, OFL, OFH, OF0, OF1, OF2, OF3, OF4,

Stored Set up
Commands

Service Request
and Stat us Byt e
Commands

Configura tion
Commands

Group Execute
Trigger (GET)
Commands

L1, L2, RF1, RF0, LO1, LO0, IL1, DL1,
PL1, LV0, LSP, EG1 , EG0

OF5, OF6, O F7, OF8, OF9, O M0, OM1,
OM2, OM3, OM4, OM5, OM 6, OM7, OM8,
OM9, OL1, OL2, OLO, ODF, OPD, OPS,
OSD, OSS, OST , OVN, OWT, OSE, OEM,
OES, OSB,OSM, OSR

SAF, SAM, SM, SSN(M

1-9

)

RSN(M
SQ1, SQ0, ES1 , ES0, UL1, UL0, LE1,

LE0, PE1, PE0, SE1 , SE0, FB1, FB0,SB1,
SB0, MB0, MB1, MB2, EL1, EL0, CSB

BPN, BPP, EP0 , EP1, PP0, PP1, RC0,
RC1, RT0, R T 1

GTC, GTD, GTF, GTL, GTO, GTS, GTT,
GTU, Y

), RCF, RCM,

1-9

3-9 3-20

3-10 3-22

3-11 3-24

3-12 3- 26

3-13 3- 3 1

3-14 3- 32

3-4 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE DATA INPUT
67XX GPIB COMMANDS RESTRICTIONS

Table 3-1. Compatible 67XX GPIB Comm an d Code s Listed by Function (2 of 2)

3-3

DATA INPUT
RESTRICTIONS

GPIB Command

Group Funct io n

Fast-Freque ncy­Switching
Commands

Power-Offset­Table Command s

Self Test
Commands

Miscellaneous
Commands

ZL(X

PT0, PT1, PTC, PTL 3-16 3-34

TST 3-17 3-37

CS0, CS1, DS0, DS1, RL, RST, SNR 3-18 3-39

Command Codes Para. Page

), ZEL, ZS(X

000-999

000-999)

3-15 3-33

The 681XXA sweep gene rator does not accept paramete r or data en­tries in an expon en tial o r scie ntific no tation for mat. Th e acc epted data
formats are as follows:

A decimal or inte ger format for enterin g parameter s and data.
A binary-byte forma t for ente ring bo th the s tatus by te mask com­mands (para. 3-12) and the RCF and RCM stor ed -setup com-
mands (para. 3-11).

Progr am min g Note: The sweep generator only reco gnizes the follow­ing 65 characters:

The 52 upper - and low er-case alphabetic ch arac ter s. (T he 681XX A
accepts both upper - and lower-case character s with out distin­guishing between the cases).
The minus sign (–).
The comma (,).
The decimal point (.).
The numerals between 0 and 9.

All character s other than the 65 listed above ar e ignor ed an d can be in­terspersed betw een meanin gfu l char acter s with ou t ill effect. Th is use
of other charac ters can impr ove read ability. For examp le, the two com­mand strings below are valid and interchangable.

“F12.754GHF27.792GHSF1SWPMK0L12DM”
“F1=2.754 GH, F2=7.792 GH, SF1, SWP, MK0, L1=2 DM”

681XXA PM PRELIMINARY 3-5

PROGRAMMING WITH COMPATIBLE PARAMETER AND DATA
67XX GPIB COMMANDS ENTRY COMMANDS

3-4

P ARAM ETER AND DATA
ENTRY COMMANDS

Table 3-2 lists the comman d mne mon ic codes that open parame ters for
data entry. The table also provid es the ran ge of values per mi tted for
each parameter and the data termin ator mnemon ic codes for eac h. Ta­bles 3-3 and 3-4, located on page 3-8, list the data entry and data termi­nator command mnemonic codes.

Opening a
Parame ter

Data Entry When a parameter is open for data entry, its value

All of the commands listed in Table 3-2 open a pa­rameter for data entry. Once opened, a parameter re­mains open until one of the following occurs:

Another parameter is opened.
A fu nc tion other than video marker s, intensity
markers, or outpu t power lev elin g is com­manded.
The CLO (close open parameter ) comman d is re­ceived.

can be changed as follows:

By sending a nu mer ic value follow ed by the ap­propriate terminator code.
By incrementing or decrementing its value us­ing an associated step size.

NOTE

An appropriate data terminator must be
used to terminate a numeric-par ameter en ­try, and it must immediately follow the nu­meric value. If it does not, a parameter en try
error will result.

The parameter and data entry commands do no t affect the sweep ge n­erator’s output unless the parameter bein g changed is also the curren t
output parame ter. The comman ds, theref or e, may be used to chan g e
the preset valu es of parameters without altering the 681X XA’s output.

Example: Assume that the 681X X A is executing an F3-F4 sweep from
3 GHz to 10 GHz. Chang in g the value of F1 to 3 GHz with the com­mand string “F1 3 GH” does not affect the current output of the sweep
generator. However, chang in g the value of F4 with the comman d strin g
“F4 16.01 GH” alters the output of the 681XXA because it change s
the end point of the F3-F4 sweep to 16.01 GHz.

3-6 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE PARAMETER AND DATA

MNEMONIC

CODE

PARAMETER V ALUES TERMINATOR

F0
F1
F2
F3
F4
F5
F6
F7
F8
F9

Opens t he F0 pa ram eter
Opens t he F1 pa ram eter
Opens t he F2 pa ram eter
Opens t he F3 pa ram eter
Opens t he F4 pa ram eter
Opens t he F5 pa ram eter
Opens t he F6 pa ram eter
Opens t he F7 pa ram eter
Opens t he F8 pa ram eter
Opens t he F9 pa ram eter

Dependent on the
frequency range of
the instrument

GH
MH
KH

HZ

M0
M1
M2
M3
M4
M5
M6
M7
M8
M9

Opens t he M0 par ameter
Opens t he M1 par ameter
Opens t he M2 par ameter
Opens t he M3 par ameter
Opens t he M4 par ameter
Opens t he M5 par ameter
Opens t he M6 par ameter
Opens t he M7 par ameter
Opens t he M8 par ameter
Opens t he M9 par ameter

Dependent on the
frequency range of
the instrument

GH
MH
KH

HZ

DLF
DFF

DFM

Opens the ∆F par ameter
Opens the ∆F par ameter
Opens the ∆F par ameter

Dependent on the
frequency range of
the instrument

GH
MH
KH

HZ

SDT Opens the st ep s we e p

dwell time parameter

1 ms to 99 sec MS

SEC

SNS Ope ns the st ep s we e p

numb er of steps
parameter

1 to 10,000 SPS

SWT Opens the analog sweep

and CW ram p tim e
parameter

30 ms to 99 sec MS

SEC

LOS Opens the level offset

parameter

+100 dB to –100 dB DB

PDT Opens the power sweep

dwell time parameter

1 ms to 99 sec MS

SEC

PNS Opens the power sweep

numb er of steps
parameter

1 to 10,000 SPS

Table 3-2. Parameter Entry Commands (1 of 2)

67XX GPIB COMMANDS ENTRY COMMANDS

681XXA PM PRELIMINARY 3-7

PROGRAMMING WITH COMPATIBLE PARAMETER AND DATA
67XX GPIB COMMANDS ENTRY COMMANDS

Table 3-2. Parameter Entry Com mands (2 of 2)

MNEMONIC

CODE

FMS Opens the FM sensitivity

SYZ Opens the step-size

UP Increments the open

DN Decrements the open

CLO Closes the previously

T abl e 3-3. Data Entry Commands

MNEMONIC

CODE

0, 1, 2, 3, 4,

5, 6, 7, 8, 9

PARAMETER VALUES TERMINATOR

parameter

parameter for updati ng

parameter by the step size

parameter by the step size

opened paramet er

Numerals for para me ter value entries

–6 MHz/V,
+10 MHz/V, or
+20 MHz/V

Dependent on the
open parameter

N/A N/A

N/A N/A

N/A N/A

DESCRIPTION

KV
MV
GV

N/A

– Change sign of input

. Decimal poin t

CLR Clear data entry

T abl e 3-4. Data Terminator Codes

MNEMONIC

CODE

DB
DM
GH
MH

KH

HZ

SEC

MS

US
GV
MV

KV

PCV
SPS

Decibels (dB)
dBm
GHz
MHz
kHz
Hertz (Hz)
Seconds
Milliseconds (ms)
Microseconds ( µs)
GHz per volt (GHz/V)
MHz per volt (MHz/ V)
kHz per volt (kHz/V)
Percent per volt (%/ V)
Steps

DESCRIPTION

3-8 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE PARAMETER AND DATA
67XX GPIB COMMANDS ENTRY COMMANDS

Using the SYZ
Command

Each 681XXA parameter has an as sociated step size
that can be used to increment or decrement its
value. Parameters that have common units share a
common step size. For example, the frequenc y pa­rameters (F0-F9, M0-M9, and ∆F) have a common
step size as do the power level parameters (L1, L2,
and Level Offset). Other parameter s, suc h as analog
sweep time, have individual step sizes.

To set the step size for a parameter, first send the
command code to open the par ameter, then send the
SYZ command. Now set the step size by sending a
numeric string with the proper terminator. When
the terminator is receive d, the step size is accepted
and the origin al parameter is again ope n for entry.

Figure 3-1 shows how the SYZ command c an be used
to increment a parameter. In this example, the F1
frequenc y parame ter is set to 4 GHz, the step size is
set to 10 MHz, and F1 frequency is incremen ted
three time s by the value of the s tep size.

F1 4 GH SYZ 10 MH UP UP UP

Sets a step size of 10 MHz, ends the step-size entry,
and reopens the F1 parameter.

Opens the step-size parameter for F1.

Sets the F1 Parameter to 4 GHz.

Selects the F1 Parameter and opens it for entry.

Figure 3-1. Using the SYZ (Step Size) Command

Increments F1 from 4.02 GHz to 4.03 GHz.

Increments F1 from 4.01 GHz to 4.02 GHz.

Increments F1 from 4.00 GHz to 4.01 GHz.

681XXA PM PRELIMINARY 3-9

PROGRAMMING WITH COMPATIBLE CW FREQUENCY
67XX GPIB COMMANDS COMMANDS

3-5

CW FREQUENCY
COMMANDS

Table 3-5 lists the CW frequency command mnemonic codes. Th ese
commands call up each of the 20 prese t (or previou sly se t) CW frequen ­cies. Each command cau ses its associated CW freque ncy to be output
and opens that freque ncy ’ s par ameter for data entry.

The command, SQF, ac cesses the preset freque nc ies in sequen tial or­der—tha t is, F0 to F9 and M0 to M9.

Table 3-5. CW Frequency Commands

MNEMONIC

CODE

CF0

CF1

CF2

CF3

CF4

CF5

CF6

CF7

CF8

CF9
CM0

CM1
CM2
CM3
CM4
CM5
CM6
CM7
CM8
CM9

Set CW mode at F 0
Set CW mode at F 1
Set CW mode at F 2
Set CW mode at F 3
Set CW mode at F 4
Set CW mode at F 5
Set CW mode at F 6
Set CW mode at F 7
Set CW mode at F 8
Set CW mode at F 9

Set CW mode at M0
Set CW mode at M1
Set CW mode at M2
Set CW mode at M3
Set CW mode at M4
Set CW mode at M5
Set CW mode at M6
Set CW mode at M7
Set CW mode at M8
Set CW mode at M9

FUNCTION OPENS FOR ENTRY

F0 paramet er
F1 paramet er
F2 paramet er
F3 paramet er
F4 paramet er
F5 paramet er
F6 paramet er
F7 paramet er
F8 paramet er
F9 paramet er

M0 parameter
M1 parameter
M2 parameter
M3 parameter
M4 parameter
M5 parameter
M6 parameter
M7 parameter
M8 parameter
M9 parameter

SQF Scan to the next higher preset

CW frequency.

SQU Scan up to the next higher preset

CW frequency.

SQD Scan down to the next lower

preset CW frequency .

ACW Activat es the cur re nt ly scann ed

frequency as CW.

CW frequency param et er
then selected

CW frequency param et er
then selected

CW frequency param et er
then selected

CW frequency param et er
then selected

3-10 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE ANALOG AND STEP

CF1 CF6 7 GH SQF

Places the 681XXA at the preset (or previously set) CW F1
frequency and opens the F1 parameter for data entry.

