YOKOGAWA WT500 User manual

IM 760201-17E
3rd Edition
Power Analyzer
Communication Interface

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IM 760201-17E
3rd Edition: October 2017 (YMI)
All Rights Reserved, Copyright © 2008 Yokogawa Electric Corporation
All Rights Reserved, Copyright © 2015 Yokogawa Test & Measurement Corporation
Thank you for purchasing the WT500 Power Analyzer.
This Communication Interface User’s Manual describes the functions of the USB, GP-IB,
and Ethernet interfaces and communication commands. To ensure correct use, please
read this manual thoroughly before beginning operation. After reading the manual, keep it
in a convenient location for quick reference whenever a question arises during operation.
List of Manuals The following manuals, including this one, are provided as manuals for this instrument.
Please read all manuals.
Manual Title Manual No. Description
WT500 Power Analyzer
User’s Manual
IM 760201-01E
Explains all functions and procedures of the
WT500 excluding the communication functions.
WT500 Power Analyzer
Communication Interface
User’s Manual (CD)
IM 760201-17E This manual. Explains the functions for
controlling the WT500 using communication
commands.
WT500 Power Analyzer
Pulse Output Function (/P14
Optional) User’s Manual
IM 760201-51E Included with models with the /P14 option.
Explains the features of the Pulse Output
Function option and how to use them.
WT500 Power Analyzer
Pulse Output Function (/P17
Optional) User’s Manual
IM 760201-52E Included with models with the /P17 option.
Explains the features of the Pulse Output
Function option and how to use them.
WT500 Power Analyzer IM 760201-92 Document for China
The “E” in the manual number is the language code.
Contact information of Yokogawa offices worldwide is provided on the following sheet.
Document No. Description
PIM 113-01Z2 List of worldwide contacts
Note • The contents of this manual are subject to change without prior notice as a result of
continuing improvements to the instrument’s performance and functions. The figures
given in this manual may differ from those that actually appear on your screen.
• Every effort has been made in the preparation of this manual to ensure the accuracy
of its contents. However, should you have any questions or find any errors, please
contact your nearest YOKOGAWA dealer.
• Copying or reproducing all or any part of the contents of this manual without the
permission of YOKOGAWA is strictly prohibited.
• The TCP/IP software of this product and the document concerning the TCP/IP
software have been developed/created by YOKOGAWA based on the BSD Networking
Software, Release 1 that has been licensed from University of California.
USB Interface and Ethernet Interface
• The items below are needed on the PC to use the communication functions via the
USB interface.
• DL/WT series library (TMCTL)
• USB connection device driver between the PC and WT500
• The item below is needed on the PC to use the communication functions via the
Ethernet interface.
• DL/WT series library (TMCTL)
The library and driver above can be downloaded from the following Web page.
http://www.yokogawa.com/tm/

ii IM 760201-17E
Trademarks • Microsoft, Internet Explorer, MS-DOS, Windows, Windows NT, and Windows Vista
are either registered trademarks or trademarks of Microsoft Corporation in the United
States and/or other countries.
• Adobe and Acrobat are registered trademarks or trademarks of Adobe Systems
Incorporated.
• For purposes of this manual, the ® and TM symbols do not accompany their
respective registered trademark or rtrademark names.
• Other company and product names are registered trademarks or trademarks of their
respective holders.
Revisions • 1st Edition June 2008
• 2nd Edition December 2015
• 3rd Edition October 2017

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IM 760201-17E
Structure of the Manual
This User’s Manual consists of the following sections:
Chapter 1 USB Interface
Describes the functions and specifications of the USB interface.
Chapter 2 GP-IB Interface (Option)
Describes the functions and specifications of the GP-IB interface.
Chapter 3 Ethernet Interface (Option)
Describes the functions and specifications of the Ethernet interface.
Chapter 4 Before Programming
Describes the syntax used to transmit commands.
Chapter 5 Communication Commands
Describes all the commands one by one.
Chapter 6 Status Reports
Describes the status byte, various registers, queues, and other information.
Appendix
Describes reference material such as an ASCII character code table.
Index

iv IM 760201-17E
Symbols and Notation Used in This Manual
Unit and Note
Type Symbol Meaning
Unit k 1000 Example: 100 kHz
K 1024 Example: 640 KB (file data size)
Note Note Calls attention to information that is important for proper operation of the
instrument.
Subheadings On pages that describe operating procedures, the following symbols, displayed
characters, and terminology are used to distinguish the procedures from their
explanations:
Procedure Follow the numbered steps. All procedures are written with
inexperienced users in mind; experienced users may not need to
carry out all the steps.
Explanation This subsection describes the setup parameters and the limitations
on the procedures.
Displayed Characters and Terminology Used in the Procedural
Explanations
Panel Keys and Soft keys
Bold characters used in the procedural explanations indicate characters that are marked on the
panel keys or the characters of the soft keys or menus displayed on the screen.
SHIFT + Panel Key
SHIFT + key means you will press the SHIFT key to turn ON the SHIFT key followed by the
operation key. The setup menu marked in purple below the panel key that you pressed appears
on the screen.
Symbols Used in the Syntax
Symbols which are used in the syntax descriptions in Chapter 6 are shown below. These
symbols are referred to as BNF (Backus-Naur Form) symbols. For details on the data,
see pages 4-5 and 4-6.
Symbol Meaning Example Example of Input
< > Defined value. ELEMent<x> <x> = 1 to 4 ->ELEMENT2
{ } Select from values SCALING:{VT|CT|SFACtor}? ->SCALING:VT?
given in { }.
|Exclusive OR
[ ] Can be omitted. NUMeric[:NORMal]:VALue? ->NUMERIC:VALUE?

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Index
Contents
List of Manuals...................................................................................................................................i
Structure of the Manual.................................................................................................................... iii
Symbols and Notation Used in This Manual....................................................................................iv
Chapter 1 USB Interface
1.1 Names of Parts................................................................................................................. 1-1
1.2 USBInterfaceFunctionsandSpecications .................................................................... 1-2
1.3 Connection via the USB Interface .................................................................................... 1-3
Chapter 2 GP-IB Interface (Option)
2.1 Names and Functions of Parts ......................................................................................... 2-1
2.2 GP-IB Interface Functions ................................................................................................ 2-2
2.3 GP-IBInterfaceSpecications ......................................................................................... 2-3
2.4 Connecting the GP-IB Cable ............................................................................................ 2-4
2.5 Setting the GP-IB Control................................................................................................. 2-5
2.6 Responses to Interface Messages ................................................................................... 2-6
Chapter 3 Ethernet Interface (Option)
3.1 Names and Functions of Parts ......................................................................................... 3-1
3.2 EthernetInterfaceFunctionsandSpecications .............................................................. 3-2
Chapter 4 Before Programming
4.1 Messages ......................................................................................................................... 4-1
4.2 Commands ....................................................................................................................... 4-3
4.3 Responses ....................................................................................................................... 4-5
4.4 Data.................................................................................................................................. 4-6
4.5 Synchronization with the Controller.................................................................................. 4-8
Chapter 5 Communication Commands
5.1 A List of Commands ......................................................................................................... 5-1
5.2 COMMunicate Group ....................................................................................................... 5-9
5.3 CURSor Group ................................................................................................................5-11
5.4 DISPlay Group ............................................................................................................... 5-13
5.5 FILE Group..................................................................................................................... 5-24
5.6 HARMonics Group ......................................................................................................... 5-27
5.7 HOLD Group .................................................................................................................. 5-28
5.8 IMAGe Group ................................................................................................................. 5-29
5.9 INPut Group ................................................................................................................... 5-31
5