Closes the F1 parameter. Places the 681XXA at the
preset (or previously set) CW F6 frequency and opens the F6
parameter for data entry. Sets the F6 frequency to 7 GHz.

Closes the F6 parameter. Places the 681XXA at the
preset (or previously set) CW F7 parameter and opens
the F7 parameter for data entry.

Figure 3-2. Example of a CW Frequency Comma nd Stri n g

67XX GPIB COMMANDS SWEEP COMMANDS

Progr am min g Note: Sweep gene rator response to a SQF command
depends on the state the instrume nt i s in at the time the command is
received . For example, if the 681X XA is in a CW mode of operation
with the cur re nt ou tput fr equ en cy open for entr y, the SQF command
(1) causes the output to change to the next sequential frequency and
(2) opens that frequ enc y’s parameter for data entry. However, if the in­strument is in any other mode of operation, the SQF command causes
it to switch to the last CW frequency that was output and opens that
parameter for data entry.

Figure 3-2 is an example of a CW frequency command strin g.

3-6

ANALOG AND ST EP
SWEEP COMMANDS

681XXA PM PRELIMINARY 3-11

Table 3-6 (page 3-13) lists the analog and step sweep command mne­monic codes. These co mmand s are divid ed into fiv e subclasses and are
described in the following paragraphs.

Sweep Range Seven swee p rang es are available. The SF1 and SF3

commands selec t the sweep rang es of F1-F2 an d F3­F4 respectively; the FUL command selec ts a full
band sweep from the swee p generator’ s low fre ­quency limit to its high fr equ en cy limit.

The DF0, DF1, DF5, and DF6 commands each select
a symmetrical fre que ncy sweep aroun d F0, F1, F5,
and F6 respectively. The width of the sweep is deter­mined by the ∆F frequency parameter.

PROGRAMMING WITH COMPATIBLE ANALOG AND STEP
67XX GPIB COMMANDS SWEEP COMMANDS

Progr amming Examples:

Programming “F1 2 GH F2 8 GH SF1” sets F1 to
2 GHz, F2 to 8 GHz, and implements a F1-F2 fre­quency sweep.

Programming “DLF 6 GH F5 7 GH DF5” sets ∆F to
6 GHz, F5 to 7 GHz, and implements a F5-∆ F fre­quency sweep.

Progr am min g Note:

If the commanded sweep rang e is invalid, a parame­ter erro r (paragraph 3-19) will be generated, and the
output of the sweep gener ator will not be altered.

A swee p rang e is invalid if (1) the sweep start fre­quency is greater than the stop frequency, or (2) the
∆F frequency parameter resu lts in a sweep that is
outside the range of the instrument.

Alternate
Sweep

Sweep
Trigge rin g

Six alternate sweep comman ds are available. If the
681XXA is sweeping when the alternate swe ep com­mand is received, the swee p generator’ s outpu t will
alternate between the commanded sweep an d the
sweep then being executed.

Progr amming Example:

Assume that the 681XXA had been previously pro­grammed and was then execu tin g an F1-F2 sweep .
Programming “AF3” would then activate the F3-F4
sweep and cause it to alternate with the F1-F2
sweep.

Progr am min g Note:

An alternate swee p command will only be recog n ized
when the 681XXA has been programmed to sweep. It
will be ignored at all other times.

Two modes of sweep triggering are available over the
bus—Automatic and Single. The AUT command se-
lects automatic sweep triggering; the EXT command
selects single sweep triggering.

When automatic sweep triggering is selected, the
sweep continu ally sweep s from its start frequen c y
(or power level) to its stop frequen cy (or pow er level)
with optimal retrace time.

3-12 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE ANALOG AND STEP

MNEMONIC

CODE

FUNCTION

OPENS

FOR ENTRY

SF1
SF3
FUL
DF0
DF1
DF5
DF6

Sweep Range

Selects the F1-F2 sweep mode
Selects the F3-F4 sweep mode
Selects the Full Range sweep mode
Selects the F0-∆F sweep mode
Selects the F1-∆F sweep mode
Selects the F5-∆F sweep mode
Selects the F6-∆F sweep mode

None
None
None
None
None
None
None

AFU

AF1

AF3
AD1
AD5
AD6

Alternate Sweep

Selects Full Range alternate sweep
Selects F1-F2 alternate sweep
Selects F3-F4 alternate sweep
Selects F1-∆F alternate sweep
Selects F5-∆F alternate sweep
Selects F6-∆F alternate sweep

None
None
None
None
None
None

AUT
EXT
TRG
TRS
RSS

Sweep T riggering

Selects Auto T rigger
Selects Single Trigger
Triggers a Single Sweep
Triggers a Single Sweep
Resets a Sweep if in progress

None
None
None
None
None

SWP

SSP

MAN

DU1
DU0
TSS

Analog/Step Sweep Selec t

Selects Analog Sweep
Selects Step Sweep
Selects Manual (Step) Sweep
Selects Dual Step Sweep mode
Deselects Dual Step Sweep mode
Steps to next point in DU1 mode

None
None
None
None
None
None

SP1
SP0

Special Step Sweep (Step s Not Equally Space d)

Selects non-equally sp aced step sweep
Deselects non-eq ually spac ed step swe ep

None
None

Table 3-6. Analog and Step Sweep Commands

67XX GPIB COMMANDS SWEEP COMMANDS

When single swe ep trig g er ing is selected, a single
sweep starts when the TRG or TRS command is re-
ceived . Th e RSS comman d resets the sweep to its
start frequenc y (or pow er level), w he ne ver the com­mand is receiv ed while a single swee p is in prog r es s.

681XXA PM PRELIMINARY 3-13

PROGRAMMING WITH COMPATIBLE ANALOG AND STEP
67XX GPIB COMMANDS SWEEP COMMANDS

SF1

Analog/Step
Sweep Select

AUT SWP EXT TRS SSP TRS

Three commands are available—SWP selects an ana­log sweep, SSP selects a step sweep , and MAN se­lects a manual (step) sweep. The selected swee p
mode applies to all sweep ranges. Fig ur e 3-3 shows
an example of a sweep command str ing.

Progr am min g Not es:

Commanding either SWP or SSP does not, by itself,
provid e a swept-fr equ enc y outpu t. It only deter­mines whether the swep t-fr equ en cy outp ut will be
an analog or step sweep. If, on the other hand, a fre­quency sweep is being outpu t by the 681XXA when
one of these commands is received, that sweep will
assume the commanded sweep mode.

The MAN command only provides for setting up the
sweep generator for a manual sweep . It must be ac­companied by the RL command to return the ins tru­ment to local (front panel) control in order for the
operator to perfor m the man ual swe ep.

Selects ANALOG sweep.

Selects AUTO triggering.

Selects the F1-F2 sweep range.

Figure 3-3. Example of a Sweep Command String

Triggers a single sweep.

Selects step sweep.

Triggers a single sweep.

Selects the External/Single triggering mode.

3-14 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE ANALOG AND STEP
67XX GPIB COMMANDS SWEEP COMMANDS

Dual Step Sweep Mode

The dual step sweep mode provide s for gene ratin g
synchronized, step sweep outputs from two 681XXAs
at a frequency offset. Fig ure 3-4 shows an example
of dual step sweep programming.

10 ! "DUAL"
20 CLEAR
30 DISP "ENTER # OF STEPS"
40 INPUT S
50 DISP "ENTER WAIT TIME [mS]
60 INPUT W
70 WAIT 100
80 DISP "ENTER ’LO’ START FREQ [GHz]"
90 INPUT F1
100 DISP "ENTER ’LO’ STOP FREQ [GHz]
110 INPUT F2
120 DISP "ENTER OFFSET [GHz]
130 INPUT F3
140 !
150 ! Initialize both 681XXA’s
160 !
170 OUTPUT 705 ;"CF1F1";F1;"GHF2";F2;
"GHSNS";S;"SPSSSPEXTCLO"
180 OUTPUT 706 ;"CF1F1";F1+F3;"GHF2";
F2+F3;"GHSNS";S;"SPSSSPEXTCLO"
190 WAIT 1000
200 !
210 ! Set both to dual mode and enable
GET to end DWELL
220 !
230 SEND 7 ; CMD "%&" DATA "GTLDU1SF1"
EOL
240 WAIT 100
250 ! Trigger the sweep and wait for
retrace to finish
260 SEND 7 ; CMD "%&" DATA "TRS" EOL
270 WAIT 100
280 ! Listen address both 681XXA’s
290 SEND 7 ; CMD "%&"
300 FOR C+1 TO S+1
310 WAIT W
320 ! Trigger both to next point
330 TRIGGER 7
340 NEXT C
350 GOTO 260

Figure 3-4. Dual Step Sweep Program ming Exa mp le

681XXA PM PRELIMINARY 3-15

PROGRAMMING WITH COMPATIBLE FREQUENCY
67XX GPIB COMMANDS MARKER COMMANDS

Special Step
Sweep

For this example , assum e a freq uenc y sweep of 3 GHz to 10 GHz, with steps at 3,
6, 8, 9, and 10 GHz.

Sample Coding in BASIC

10 OUTPUT 705; "ZL000 3GH 6GH 8GH 9GH 10GH ZEL"
20 OUTPUT 705; "F1 3GH F2 10GH SNS 4SPS"
30 OUTPUT 705; "SP1 SSP SF1"

This special step sweep pro vid es for a step sweep
that has non-equally spaced steps. It can be used in
any of the available sweep ranges (F1-F 2, F3-F4,
Full, F0-∆F, F1-∆F, F5-∆F, and F6-∆F). The start fre-
quency in this sweep mu st be equal to the first fre­quency progr ammed wi th the ZL(X
(Table 3-15). The intermediate steps can be pro­grammed to be any frequenc y within the range of
the programme d sweep .

Progr am min g Note:

The SP1 command can be used wi th the dual step
sweep mode.

Figure 3-5 shows an example of special step sweep
programming.

000-999

) command

3-7

FREQUENCY MARKE R
COMMANDS

Explanation of Code

Line 10 sets up the step frequencies .
Line 20 sets star t and stop f re quen cies and number of step s (frequen cy point s – 1).
Line 30 set the sweep generator to SP1, Step Sweep, and F1-F2 swe ep range.

Figure 3-5. Special Step Sweep Programmin g Example

Table 3-7 lists the frequency marke r command mnemonic codes. These
commands provide for (1) selectin g a CW frequency as a potential
marker, (2) selecting a potential marke r as an active mark er, and (3) in ­dividually tur n ing markers on and off.

The ME1 command will enable a marker at the current frequen c y that
is open for upda te; the ME 0 command will disable the same marker. If
a frequency par ameter is not open, no action will be taken. The IM1
and VM1 comman ds will turn on their resp ec tive inte nsity and video
marke rs. The MK0 command will turn all markers off.

Figure 3-6 shows an examp le of a frequen c y marker co mmand string.

3-16 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE FREQUENCY
67XX GPIB COMMANDS MARKER COMMANDS

Table 3-7. Frequency Marker Commands

MNEMONIC

CODE

ME1 Enables a marker at the active frequency

ME0 Disables the marker at the active fre quen cy None
MK0 Turns off markers. Enabled markers remain

IM1 Tur ns on the intensity marker mode None

VM1 Turns on the video mark er mode None

Progr am min g Note: Only one marker mode can be active. Conse­quently, if the intensity marker mode is active and the video marker
mode is programmed, the displayed markers will change to video mark­ers. Either mode can be turned off with the MK0 command.

VM1 F1 ME0 F7 ME1 F4 ME1 MK0

FUNCTION

(F0-F9 or M0-M9)

enabled, but are not active

OPENS

FOR ENTRY

None

None

Turns both markers off, but leaves the F7 and F4 markers
enabled. Therefore, when IM1 or VM1 is next programmed,
two frequency markers will reappear on the display — provided
their frequencies are within the 681XXA's sweep range.

Enables the F4 frequency marker.

Enables the F7 frequency marker.

Disables the F1 frequency marker.

Turns on the video-marker mode, and turns off the
intensity-marker mode (if previously enabled).

Figure 3-6. Example of a Frequency Marker Command String

681XXA PM PRELIMINARY 3-17

PROGRAMMING WITH COMPATIBLE MODULATION
67XX GPIB COMMANDS COMMANDS

3-8

MODULATION
COMMANDS

Table 3-8 lists the modulation command mnemon ic codes. These com­mands provide fo r AM, FM, and squ are wave/ pu lse modu l ation of the
sweep generator’s output signal.

NOTE

During remote operation of the 681XXA via the GPIB, all
external AM, FM, and square wave/pulse modulating signals
must be input to the front panel connectors.

Amplitude
Modulation

Frequency
Modulation

Two AM modes are available—Linear an d Log. The
AM1 command turns on the external AM function in
Linear mode (100%/V sen sitiv ity) . The AM2 com ­mand turns on the exter nal AM fu nction in Log
mode (10 dB/V sensitivi ty). The AM 0 command turns
off the exter n al AM fun ction .

Two FM modes are available—Narrow and Wi d e.
The FM1 (or FMU) command turns on the external
FM function in Narro w mode . Narrow FM mode al­lows maximum deviation s of 50 MHz. The FMW com­mand turns on the exter nal FM func tion in W ide
mode. Wide FM mode allows maximum deviations of
100 MHz. The FM0 command turns off the external
FM function. In both Narro w and W i d e FM modes,
the 681XXA output signal is not phase locked to fa­cilitate greater FM deviations.

Square Wave
Modulation

Progr am min g Note:

When an FMS (FM sensitivity) parameter entry is
made, one of three FM sensitivities will be selec ted
depending on the input.

For a parameter entry of <0 MHz/V, the FM
sensitivity will be set to –6 MHz/V.
For a parameter entry of 0 to <15 MHz/V, the
FM sensitivity will be set to +10 MHz/V.
For a parameter entry of ≥1 5 MH z/ V, the FM
sensitivity will be set to +20 MHz/V.

Two square wave modulation modes are available—
Internal and External. In internal mode, square
wave modulation of the output signal by one of four
modulating signals is available using the following
commands:

SW1 turns on modulation at 400 Hz.
SW2 (or SQP) turns on modulation at 1 kHz.
SW3 turns on modulation at 7.8125 kHz.
SW4 turns on modulation at 27.8 kHz.

3-18 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE MODULATION

MNEMONIC

CODE

FUNCTION

AM0 T ur ns off the exter nal AM funct ion. (T his is t he de fa ult m od e. )
AM1 T ur ns on the exter nal AM funct ion in Line ar mode. (Front pa nel

exte r na l AM in pu t at 6 00 Ω impedance.)

AM2 T ur ns on the ext ernal AM function in Log mode. ( Fro nt pane l

exte r na l AM in pu t at 6 00 Ω impedance.)

FM0 Tur ns off the external FM funct ion an d re- est ab lish es pha se

lock. (This is the default mode. )

FM1 Tur ns on the ex te rna l FM funct ion in Nar row m od e. The sweep

generator outp ut is not phase- locke d. (Front pane l exte rna l FM
input at 600Ω impedanc e. )

FMW Turns on the externa l FM funct ion in W id e mode. Th e swee p

generator outp ut is not phase- locke d. (Front pane l exte rna l FM
input at 600Ω impedanc e. )

FMU Same as FM1. T ur ns on t he ex te rna l FM func tion in Narro w

mode. The sweep generator output is not phase-lo cked. (Front
panel external FM input at 600Ω impedance.)

P0 Turns off the sq uar e wave/ pu lse modulat ion m ode.
SQP Turns on internal squa re wave modulat ion at 1 kHz.
SW0 Same as P0. Turns of f the squar e wa v e/pulse m od ulat io n

mode.
SW1 Turns on internal squa re wave mo dulat ion at 400 Hz.
SW2 Same as SQP. Tur ns on inter nal squ are wave mod ulat io n at

1 kHz.
SW3 Turns on internal square wave mo dulat ion at 7. 8125 kHz.
SW4 Turns on internal squa re wave mo dulat ion at 27. 8 kHz.

XP Tur ns on the ex te rna l squar e wave/ pu lse mo dulat ion mode.

(Front panel exter nal squ are wave/ pulse input .)

Table 3-8. Modulation Com mands

67XX GPIB COMMANDS COMMANDS

The XP comman d turns on the external square
wave/pulse modulation mode. Both the SW0 and P0
commands turn off the squar e wave modu lation
mode.

681XXA PM PRELIMINARY 3-19

PROGRAMMING WITH COMPATIBLE OUTPUT POWER
67XX GPIB COMMANDS LEVELING COMMANDS

3-9

OUTPUT POWER
LEVELING COMMANDS

Table 3-9 lists the outpu t power levelin g command mne mon ic codes.
These commands provide (1) for turning the power leveling off or (2) for
leveling the output power using any of the following:

The internal leveling detector.
An external detector conn ec ted to the front pane l EX TERNAL ALC
IN connector.
An external pow er meter con ne cted to the front panel EXTERNAL
ALC IN connecto r.

Figure 3-7 shows an examp le of a output power lev el command s tring .

Table 3-9. Power Leve li n g C om mands (1 of 2)

MNEMONIC

CODE

L1 Selects the L1 power level value as the R F

output power level.
Deselects the L2 parameter, if previously
programmed.

L2 Selects the L2 power level value as the R F

output power level.
Deselects the L1 parameter, if previously
programmed.

FUNCTION

OPENS

FOR ENTRY

L1

L2

RF1 Turn s on the RF output. (This is the def ault

mode.)
RF0 Turns off the RF out p ut. None
LO1 Turn s on t he Lev el Of f set funct ion. The value of

the Level Of f set parameter is added to the le vel

measured by the inte rna l leveling loop. Th e

resultant power level value is display ed.
LO0 Turn s of f t he Lev el Of f set funct ion. None

IL1 Select s inter nal leveling of the output power.

(This is the default mode. )

Deselects the DL1 or PL1 leveling m odes , if

previously programmed.
DL1 Selects external leveling of the output power ,

using a signal from an external det ec to r

connected to the front panel EXTERNAL ALC

IN connector.

Deselects the IL1 or PL1 level ing modes, if

previously programmed.

None

None

None

None

3-20 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE OUTPUT POWER
67XX GPIB COMMANDS LEVELING COMMANDS

T abl e 3-9. Power Leveling Comm and s (2 of 2)

MNEMONIC

CODE

PL1 Selects external leveling of the output power

using a signal from an exte rna l power m eter
connected to the front pan el EXTERNAL ALC
IN connnector.
Deselects the IL1 and DL1leveling m ode s, if
previously progra mmed .

LV0 Turns off leveling of the output power. None

LSP Selects the Power Sweep mode. Th e power

level will sweep as determined by the preset (or
previously set) dwell- time and number -of- st eps
param eters.

EG1 Provides for entering a value for the ext ern al-

level gain DAC.

EG0 Outputs the value of the exter nal-lev el gain

DAC.

FUNCTION

OPENS

FOR ENTRY

None

None

None

None

RF0 L1 2 DM L2 12 DM PNS 10 SPS LSP RF1

Selects a power sweep and 10 steps.

Selects Level 2 and sets it for 12 dBm.

Selects Level 1 and sets it for 2 dBm.

Turns the RF output off.

Figure 3-7. Example of an Output Power Level Comm and String

Turns the RF output on.

Selects a level sweep.

681XXA PM PRELIMINARY 3-21

PROGRAMMING WITH COMPATIBLE OUTPUT
67XX GPIB COMMANDS COMMANDS

3-10

OUTPUT COMMANDS

Table 3-10 lists the outpu t command mne mon ic codes. These com­mands provide for the ou tput of data from the sweep g en era tor to the
controller. Figure 3-8 (pag e 3-24) shows examp les of outpu t comman d
programming.

Table 3-10. Output Commands (1 of 2)

MNEMONIC

CODE

OI Causes the sweep gene rator to identify it self by sending th e

followin g param et er infor ma tion over the bus; mo del num ber,
low-end frequency, high-end frequency, minimum output power
level, maximum outp ut power lev el, so ftwar e revision num be r,
serial number, model prefix (A or B), and series (1 or 2). This
command can be us ed to send para me ter inf ormat ion to t he
controller automa tica lly, thus relieving the opera to r from hav ing
to input the info rmat ion manua lly. The string is 34 characters
long.

OFL Returns the low-end freq uenc y value (in MHz) to the contro ller.

OFH Ret ur ns the high- end freque ncy va lu e (in MHz) t o the

controller .

OF0 Returns the F0 frequen cy value (in MHz) to the cont ro ller.

FUNCTION

OF1 Returns the F1 frequen cy value (in MHz) to the cont ro ller.
OF2 Returns the F2 frequen cy value (in MHz) to the cont ro ller.
OF3 Returns the F3 frequen cy value (in MHz) to the cont ro ller.
OF4 Returns the F4 frequen cy value (in MHz) to the cont ro ller.
OF5 Returns the F5 frequen cy value (in MHz) to the cont ro ller.
OF6 Returns the F6 frequen cy value (in MHz) to the cont ro ller.
OF7 Returns the F7 frequen cy value (in MHz) to the cont ro ller.
OF8 Returns the F8 frequen cy value (in MHz) to the cont ro ller.

OF9 Returns the F9 frequen cy value (in MHz) to the cont ro ller.
OM0 Returns the M0 frequency value (in M Hz) to the cont roller.
OM1 Returns the M1 frequency value (in M Hz) to the cont roller.
OM2 Returns the M2 frequency value (in M Hz) to the cont roller.
OM3 Returns the M3 frequency value (in M Hz) to the cont roller.
OM4 Returns the M4 frequency value (in M Hz) to the cont roller.

3-22 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE OUTPUT

MNEMONIC

CODE

FUNCTION

OM5 Retur ns the M 5 freq uenc y value ( in MHz) to the cont ro ller.
OM6 Retur ns the M 6 freq uenc y value ( in MHz) to the cont ro ller.
OM7 Retur ns the M 7 freq uenc y value ( in MHz) to the cont ro ller.
OM8 Retur ns the M 8 freq uenc y value ( in MHz) to the cont ro ller.
OM9 Retur ns the M 9 freq uenc y value ( in MHz) to the cont ro ller.

OL1 Returns the L1 power value (in dBm) to the cont roller.

OL2 Returns the L2 power value (in dBm) to the cont roller.
OLO Returns t he Le vel Of f set powe r value (in dB) to the con troller.
ODF

Returns the ∆F fre quen cy value (in MHz) to the cont ro lle r .

OPD Ret urns t he dwe ll time of the powe r sweep (in ms) to th e

controller.

OPS Returns the nu mb er-of -ste ps of the power sweep to the

controller.

OSD Ret ur ns the d we ll t ime of t he step s we ep (in m s) to the

controller.

OSS Returns the number- of-ste ps of the step sweep to the

controller.
OST Returns the sweep t ime va lue (in m s) to the con troller.
OVN Ret urns t he RO M ver sion num be r to the cont r ol ler.

OWT Returns the GPI B terminat ion st at us to the con troller. (0=CR;

1=CRLF)
OSE Returns t he last G PI B synt ax er ro r to th e cont r o lle r .

OEM Returns the Extended SRQ M ask by tes (3 binary byte s) to the

controller.
OES Returns the G PI B Sta tus byt es (3 binar y bytes) to the

controller.
OSB Returns the Primary GPIB Status byte to the controller.

OSM Returns the Primary SRQ Mask byte to the controller.

OSR Ret urns t he se lf-te st results (6 binar y bytes) to the contro ller.

Table 3-10. Output C o mmands (2 of 2)

67XX GPIB COMMANDS COMMANDS

681XXA PM PRELIMINARY 3-23

PROGRAMMING WITH COMPATIBLE STORED SETUP
67XX GPIB COMMANDS COMMANDS

760 OUTPUT 705;"OF1"
770 ENTER 705;A
780 PRINT "F1 is set at ";A;" MHz"

1050 OUTPUT 705;"OSS"
1060 ENTER 705;A
1070 PRINT "Step Sweep has ";A;" Steps"

Figure 3-8. Output Command Progra mmi ng Exam ple s

3-11

STORED SE TUP
COMMANDS

Table 3-11 lists the stored setup command mnemonic codes. These com­mands provide for savin g instru men t setups and recallin g them for use.

A cur ren t instru men t setup can be saved to internal se tup memory us­ing the SSN(M
to nine instrumen t setups can be stored in this mann er. The command

RSN(M

memory location s 1 to 9.
If more than nine ins trumen t setups are ne eded , or if it is desirable to

store the setups in the controller instead of the sweep gene rator mem­ory, the 681XXA can be commanded to outpu t and accept stor ed setups
over the bus.

The SAF command outputs the current instrument setup to the control-
ler in a 300-byte (approximately) binary data string. The controller
stores the instrument setup. The RCF command readies the swe ep gen­erator to receiv e a new instrumen t setu p recalle d fro m the contr oller.
Figure 3-9 shows an examp le of SAF and RCF command programming.

The SAM and RCM comman ds perform the same func tions as described
for the SAF and RCF commands, except that all of the stored ins tru­ment setups are includ ed in the binary data string along with the cur­rent instrumen t setup. For these comman ds, the binar y data string is
approximately 3000 bytes long.

) recalls a stored instrument setup from inter n al setup

1 to 9

) command, where M = memory locations 1 to 9. Up

1 to 9

3-24 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE STORED SETUP

MNEMONIC

CODE

FUNCTION

SAF Outputs the cur re nt instrum ent set up to the co ntroller.

SAM Out put s both t he cu rrent inst rumen t setu p and all store d

instrume n t setu ps t o th e cont ro l ler.

SM Recalls the next stored instrument set up in seq uenc e.

SSN(M

1-9

) Saves the current instru me nt set up to inte rna l setu p memo ry

location M, whe re M = 1 to 9.
RCF Readies the 681XXA to receive a new instrument setup

recalled from the control ler.

RCM Readies the 681XXA to receive a new instrument setup and

new stored setu p s reca l led from the cont r o lle r .

RSN(M

1-9

) Recalls the instrume nt setup st ored in in te rna l setu p memo ry

location M, whe re M = 1 to 9.

Table 3-11. Stored Setup Commands

10 DIM A$ [300]
20 OUTPUT 705; "SAF"
30 ENTER 705 USING "#%, #%K"; A$ (Requires EOI
to be the terminator of the read.)
40 OUTPUT 705; "RCF"; A$ (A$ must follow the SAF.)

Figure 3-9. SAF and RCF Command s Pro gra mmi ng Exam p le

67XX GPIB COMMANDS COMMANDS

Progr am min g Note: The SAF and SAM commands output binar y
data. The data string is termina ted with “ EO I” on the last byte sent
(no CR or LF is sent).

681XXA PM PRELIMINARY 3-25

PROGRAMMING WITH COMPATIBLE SRQ AND STATUS
67XX GPIB COMMANDS BYTE COMMANDS

3-12

SRQ AND ST A T US
BYTE COMMANDS

Table 3-12 (page 3-28) lists the Service Request (SRQ) and Status Byte
command mnemonic codes. These commands enable the sweep gener­ator to request service from the controller when certain, predefined con­ditions ex ist.

Status Bytes The 681XXA h a s three GPIB s tatus by tes—th e p ri-

mary and two extended status bytes. Figu re 3-10
shows the three statu s by tes an d identifies the
status reporting fu nction of each status byte bit.

Each status reporting bi t, with the excep tion of pri­mary status byte bit 6 (SRQ), is set when the condi­tion on which i t repor ts is detec te d. Th ese ch an g e s
in status byte bit settings can be read by the contr ol­ler as follows:

The contents of the primary status byte is re­turned to the contr oller in re spon se to a serial
poll or the OSB command.
The contents of the primar y status byte and
the two extended status bytes are returned t o
the controller in response to the OES com­mand. Figure 3-11 (page 3-29) shows an exam­ple of OES command programming.

SRQ
Generation

The sweep gen er a tor can g ener a te GPIB ser vice r e­quests (SRQs) to report instrument status and syn­tax errors to the controller. The sweep g ener a tor will
generate an SRQ if:

1. Th e SRQ ge ne ration fu nc tion has been enabled us­ing the SQ1 command and,

2. O ne (or more) of the status reporting function s is
true an d ,

3. Th e pr imary status byte bit associated with the
true status reportin g func tio n has been enabled.

Bits in the primary status byte can be enabled by
either of two methods. Th e fir st uses the FB1/F B0,

ES1/ES0, UL1/UL0, LE1/LE0, PE1/PE0, SE1/SE0, and
SB1/SB0 commands, described in Table 3-12, to indi-

vidually enable or disable each bit. The second
method uses a single 8-bit status byte mask (MB0) to
enable any or all of the primary status byte bits.

Figure 3-12 (page 3-30) show s examples of status
byte mask programming .

3-26 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE SRQ AND STATUS

NOTE

All status byte bits are latched except for those indicated with the “*”. Once
set, an OES or OSB comman d must be received before the co nditio n will
be reset. The primary status byte bit 6 (SRQ) is cleared by a serial poll
only.

Primary status byte bit 0 is set whenever one of the stat us condition s rep orted
by an extended st atus by te 1 is true and the as sociat ed status bit is enabled.
This bit is cleared when the controller send s the OES com mand.

Primary status byte bit 7 is set whenever one of the stat us condition s rep orted
by an extended st atus by te 2 is true and the as sociat ed status bit is enabled.
This bit is cleared when the controller send s the OES com mand.

Primary status by te bit 6 (SRQ) is not maskable. This bit is set by the SQ 1 c om­mand and cleared by a serial poll.

Extended stat us byte 1 bits are enabled by the extende d stat us byte 1 mask
command, MB1.

Extended stat us byte 1 bit 0 (SelfTest Failed) and bit 2 (Self Test Complete)
should not be unma sked at the same time.

Extended stat us byte 2 bits are enabled by the extende d stat us byte 2 mask
command, MB2.

The setting of extende d st atus byte 2 bit 4 (RF Unlocked) is blocked or un­blocked by the comma nds, EL0 an d EL1 (See Table 3-12).

Extended stat us byte 2 bit 7 (Para me ter Chan ged) is only used with t he Model
562 interface . The set t ing of this bit is blocked or unblocked by the commands,
II0 and II1 (See Table 3-12).

Figure 3-10. Primary and Exten ded Status Bytes

Extended

Status
Byte 2

SRQ Syntax

Error

Parameter

Range

Error

Lock

ErrorRFUnleveled

End

of

Sweep

Extended

Status
Byte 1

Bit 7

(128)

Bit 6

(64)

Bit 5

(32)

Bit 4

(16)

Bit 3

(8)

Bit 2

(4)

Bit 1

(2)

Bit 0

(1)

Primary Status B yte

Not

Used

Not

Used

Not

Used

External*

Fine Loop

in Use

Not

Used

Self Test

Completed

Modulation

Range

Error

Self Test

Failed

Bit 7

(128)

Bit 6

(64)

Bit 5

(32)

Bit 4

(16)

Bit 3

(8)

Bit 2

(4)

Bit 1

(2)

Bit 0

(1)

Extended Status Byte 1

Parameter*

Changed

Calibrate
Function

Finished

Analog
Sweep

Lock Error

RF*

Unlocked

Crystal

Oven

Failure

Calibrate

Function

Failed

Modulation

Measrmnt

Complete

Power

Measrmnt

Complete

Bit 7

(128)

Bit 6

(64)

Bit 5

(32)

Bit 4

(16)

Bit 3

(8)

Bit 2

(4)

Bit 1

(2)

Bit 0

(1)

Extended Status Byte 2

67XX GPIB COMMANDS BYTE COMMANDS

681XXA PM PRELIMINARY 3-27

PROGRAMMING WITH COMPATIBLE SRQ AND STATUS
67XX GPIB COMMANDS BYTE COMMANDS

Table 3-12. SRQ and Status Byte Commands (1 of 2)

MNEMONIC

CODE

ES1 Enables an SRQ to be gene rated when Prim ar y Statu s Byt e bit

1 (End of Sweep) is set an d SQ 1 has be en pr ogr am me d.

ES0 Inhibits an SRQ from being gener ated when the End of Sweep

bit is set. This is the def ault mode.

FB1 Enables an SRQ to be generat ed when Prim ar y Statu s Byt e bit

0 (Extended Status Byte 1) is set and SQ1 ha s been
programme d. The Extend ed St at us Byt e 1 bit is set whenever
one (or more) of the unmasked sta tus rep orting f unc tion s in
Extended St at us Byt e 1 is true.

FB0 Inhibits an SRQ from being generat ed when the Extended

Status Byte 1 bit is set. This is the d ef ault mo de.

LE1 Enables an SRQ to be generated when Prim ary Sta tu s Byte bit

3 (Lock Error ) is set and SQ1 has b ee n pro gra mm e d .

LE0 Inhibits an SRQ from being gener ated when the Lock Er ror bit

is set. This is the defa u lt mode .

MB0 Sets an 8-bit data ma sk that is used to ena ble spec ific bit s of

the Primary Statu s Byt e (Figure 3-xx) . This enab les any or all
of the bits (except fo r bit 6) in the Primary Status Byte to
generate an SRQ using one 8-bit byt e. This co mma n d can be
equivalent to sending ES1, FB1, LE1, PE1, SE1, SB1, and
UL1.

FUNCTION

MB1 Sets the enable mask byt e for Extended Stat us Byte 1.
MB2 Sets the enable mask byt e for Extended Stat us Byte 2.

PE1 Enables an SRQ to be gene rated when Prim ar y Statu s Byt e bit

4 (Parameter Range Error) is set and SQ1 has been
program med.

PE0 Inhibits an SRQ from being gener ated when the Paramet er

Range Error bit is set. This is the default mode.

SB1 Enables an SRQ to be gene rated when Prim ar y Statu s Byt e bit

7 (Extended Status Byte 2) is set and SQ1 ha s been
programme d. The Extend ed St at us Byt e 2 bit is set whenever
one (or more) of the unmasked sta tus rep orting f unc tion s in
Extended St at us Byt e 2 is true.

SB0 Inhibits an SRQ from being gener ated when the Extended

Status Byte 2 bit is set. This is the d ef ault mo de.

3-28 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE SRQ AND STATUS

MNEMONIC

CODE

FUNCTION

SE1 Enables an SRQ to be genera te d when Prim ary St at us Byte

bit 5 (Syntax Error) is set and SQ 1 has been pr ogr am med.

SE0 Inhibits an SRQ from being gener ated w he n the Synt ax Er ror

bit is set. Th is is t h e default mode.

SQ1 Enables the SRQ generation func tion . This comm and a llows a

status reporting funct ion, that is true and enabled , to pull the
SRQ line LOW (true ) and requ est ser vice from the con troller.

SQ0 Disables the SRQ generat ion funct ion. This is t he default

mode.

UL1 Enables an SRQ to be generate d when Prim ary St at us Byte

bit 2 (RF Unleveled) is set and SQ1 has be en pr ogr amme d.

UL0 Inhibits an SRQ from being generated whe n the RF Unleveled

bit is set. Th is is t h e default mode.

EL1 Unblocks updating of th e Extende d Sta tu s Byt e 2 bit 4 (RF

Unlocked).

EL0 Blocks updating of the Extended Status Byt e 2 bit 4. This is

the default se tting b e caus e it is norma l for the RF to be
momentari ly unlocke d dur ing sweep s and sweep re trace .

II1 Unblocks updat ing of th e Extende d Sta tu s Byt e 2 bit 7

(Paramete r Changed) . This bit is only us ed with th e Model 56 2
interface. This bit is cleared when the 562 s ends the O CP
command (Output Last Paramet er Chang ed).

II0 Disables updating of the Exten ded St atus Byt e2 bit 7. This is

the default se tting.

CSB Clears all GPIB status bytes.

Table 3-12. SRQ and Status Byte Command s (2 of 2)

67XX GPIB COMMANDS BYTE COMMANDS

OUTPUT 705; "OES"
ENTER 705 USING "#, B"; A, B, C
MAIN = A
1 EXT = B
2 EXT = C

Figure 3-11. OES Command Program ming Exa mp le

681XXA PM PRELIMINARY 3-29

PROGRAMMING WITH COMPATIBLE SRQ AND STATUS
67XX GPIB COMMANDS BYTE COMMANDS

The 681XX A has a software mask that perm its manipu la tion of the thr ee stat us by te s over th e bus. This man ip ulat io n is ac­complished by sending the comma nd cod es MB0, MB1, MB2, or all three at once, followed by an argument that assigns an
on/off con dition for each bit in the byte. Two examples are shown be lo w:

EXTENDED STATUS BYTE 1

SELF TEST FAILED

MODULATION RANGE ERROR

SELF TEST COMPLETE

0
1
2
3

"1"

"2"

EXTERNAL FINE LOOP IN USE

MASK BYTE 1

EXAMPLE #1

1
0
0

0
1

0
0
0

EXAMPLE #2

0
1
0

0
1

0
0
0

4
5

6
7

0
1
2

3
4

5
6
7

"4"

"8"

"16"

"32"

"64"

"128"

OR

PRIMARY

STATUS

BYTE

BIT 0

EXAMPLE #1: "MB1" (CHR $(17))

Sets bits 0 and 4 in Mask Byte 1 to 1 and all other bits to 0, thus enabling bits 0 and 4 in Extended Status Byte 1 to be
read from the bit 0 position of the Prim ar y Statu s Byt e.

EXAMPLE #2: "MB1" (CHR $(18))

Sets bits 1 and 4 in Mask Byte 1 to 1 and all other bits to 0, thus enabling bits 1 and 4 in Extended Status Byte 1 to be
read from the bit 0 position of the Prim ar y Statu s Byt e.

Figure 3-12. Status Byte Mask Programming Exa mples

3-30 PRELIMINARY 681XXA PM

MNEMONIC

CODE

FUNCTION

BPN Selects a –5V level for the retrace and bandswitch blanking

outputs. (T he retr ace blanking ou tp ut sig nal is available at th e
rear panel RETRACE BLANK OUT connector and pin 6 of the
AUX I/O connector; the bandswit ch blan king outpu t signal at
pin 20 of the AUX I/O connector.)

BPP Selects a +5V level for the retrace and bands witch blanking

outputs.

EP0 Selects TTL-low to turn RF on during squ are wave/pu ls e

modulation.

EP1 Selects TTL-high to turn RF on during s quar e wave/ pulse

modulation.

PP0 Selects normally-op en con ta cts on the int ern al penlift re lay.

(The penlift relay outpu t, availab le at the rear pane l PEN LIFT

OUT connect or, is used to lift a plotter pen dur ing re trace .)
PP1 Selects normally-clos ed con ta cts on the int ern al penlift re lay.
RC0 Selects RF to be off during frequency swit ching in CW and

step sweep modes.
RC1 Selects RF to be on during frequency switching in CW and

step sweep modes.

RT0 Selects RF to be off during retrace.
RT1 Selects RF to be on du ring r etrac e.

Table 3-13. Configur atio n Com ma nds

PROGRAMMING WITH COMPATIBLE CONFIGURATION
67XX GPIB COMMANDS COMMANDS

3-13

CONFIGURATION
COMMANDS

Table 3-13 lists the configuration co mmand mnemonic codes. These
commands permit selection of the follow in g system con fig uration items
via the bus:

A +5V or –5V level for the re ar pan el retrace and bandswitch
blanking outputs.
A TTL-low or TTL-high sig n al tu rn on of RF du r ing squ are
wave/pulse modu ation.
Normally-o pen or normally- clo se d contac ts on the inter nal penlif t
relay.
RF on or RF off during frequen c y switch ing in CW and step
sweep modes.
RF on or RF off during sweep retrace.

The system config uration selection s mad e with GPIB comman ds re­main in effect when the ins trumen t is retur ned to local con tr ol.

681XXA PM PRELIMINARY 3-31

PROGRAMMING WITH COMPATIBLE GROUP EXECUTE
67XX GPIB COMMANDS TRIGGER COMMANDS

3-14

GROUP EXECUTE
TRIGGER COMMANDS

Table 3-14 lists the grou p execute trigger (GET) command mne mon ic
codes. These comman ds let a GET bus message (Table 1-3) be used to
trigger cer tain swee p gen er ator functions and thus speed up bus opera­tions.

In the default state, the 681XXA respond s to a GET message by trigger­ing a single sweep.

Table 3-14 . Group Execute Trigger Commands

MNEMONIC

CODE

GTC Configures the 681XXA to execute an SQF command (scan to

the next higher pres et CW f req uenc y) each time a GE T
message is received .

GTD Configures the 681XXA to execute a DN command (steps the

open paramet er down by the st ep size) each t ime a GET
message is received .

GTF Configures the 681XXA to exe cute a fast-fr eque ncy- swit ching

step (Table 3-15) each time a GE T message is received.

GTL Configures the 681XXA to execute a TSS command (ste ps to

the next point in a dual step sweep mode) each time a GET
message is received .

FUNCTION

GTO Disables the GET functions.

GTS Configures the 681XXA to exe cute a TRS comman d (trigger a

single sweep) each time a GET mes sage is received. This is
the defa ult m od e .

GTT Configures the 681XXA to execute a TST com mand (exec ute

a complete signal gene rator self test) each time a GE T
message is received .

GTU Configures the 681XXA to execute a UP command (steps the

open parameter up by the step size) each time a GE T
message is received .

Y Sending a “Y” is equivalent to sending a GET.

3-32 PRELIMINARY 681XXA PM

MNEMONIC

CODE

FUNCTION

ZL(X

000-999

) Loads a CW frequency into the stack at location X. Th e

location is a number from 000 to 999.

ZEL Ends frequency loading.

ZS(X

000-999

) Sets the stack pointer to point to location X. The locat ion is a

number from 000 t o 999.

Table 3-15. Fast-Frequency-Switching Commands

OUTPUT 705; “ZL000” . . . Set pointer for load
OUTPUT 705; “10 GH, 11 GH, 12 GH, 13 GH”
OUTPUT 705; “ZEL GTF”
NEW
OUTPUT 705; “ZS000” . . . Set pointer to start

TRIGGER 705; . . . . Sets 10 GHz

TRIGGER 705; . . . . Sets 11 GHz

TRIGGER 705; . . . . Sets 12 GHz

TRIGGER 705; . . . . Sets 13 GHz

Figure 3-13. Fast-Frequency-Switching Programming Example

PROGRAMMING WITH COMPATIBLE FAST-FREQUENCY­67XX GPIB COMMANDS SWITCHING COMMANDS

3-15

FAST-FREQUENCY­SWITCHING
COMMANDS

Table 3-15 lists the fast-frequency-switching command mnemonic
codes. These comman ds pr ovide for red ucin g the time that it takes to
switch betwe en two CW frequ en c ies.

In the fast-frequen cy -switc h ing mode, up to 1000 frequenc ies can be
loaded into a stack. A stack pointer can then be se t to point to a specific
frequenc y on the stack and the sweep gen er ator comman ded to switch
from that frequ enc y throu g h the follow in g s tack frequen c ies to the bot­tom of the stack. Figure 3-13 provides an ex ample of fast-frequ en c y­switching programming.

681XXA PM PRELIMINARY 3-33

PROGRAMMING WITH COMPATIBLE POWER-OFFSET­67XX GPIB COMMANDS TABLE COMMANDS

3-16

POWER-OFFSET­TABLE COMMANDS

Table 3-16 list the power-offset-table command mnemonic codes. These
commands provide for maintain ing a consi stent pow er level at a point
within a test setup across the measureme nt frequ en cie s. This “fl atten­ing” of the test point power level is accomplished by summing a power
offset word (from the power off set table) with the swee p generator’ s
normal power leve l DAC word at each freque ncy poin t.

The power-offset mode works in conjunction with the fast-frequency­switchin g mode (par agr aph 3-14). The frequ en cy stack mus t be loaded
before loading the power - offset table because the frequ en cy loadin g
sets the upper limit for the number of entries in the power-o ffset table.
The same pointer is used for both the frequ en cy stack and the powe r­offset table. Once the power-offset table is loaded, the PT 1 command
turns on the pow er- offset mode; the PT0 command turns it off.

Loading the
Power-Offset
Table

To load the power-o ffset table, use the comman d,

PTL clch dldh. ...., where “clch” is the number of power-

offset words and “dldh” is a power -offset word. Both
“clch” and “dldh” are two-by te binar y words se nt
LOW byte first and HI GH byte seco nd . Th e pow er­offset word is in hundr eths of a dB. Negativ e pow er
offsets use twos-complement representation.

To change a powe r -o ffset wor d in the table, use the
PTC dldh command, where “dldh” is the new power-
offset word for the cur r ent powe r lev el settin g.

Progr am min g Note:

Care must be taken to send the exact number of
power- offset wo rds spec ified in the wordco unt, “clch”.
If to few words are sent, the GPIB in terf ace may not
respond properly.

Figures 3-14 and 3-14a show an example of pow er-offset mode program­ming.

Table 3-16. Power-Offset-Table Commands

MNEMONIC

CODE

PT0 Disable the Power Offset Table
PT1 Enable the Power Offset Table

PTC Change a Power Offset Tab le entry (PTC dldh), wh ere dldh is

the new offset word for the current table entry.

PTL Load a Power Offset Table (PTL clch dldh . ..), whe re clch is th e

data word count and dldh is the data word.

FUNCTION

3-34 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE POWER-OFFSET­67XX GPIB COMMANDS TABLE COMMANDS

The follow ing is an example of power- off se t mode prog ramm ing. This progr am is written for use w ith an IBM-PC t ype
computer /c ont ro ller cont aining an IOtec h GPIB int er fa ce.

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

/* IOtech Driver488/LIB Subroutine Interface definitions... */
#include "\ieee488\iotlib .h"
#include "\ieee488\iot_ma in.h"

/* Define the device handles */
DevHandleT Synth,ieee;

void main()
{
char CmdString[10], DataString[40], String[40];
unsigned char XString[160];

int next_step,i,j;

/*************************************************************************/
/* Initialize the IOtech interface board and */
/* obtain the interface’s handle. */

#defin e ADDRESS 5

if((ieee=InitIeee488(btMP488CT, 21, -1, 0x02el, 7, 5, 1, 10000,0))==-1)
{
printf("Cannot initialize IEEE 488 system.\n")
exit(1);
}

if(( Synth=CreateDevice( ADDRESS, -1 ) )==-1)
{
printf("Cannot create Synth device.\n");
exit(1);

/* Set the device timeout so you don’t wait forever if there’s a problem */
TimeOut(Synth, 2000);

/* Handle the errors in the program */
Error(Synth,OFF);

/*************************************************************************/

/* Address the Synthesizer to listen */

NOTE: This program is continue d in Figur e 3-14a .

Figure 3-14. Power-Offset Mode Progr am m ing Exa m ple (1 of 2)

681XXA PM PRELIMINARY 3-35

PROGRAMMING WITH COMPATIBLE POWER-OFFSET­67XX GPIB COMMANDS TABLE COMMANDS

strcpy(XString,"_?U%");
SendCmd(Synth,XString,strlen(XString));

Output(Synth,"RST");
Output(Synth,"GTF");
Output(Synth,"ZL000");
Output(Synth,"1 GH 2 GH 3 GH 4 GH 5 GH 6 GH 7 GH 8 GH 9 GH 10 GH");
Output(Synth,"ZEL");

/* Make a data array with the PTL command, the word count */
/* and the binary data in low-byte, high-byte order. */
DataString[0]=’P’;
DataString[1]=’T’;
DataString[2]=’L’;
DataString[3]=10; /* Low byte -- ten words */
DataString[4]=0; /* High byte -- */
DataString[5]=0; /* 0 */
DataString[6]=0;
DataString[7]=20; /* 276 */
DataString[8]=1;
DataString[9]=30; /* 542 */
DataString[10]=2;
DataString[11]=40; /* 808 */
DataString[12]=3;
DataString[13]=50; /* 1074 */
DataString[14]=4;
DataString[15]=60; /* 1340 */
DataString[16]=5;
DataString[17]=70; /* 1606 */
DataString[18]=6;
DataString[19]=80; /* 1872 */
DataString[20]=7;
DataString[21]=90; /* 2138 */
DataString[22]=8;
DataString[23]=100; /* 2404 */
DataString[24]=9;

/* Send the data with an EOI on the last byte */
SendEoi(Synth,DataString,25);

Output(Synth,"ZS000");

for(next_step=0;next_step<10;next_step++)
{
Output(Synth,"Y");
printf("Press Enter for Next Frequency");
getchar();
}

} /* End of main() */

Figure 3-14a. Power-Of fset M ode Progr am m ing Exa m ple (2 of 2)

3-36 PRELIMINARY 681XXA PM

MNEMONIC

CODE

FUNCTION

TST Executes a sweep genera to r self te st. Exte n ded St at us Byt e 1

bit 0 is set if self tes t f ails; bit 2 is set when self test is com plete.

Table 3-17. Self Test Commands

PROGRAMMING WITH COMPATIBLE SELF TEST
67XX GPIB COMMANDS COMMANDS

3-17

SELF TEST
COMMANDS

Table 3-17 lists the self test command mnemonic codes. These co m­mands provide for executin g a sweep generator self test.

When a TST command is received, the sweep gene rator perfor ms a self
test, then places a “P” (for pass) or a “F” (for fail) on the bus. It also
generates six self test results bytes. Figure 3-16 (next page) shows the
six self test results bytes and identifies the repo rtin g func tio n of each
bit.

When self test is completed, bit 7 of Self Test Results Byte 6 and bit 2
of Extended Status Byte 1 are both set. If a failure(s) occur s durin g self
test, the Self Test Results Byte bit(s) reporting the failure (s) and bit 0
of Extended Status Byte 1 are set.

The OSR command returns the six self test results bytes to the co ntr ol­ler. Figure 3-15 provides an example of self test command program­ming.

Progr am min g Note: The “P or “F” characte r placed on the bus by the
sweep generator self test must be cleared from the outpu t buffe r (read
by the controller) before anoth er outpu t comman d, such as OSR, is
sent. If it is not cleared, the first ch arac ter of the next ou tp ut will be
missing. Line 30 (Fig u re 3-15) show s clearing of the “P” or “F” charac­ter.

Figure 3-15. Self Te st Com ma nd Pr ogra mmi ng Exa mple

681XXA PM PRELIMINARY 3-37

10 OUTPUT 705; "CSB"
20 OUTPUT 705; "TST"
30 ENTER 705; D$
40 DISP D$
50 OUTPUT 705; "OSR"
60 ENTER 705 USING "#,B"; A, B, C, D, E, F
70 DISP A; B; C; D; E; F
80 END

PROGRAMMING WITH COMPATIBLE SELF TEST
67XX GPIB COMMANDS COMMANDS

Self Test R esults Byte 1

Sweep Time

Circuitry Failed

Bit 7

(128)

A18 Power

Supply is Not

Locked

Bit 6

(64)

Self Test R esults Byte 2

Not Locked

Indicator

Check Failed

Bit 7

(128)

Down Converter

is

Not Locked

Bit 6

(64)

Self Test R esults Byte 3

Detector Log

Amp Circuitry

Failed

Bit 7

(128)

Level Reference

Circuitry

Failed

Bit 6

(64)

Power Supply
Voltage(s) are

Out of Reg

Bit 5

(32)

YIG Loop

Circuitry is

Not Locked

Bit 5

(32)

Not Leveled

Detector

Circuitry Failed

Bit 5

(32)

A12 –10 Volt

Reference

Check Failed

Bit 4

(16)

Coarse Loop

Circuitry is

Not Locked

Bit 4

(16)

Delta-F Ramp

Circuitry

Failed

Bit 4

(16)

A12 +10 Volt

Reference

Check Failed

Bit 3

(8)

Fine Loop

Circuitry is

Not Locked

Bit 3

(8)

Center

Frequency

Circuitry Failed

Bit 3

(8)

DVM –10 Volt

Reference

Check Failed

Bit 2

(4)

High Stability

Crystal is

Not Locked

Bit 2

(4)

Marker Switch

Point

Circuitry Failed

Bit 2

(4)

DVM +10 Volt

Reference

Check Failed

Bit 1

(2)

Ext 10 MHz

is

Not Locked

Bit 1

(2)

Linearizer

Circuitry

Failed

Bit 1

(2)

DVM Ground
Offset Check

Failed

Bit 0

(1)

Oven

is

Not Ready

Bit 0

(1)

FM Loop

Gain

Circuitry Failed

Bit 0

(1)

Self Test R esults Byte 4

3.3 - 5.5 GHz

Switch Filter

Section or

Level Detector

Circuitry Failed

Bit 7

(128)

2-3.3 GHz

Switch Filter

Section or

Level Detector

Circuitry Failed

Bit 6

(64)

Self Test R esults Byte 5

33 - 40 GHz

Section of

Frequency

Extension Unit

Failed

Bit 7

(128)

Frequency

Extension Unit

or Driver

Circuitry Failed

Bit 6

(64)

Self Test R esults Byte 6

Self Test

is

Complete

Bit 7

(128)

Not Used Not Used RF Was Off

Bit 6

(64)

Switch Filter

or

Level Detector

Circuitry Failed

Bit 5

(32)

20 - 26.5 GHz

Modulator or

Driver Circuitry

On A14 Failed

Bit 5

(32)

Bit 5

(32)

0.01 - 2 GHz
Range

Unleveled

Bit 4

(16)

26.5 - 40 GHz
Modulator or

Driver Circuitry

on A14 Failed

Bit 4

(16)

When Self Test

Started

Bit 4

(16)

A10 Q5 or

Associated

Circuitry Failed

Bit 3

(8)

Modulator or

Driver Circuitry

on A9 Failed

Bit 3

(8)

Slope DAC or

Associated

Circuitry Failed

Bit 3

(8)

2 - 8.4 GHz

Range

Unleveled and

Not Locked

Bit 2

(4)

13.25 - 20 GHz
Switch Filter

Section or

Level Detector

Circuitry Failed

Bit 2

(4)

Sample and

Hold Circuitry

Failed

Bit 2

(4)

8.4 - 20 GHz
Range

Unleveled and

Not Locked

Bit 1

(2)

8.4 - 13.25 GHz
Switch Filter

Section or

Level Detector

Circuitry Failed

Bit 1

(2)

20 - 26.5 GHz

Section of

Frequency

Extension Unit

Failed

Bit 1

(2)

2 - 20 GHz

Range

Unleveled and

Not Locked

Bit 0

(1)

5.5 - 8.4 GHz
Switch Filter

Section or

Level Detector

Circuitry Failed

Bit 0

(1)

26.5 - 33 GHz
Section of

Frequency

Extension Unit

Failed

Bit 0

(1)

Figure 3-16. Self Te st Res ul ts Bytes

3-38 PRELIMINARY 681XXA PM

MNEMONIC

CODE

FUNCTION

CS0 Turns off the C W ram p.
CS1 Tur ns on the C W ramp. This produces a repetitive 0V to 10 V

ramp output to the rea r panel HORI Z OU T con nect or and pin 1
of the AUX I/O connector.

DS0 Tur ns on the se cur e mode. This blank s the fron t p anel disp lay

of all frequency, power level, and modulat io n par am eters .

DS1 Turns of f the secur e mode and restores the fro nt panel display

of all frequency, power level, and modulat io n par am eters .

RL Returns the 681XXA to local (front panel) control.

RST Resets the 681XXA to its default settings.

NOTE

Sending this command clea rs the cu rrent inst rumen t
setup. If this set up is need ed for fut ur e testin g, save it
as a stored setup (p ara gra ph 3- 11) befor e send in g
RST.

SNR Permits entry of the instrumen t serial num ber (SNRnn nnnn X).

The serial numb er, represente d by nnn nnn, must be six
characters in length.

Table 3-18. Miscellaneo us Com m an ds

PROGRAMMING WITH COMPATIBLE MISCELLANEOUS
67XX GPIB COMMANDS COMMANDS

3-18

MISCELLANEOUS
COMMANDS

Table 3-18 is a list of miscellaneous command mnemonic codes th at do
not fit into any of the other classification s. Th ese comman ds prov ide
the following oper atio ns:

CW Ramp
Secure Mode
Returning the 681XXA to local control
Instrument Reset
Serial Number Entry

681XXA PM PRELIMINARY 3-39

PROGRAMMING WITH COMPATIBLE PROGRAM
67XX GPIB COMMANDS ERRORS

3-19

PROGRAM ERRORS

Two types of errors can occur in bus programmin g —in v alid-p arame ter
and syntax. These two er ror typ es are described in the following para­graphs.

Invalid­Parame te r

Syntax Syntax errors are those that occur in the formula-

Invalid-par ameter error s are those that cause the
sweep generator to beep. These errors include:

Programming a frequency swee p wher e the
sweep start frequenc y is greater than the stop
frequency.
Attempting to enter a frequency, time, or power
level parameter that exceeds the limits of the
sweep generator.
Failing to proper ly end a parameter entry with
a suitable terminator such as MH, DB, MS, etc.

tion of a program statement, such as writing
"EXTTFS" instead of "EXTTRS".

To prevent misinterpretation of command state­ments, the sweep gen er ator igno re s all portions of
the command statement following the syntax err or.

All commands are ignored until the sweep g ener a tor
receives the Unlisten co mmand (ASCII 63; “?” char­acter) over the bus or until the swe ep gene rator i s ad­dressed to talk.

3-40 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE RESET PROGRAMMING
67XX GPIB COMMANDS AND DEFAULT CONDITIONS

3-20

RESET PROGRAM­MING AND DEFAULT
CONDITION S

Table 3-19 describes the five methods that can be used to reset the
sweep generator. They prov ide a means for quic kly re tur ning the
sweep generator to its default (pr epr ogr ammed) ope ration al state.

The default settings for the numeric frequency, sweep time, and power
level parameters are the same as those listed in T able 3-1 on page 3-14
of the Series 681X XA Synthesize d Sweep Generator Operation Manual
(P/N 10370-10250).

Figure 3-17 (next pag e) prov ides an example of a recommen de d se­quence for programmin g a reset command. Using this comman d se­quence ensur es that all parameter s and comman ds a ssume their pr e­programmed state each time reset is desired.

Table 3- 19. Resetting the 681XXA GPIB Interface Circuits

Methods of Resetting

GPIB Inte rface Ci rc ui ts

1. Pressing the front panel
menu RETURN TO LO­CAL soft-key.

2. Pressing the front panel
System me nu RESET
soft-ke y.

Functio ns

Affected

Bus Messages Local

Service Request Modes ES0, FB0, PE0, SB0,

SE0, SQ0, UL 0, SB0
GTS
Local and Local Lockout

Default

Conditions

3. Sending the RST com­mand over the bus.

4. Executing the int er face
message Device Clear.

5. Turning p ower on and
off.

Same as 2 above Same as 2 above except

that the local bus
message is not res et .

Same as 2 above. Same as 2 ab ove ex cept

that the local bus
message is not res et .

Same as 2 above. Places the GPIB into the

power-on state.
Instrument state does not
change.

681XXA PM PRELIMINARY 3-41

PROGRAMMING WITH COMPATIBLE PROGRAMMING
67XX GPIB COMMANDS EXAMPLES

Sample Codin g In Basic

10 CLEAR 705
20 OUTPUT 705; "FUL IL1 L1 10DM"

Explanation of Code

Line 10 sends the Device Clear bus mess age. Th is message cle ars the sweep gen­erator GPIB interface.

Line 20 sends new front panel sett ings: Full Sweep, Inte rna l Leveling, and Outpu t
Power Level of 10 dBm.

Figure 3-17. Reset Progr am m ing Exampl e

3-21

PROGRAMMING
EXAMPLES

Figures 3-18 thru 3-20, on the following pages, provide three examples
of GPIB programmin g of the sweep gen er ator usin g comp atible
WILTRON Model 67XX Synthesizer GPIB commands.

3-42 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE PROGRAMMING
67XX GPIB COMMANDS EXAMPLES

The following subroutine uses the output identify (OI) comm and to identify the
sweep generator’s model numbe r, serial number, minimum and maxim um freque n­cies, minimum and maximum power level, and so ftware revision level. This subrou­tine is used in the examp le prog ram s in Figures 3- 19 an d 3-2 0 to read the limits of
the sweep generator.

10 ! "GET OI"
20 ! Gets the output id string
30 ! from a 68XXXX Sweep Generator
100 OUTPUT 705; "OI"
110 DIM A$[36]
120 ENTER 705; A$
130 M$=A$[1,2] ! Model
140 M1$=A$[3,4] ! Model Number
150 F1$=A$[5,9] ! Freq Low
160 F2$=A$[10,14] ! Freq High
170 L2$=A$[15,20] ! Min Power
180 L1$=A$[21,24] ! Max Power
190 S$=A$[25,28] ! Software Ver
200 S1$=A$[29,34] ! Serial Number
210 P$=A$[35,35] ! Model Prefix
220 S2$=A$[36] ! Series
230 PRINT "Model Number :";M$;S2$;M1$;P$
240 PRINT "Serial Number :";S1$
250 PRINT "Low Freq :";F1$
260 PRINT "High Freq :";F2$
270 PRINT "Max Power :";L1$
280 PRINT "Min Power :";L2$
290 PRINT "Software Ver :";S$
300 END

Program Expla nat io n

Line 100:
Line 110:
Line 120:
Line 130:
Line 140:
Line 150:
Line 160:
Line 170:
Line 180:
Line 190:
Line 200:
Line 210:
Line 220:
Lines 230-290:

Figure 3-18. Using the Output Identify (OI) Comm an d

Sends the "OI" comma n d.
Dimensions the variable.
Gets the "OI" string.
Sets M$ to the model (68).
Sets M1$ to the model number.
Sets F1$ to the sweep generat or low-end freque ncy.
Sets F2$ to the sweep generat or high-e nd f req uenc y.
Sets L2$ to the minimum power point.
Sets L1$ to the maximu m power p o int.
Sets S$ to the software version nu mb er.
Sets S1$ to the serial number.
Sets P$ to the model prefix number (1 or 2).
Sets S2$ to the model series (A or B).

Prints the data obtained.

681XXA PM PRELIMINARY 3-43

PROGRAMMING WITH COMPATIBLE PROGRAMMING
67XX GPIB COMMANDS EXAMPLES

The following program (1) rec eives en tries from the key boar d to set intial frequency
and step-siz e param et ers , an d (2) activates the soft keys on the con troller so tha t
they can step the f req uenc y up or down.

20 ! PARAMETER ENTRY, SYZ, UP, AND DN COMMANDS
30 Address=705
40 CALL Iddev(Address,Model,Fmin,Fmax,Pmin,Pmax)
50 OFF KEY

Program Explanation

Line 30:

sweep generat or.

Line 40:

subrout ine des cribe d in Line 1010 .

Line 50:
Lines 60-110:

quency entry and che cks it s validity.

Lines 120-170:

entry and checks its val idity.

Line 180:

to the startin g frequ ency and step
size.

Lines 190-240:

labels.

Line 250:

pressed.

Line 300:

key was pressed; send s the UP co m­mand.

Line 310:
Line 320:

DOWN key wa s pressed ; send t he
DN command.

Line 330:
Line 340:
Lines 1010-1120 :

generator address, model, frequency
range, and power range.

Sets the address of the
Calls the device identification
Turns of f t he key definitions.

Accept the starting fre-

Accept the step size

Sets the sweep generator

Set up keys and key
Waits for a key to be
Reports that the STEP UP

Waits for the next key.

Reports that the STEP

Waits for the next key.
Ends the main progr am.

Identify the sweep

60 DISP "ENTER FREQUENCY IN GHz";
70 INPUT Freq
80 IF Freq>Fmax OR Freq<Fmin THEN
90 DISP "FREQUENCY OUT OF RANGE - ";
100 GOTO 60
110 END IF
120 DISP "ENTER STEP SIZE IN GHz";
130 INPUT Stepsize
140 IF Stepsize>Fmax-Fmin OR Stepsize<.000001 THEN
150 DISP "ILLEGAL STEP SIZE - ";
160 GOTO 120
170 END IF
180 OUTPUT Address;"CF1";Freq;"GH SYZ";Stepsize;"GH"
190 ON KEY 0 LABEL "STEP" GOTO 300
200 ON KEY 5 LABEL " UP " GOTO 300
210 ON KEY 1 LABEL "STEP" GOTO 320
220 ON KEY 6 LABEL "DOWN" GOTO 320
230 ON KEY 2 LABEL "NEW " GOTO 50
240 ON KEY 7 LABEL "FREQ" GOTO 50
250 GOTO 250
300 OUTPUT Address;"UP"
310 GOTO 250
320 OUTPUT Address;"DN"
330 GOTO 250
340 END
1010 SUB Iddev(Address,Model,Fmin,Fmax,Pmin,Pmax)
1020 DIM Ident$[36]
1030 OUTPUT Address;"OI"
1040 ENTER Address;Ident$
1050 Model=VAL(Ident$[1,2])
1060 Model Number=VAL(Ident$[3,4])
1070 Fmin=VAL(Ident$[5,9])
1080 Fmax=VAL(Ident$[10,14])
1090 Pmin=VAL(Ident$[15,20])
1100 Pmax=VAL(Ident$[21,24])
1110 Model Prefix=Ident$[35,35]
1120 Series=VAL(Ident$[36])
1130 SUBEND

Figure 3-19. Controlling CW Frequency /Par am e ter Entrie s

3-44 PRELIMINARY 681XXA PM

PROGRAMMING WITH COMPATIBLE PROGRAMMING
67XX GPIB COMMANDS EXAMPLES

The following program accept s user input s for (1) power swe ep star ting and end ing
levels, (2) number of steps in t he s weep, an d (3) swe ep dw e ll time s. After acc ept ing
such imputs, the progr am th en comm and s the sweep generat or to obtain a display
of the power sweep .

NOTE: The swe ep gen era tor sho uld be con nect ed to a scalar net wor k ana lyzer.

30 Address=705
40 CALL Iddev(Address,Model,Fmin,Fmax,Pmin,Pmax)
60 DISP "ENTER POWER SWEEP STARTING LEVEL (dBm)";
70 INPUT Powerstart
80 IF Powerstart>Pmax OR Powerstart<Pmin THEN

Program Explanation

Line 30:

sweep generat or.

Line 40:

subrout ine des cribe d in line 1010.

Lines 60-110:

power level ent ry and checks its val id­ity.

Lines 120-170:

power level ent ry and checks its val id­ity.

Lines 180-230:

sweep number-of -s teps ent r y and
checks it validity.

Lines 240-290:

sweep dwell time entry and check s
its validity.

Lines 300-310:

ator to perform the abov e defined
power sweep.

Line 340:
Lines 1010-1120 :

generator address, model, frequency
range, and power range.

Set the address of the
Call the device identification

Accept the starting

Accept the en ding

Accept the power

Accept the power

Sets the sweep gener-

Ends the main program.

Identify the sweep

90 DISP "POWER OUT OF RANGE - ";
100 GOTO 60
110 ENDIF
120 DISP "ENTER POWER SWEEP ENDING LEVEL (dBm)";
130 INPUT Powerstop
140 IF Powerstop>Pmax OR Powerstop<Pmin THEN
150 DISP "POWER OUT OF RANGE - ";
160 GOTO 120
170 END IF
180 DISP "ENTER NUMBER OF STEPS";
190 INPUT Noofsteps
200 IF Noofsteps<1 OR Noofsteps>1000 THEN
210 DISP "NUMBER OF STEPS OUT OF RANGE - ";
220 GOTO 180
230 END IF
240 DISP "ENTER DWELL TIME AT EACH STEP (mS)";
250 INPUT Dwell
260 IF Dwell<100 OR Dwell>10000 THEN
270 DISP "DWELL TIME OUT OF RANGE - ";
280 GOTO 240
290 END IF
300 OUTPUT Address;"L1";Powerstart:"DM L2";Powerstop;
"DM PNS";Noofsteps;"SPS"
310 OUTPUT Address;"PDT";Dwell;"MS LSP"
340 END
1010 SUB Iddev(Address,Model,Fmin,Fmax,Pmin,Pmax)
1020 DIM Ident$[36]
1030 OUTPUT Address;"OI"
1040 ENTER Address;Ident$
1050 Model=VAL(Ident$[1,2])
1060 Model Number=VAL(Ident$[3,4])
1070 Fmin=VAL(Ident$[5,9])
1080 Fmax=VAL(Ident$[10,14])
1090 Pmin=VAL(Ident$[15,20])
1100 Pmax=VAL(Ident$[21,24])
1110 Model Prefix=Ident$[35,35]
1120 Series=VAL(Ident$[36])
1130 SUBEND

Figure 3-20. Controlling Pow er Level and Powe r Sw e ep

681XXA PM PRELIMINARY 3-45/3-46

Appendix A
SCPI
Conformance Information

– SCPI Conforma nce Info rmati o n wil l be suppl ied at a l ater date. –

681XXA PM PRELIMINARY A-1

Appendix B
Index of Compatible 67XX
GPIB C ommands

B-1

INTRODUCTION

This appendix provides an alphabetical index of the WILTRON Model
67XX GPIB Product Specific Commands accepted and implemented
by the 681XXA. The index lists the command mnemonic code, a brief
description of the command function, and the page number in Chap­ter 3 where a complete description of the command can be found.

Compatible 67XX GPIB Commands (1 of 8)

Command

Code

ACW Activates currently scanned frequency as CW 3-10

AD1
AD5
AD6

AF1 Selects F1-F2 alternate sweep 3-12

AF3 Selects F3-F4 alternate sweep 3-12
AFU Selects Full Range alternate sweep 3-12
AM0 Turns off the external AM function 3-18
AM1 Turns on the external AM function in Linear mode 3 -18
AM2 Turn on the external AM function in Log mode 3-18
AUT Selects Auto sweep trigger 3-12
BPN Selects –5V for retrace and bandswitch blanking outputs 3-31
BPP Selects +5V for retrace and bandswitch blanking outputs 3-31
CF0 Set CW mode at F0, Opens F0 parameter 3-10
CF1 Set CW mode at F1, Opens F1 parameter 3-10
CF2 Set CW mode at F2, Opens F2 parameter 3-10
CF3 Set CW mode at F3, Opens F3 parameter 3-10
CF4 Set CW mode at F4, Opens F4 parameter 3-10
CF5 Set CW mode at F5, Opens F5 parameter 3-10
CF6 Set CW mode at F6, Opens F6 parameter 3-10
CF7 Set CW mode at F7, Opens F7 parameter 3-10
CF8 Set CW mode at F8, Opens F8 parameter 3-10
CF9 Set CW mode at F9, Opens F9 parameter 3-10
CLO Closes the open parameter 3 -6

Selects F1-∆F alternate sweep
Selects F5-∆F alternate sweep
Selects F6-∆F alternate sweep

Function

Page

Number

3-12
3-12
3-12

681XXA PM PRELIMINARY B-1

INDEX OF COMPATIBLE
67XX GPIB COMMANDS

Compatible 67XX GPIB Commands (2 of 8)

Command

Code

CLR Clears data entry 3-8
CM0 Set CW mode at M0, Opens M0 parameter 3-10
CM1 Set CW mode at M1, Opens M1 parameter 3-10
CM2 Set CW mode at M2, Opens M2 parameter 3-10
CM3 Set CW mode at M3, Opens M3 parameter 3-10
CM4 Set CW mode at M4, Opens M4 parameter 3-10
CM5 Set CW mode at M5, Opens M5 parameter 3-10
CM6 Set CW mode at M6, Opens M6 parameter 3-10
CM7 Set CW mode at M7, Opens M7 parameter 3-10
CM8 Set CW mode at M8, Opens M8 parameter 3-10
CM9 Set CW mode at M9, Opens M9 parameter 3-10

CSO Turns off the CW ramp 3-39

CS1 Turns on the CW ramp 3-39

CSB Clears all GPIB status bytes 3-29

DB dB data terminator 3-8
DF0
DF1
DF5
DF6
DFF

DFM

DL1 Selects external detector leveling of the output power 3-20
DLF

DM dBm data terminator 3-8

DN Decrements the open parameter by the step size 3-8
DS0

DS1

DU0 Deselects Dual Step sweep mode 3-13
DU1 Selects Dual Step sweep mode on 3-13
EG1 Enter value for external level gain DAC directly 3-21

EGO Output value of external level gain DAC 3-21

EL0 Inhibits updating of the ESB2 bit 4 (RF Unlocked) 3-29

EL1 Enables updating of the ESB2 bit 4 (RF Unlocked) 3-29
EP0 External pulse input; TTL high is RF off 3-31
EP1 External pulse input; TTL high is RF on 3-31
ES0 Inhibits End-of-Sweep SRQ generation 3-28

Selects the F0-∆F sweep mode
Selects the F1-∆F sweep mode
Selects the F5-∆F sweep mode
Selects the F6-∆F sweep mode
Opens the ∆F parameter (Same as DLF)
Opens the ∆F parameter (Same as DLF)

Opens the ∆F parameter

Tur ns on the sec ure mode ( B lanks th e front pa nel display
of Frequency, Power Level, and Modulation parameters)

Turns off the secure mode and restores front panel
display of all parameters

Function

Page

Number

3-11
3-11
3-11
3-11

3-7
3-7

3-7

3-39

3-39

B-2 PRELIMINARY 681XXA PM

Command

Code

Function

Page

Number

ES1 Enables End-of-Sweep SRQ generation 3-28
EXT Selects single sweep trigger 3-12

F0 Opens the F0 parameter 3-7
F1 Opens the F1 parameter 3-7
F2 Opens the F2 parameter 3-7
F3 Opens the F3 parameter 3-7
F4 Opens the F4 parameter 3-7
F5 Opens the F5 parameter 3-7
F6 Opens the F6 parameter 3-7
F7 Opens the F7 parameter 3-7
F8 Opens the F8 parameter 3-7

F9 Opens the F9 parameter 3-7
FB0 Inhibits Extended Status Byte 1 SRQ generation 3-28
FB1 Enables Extended Status Byte 1 SRQ generation 3-28
FM0 Turns off the external FM function 3-18
FM1 Turns on the external FM funtion in Narrow mode 3-18

FMS Opens the FM sensitivity parameter 3-18
FMU Turns on the external FM function (Same as FM1) 3-18

FMW Turns on the external FM function in Wide mode 3-18

FUL Selects the Full Range sweep mode 3-11

GH GHz data terminator 3-8

GTC

Scans to the next higher preset CW frequency on a GET
(Executes a “SQF” command)

3-32

GTD

Steps the open parameter down by the step size on a
GET (Executes a “DN” command)

3-32

GTF

Executes a Fast-frequ ency-swit ching step on a GE T (Se e
“ZL, ZEL” commands)

3-32

GTL

Steps to the next point in a dual step sweep mode on a
GET (Executes a “TSS” command)

3-32
GTO Disables the GET functions 3-32
GTS

Triggers a single sweep on a GET (Executes a “TRS”
command

3-32

GTT

Executes a complete sweep gen era tor self test on a GET
(Executes a “TST” command)

3-32

GTU

Steps the open parameter up by the setp size on a GET
(Executes an “UP” command)

3-32

GV GHz per volt (GHz/V) data terminator 3-8

HZ Hz data terminator 3-8
II0 Enables updating of the ESB2 bit 7 (Paramet er Changed) 3-29
II1 Inhibits updating of the ESB2 bit 7 (Parameter Changed) 3-29

Compatible 67XX GPIB Commands (3 of 8)

INDEX OF COMPATIBLE
67XX GPIB COMMANDS

681XXA PM PRELIMINARY B-3

INDEX OF COMPATIBLE
67XX GPIB COMMANDS

Compatible 67XX GPIB Commands (4 of 8)

Command

Code

IL1 Selects internal leveling of the output power 3-20

IM1 Turns on the Intensity marker mode 3-16

KH kHz data terminator 3-8
KV kHz per volt (kHz/V) data terminator 3-8

L1 Selects the L1 power level value as the RF output power 3-20

L2 Selects the L2 power level value as the RF output power 3-20
LE0 Inhibits Lock Error SRQ generation 3-28
LE1 Enables Lock Error SRQ generation 3-28

LOS Opens the level offset parameter 3-7
LO0 Turns off the Level Offset function 3-20
LO1 Turns on the Level Offset function 3-20
LSP Selects the Power Sweep mode 3-21

LV0 Turns off leveling of the output power 3-21

M0 Opens the M0 parameter 3-7
M1 Opens the M1 parameter 3-7
M2 Opens the M2 parameter 3-7
M3 Opens the M3 parameter 3-7
M4 Opens the M4 parameter 3-7
M5 Opens the M5 parameter 3-7
M6 Opens the M6 parameter 3-7
M7 Opens the M7 parameter 3-7
M8 Opens the M8 parameter 3-7
M9 Opens the M9 parameter 3-7

MAN Selects manual (step) sweep 3-14

MB0 Sets the enable mask byte for the Primary Status Byte 3-28
MB1 Sets the enable mask byte for Extended Status Byte 1 3-28
MB2 Sets the enable mask byte for Extended Status Byte 2 3-28
ME0 Disables the marker at the active frequency 3-16
ME1 Enables a marker at the active frequency 3-16

MH MHz data terminator 3-8

MK0 Turns off ma rke rs 3-16

MS Milliseconds (ms) data terminator 3-8

MV MHz per volt (MHz/V) data terminator 3-8
ODF
OEM Outputs the Extended SRQ Mask bytes (3 binary bytes) 3-23
OES Outputs all three GPIB status bytes 3-23

OF0 Outputs the F0 frequency value in MHz 3-22

Output s the ∆F frequency value in MHz

Function

Page

Number

3-23

B-4 PRELIMINARY 681XXA PM

Compatible 67XX GPIB Commands (5 of 8)

INDEX OF COMPATIBLE
67XX GPIB COMMANDS

Command

Code

OF1 Outputs the F1 frequency value in MHz 3-22
OF2 Outputs the F2 frequency value in MHz 3-22
OF3 Outputs the F3 frequency value in MHz 3-22
OF4 Outputs the F4 frequency value in MHz 3-22
OF5 Outputs the F5 frequency value in MHz 3-22
OF6 Outputs the F6 frequency value in MHz 3-22
OF7 Outputs the F7 frequency value in MHz 3-22
OF8 Outputs the F8 frequency value in MHz 3-22
OF9 Outputs the F9 frequency value in MHz 3-22

OFH Outputs the high-end frequency value in MHz 3-22

OFL Outputs the low-end frequency value in MHz 3-22

OI Outputs the instrument identification string 3-22

OLO Outputs the Level Offset power level in dB 3-23

OL1 Outputs the L1 power level value in dBm 3-23

OL2 Outputs the L2 power level value in dBm 3-23
OM0 Outputs the M0 frequency value in MHz 3-22
OM1 Outputs the M1 frequency value in MHz 3-22
OM2 Outputs the M2 frequency value in MHz 3-22
OM3 Outputs the M3 frequency value in MHz 3-22
OM4 Outputs the M4 frequency value in MHz 3-23
OM5 Outputs the M5 frequency value in MHz 3-23
OM6 Outputs the M6 frequency value in MHz 3-23
OM7 Outputs the M7 frequency value in MHz 3-23
OM8 Outputs the M8 frequency value in MHz 3-23
OM9 Outputs the M9 frequency value in MHz 3-23
OPD Outputs the power sweep dwell time in ms 3-23
OPS Outputs the power sweep number of steps 3-23
OSB Outputs the Primary Status Byte (1 binary byte) 3-23
OSD Outputs the step sweep dwell time in ms 3-23
OSE Outputs the last GPIB syntax error 3-23

OSM Outputs the primary SRQ Mask byte (1 binary byte) 3-24

OSR Outputs the self-test results (6 binary bytes) 3-24
OSS Outputs the step sweep number of steps 3-23
OST Outputs the sweep time value in ms 3-23
OVN Outputs the ROM version number string 3-23

OWT Outputs the GPIB termination status; 0 = CR, 1 = CRLF 3-23

P0 Turns off the square wave/pulse modulation mode 3-19

Function

Page

Number

681XXA PM PRELIMINARY B-5

INDEX OF COMPATIBLE
67XX GPIB COMMANDS

Compatible 67XX GPIB Commands (6 of 8)

Command

Code

PCV Percent per volt (%/V) data terminator 3-8

PDT Opens the power sweep dwell time parameter 3-7
PE0 Inhibits Parameter Range Error SRQ generation 3-28
PE1 Enables Parameter Range Error SRQ generation 3-28

PL1 Selects external power meter leveling of the output power 3-21

PNS Opens the power sweep number of steps parameter 3-7

PP0 Selects normally-open contacts on the pen lift relay 3-31
PP1 Selects normally-closed contacts on the pen lift relay 3-31
PT0 Disables the Power Offset Table 3-34
PT1 Enables the Power Offset Table 3-34
PTC Changes a Power Offset Table entry 3-34
PTL Loads a Power Offset Table 3-34

RC0

RC1

RCF

RCM

RF0 Turns off the RF output 3-20
RF1 Turns on the RF output 3-20

RL Returns the instrument to local control 3-39

RSN(M

RSS Reset a sweep if in progress 3-13

RST Resets the instrument to its default settings 3-39
RT0 Selects RF to be off during retrace 3-31
RT1 Selects RF to be on during retrace 3-31
SAF Outputs the current instrument setup to the controller 3-24

SAM

SB0 Inhibits Extended Status Byte 2 SRQ generation 3-28
SB1 Enables Extended Status Byte 2 SRQ generation 3-28
SDT Opens the step sweep dwell time parameter 3-7
SE0 Inhibits Syntax Error SRQ generation 3-29
SE1 Enables Syntax Error SRQ generation 3-29

SEC Seconds data terminator 3-8

SF1 Selects the F1-F2 sweep mode 3-11

Selects RF off during frequency switching in CW or step
sweep modes

Selects RF on during frequency switching in CW or step
sweep modes

Readies the 681XXA to receive a new instrument setup
from the controller

Readies the 681XXA to receive a new instrument setup
and new stored setups from the controller

Recalls an instrument setup stored in internal setup

)

1 - 9

memory location M, where M = 1 to 9.

Outputs the current instrument setup and all stored
setups to the controller

Function

Page

Number

3-31

3-31

3-24

3-24

3-24

3-24

B-6 PRELIMINARY 681XXA PM

Compatible 67XX GPIB Commands (7 of 8)

INDEX OF COMPATIBLE
67XX GPIB COMMANDS

Command

Code

SF3 Selects the F3-F4 sweep mode 3-11

SM Recalls the next stored instrument setup in sequence 3-25
SNR Enter the instrument serial number (SNRnnnnnnX) 3-39
SNS Opens the step sweep number of steps parameter 3-7

SPS Steps data terminator 3-8
SP0 Deselects non-equally spaced step sweep 3-16
SP1 Selects non-equally spaced step sweep 3-16
SQ0 Disables the SRQ generation function 3-29

SQ1 Enables the SRQ generation function 3-29
SQD Scan down to next lower preset CW frequency 3-10
SQF Scan to next higher preset CW frequency 3-10
SQP Turns on internal square wave modulation at 1 kHz 3-18
SQU Scan up to next higher preset CW frequency 3-10

SSN(M

SSP Selects step sweep 3-14
SW0
SW1 Turns on internal square wave modulation at 400 Hz 3-18
SW2
SW3 Turns on internal square wave modulation at 7.8125 kHz 3-18

SW4 Turns on internal square wave modulation at 27.8 kHz 3-18

SWP Selects analog sweep 3-14
SWT Opens the analog sweep time parameter 3-7

SYZ Opens the increment/decrement size parameter 3-9
TRG Triggers a single sweep 3-13

TRS Triggers a single sweep 3-13

TSS Advances sweep to next step in dual step sweep mode 3-13

TST Starts an instrument self-test 3-37

UL0 Inhibits RF Unleveled SRQ generation 3-29
UL1 Enables RF Unleveled SRQ generation 3-29

UP Increment the open parameter by step size 3-8
US

VM1 Turns on the Video marker mode 3-16

XP Turns on the external square wave/pulse mode 3-19

ZL(X

000-999

Saves the current instrument setup in internal setup

)

1 - 9

memory location M, where M = 1 to 9

Turns off the square wave/pulse modulation mode
(Same as P0)

Turns on internal square wave modulation at 1 kHz
(Same as SQP)

Microseconds (µs) data terminator

Loads a CW frequency into the stack at location X (fast-

)

frequency-switching mode)

Function

Page

Number

3-24

3-19

3-18

3-8

3-33

681XXA PM PRELIMINARY B-7

INDEX OF COMPATIBLE
67XX GPIB COMMANDS

Compatible 67XX GPIB Commands (8 of 8)

Command

Code

ZEL Ends frequency loading (fast-frequency-switching mode) 3-33

Sets the stack pointer to point to location X (fast-

ZS(X

)

000-999

Y Equivalent to a Group Excute Trigger (GET) 3-32

frequency-switching mode)

Function

Page

Number

3-33

B-8 PRELIMINARY 681XXA PM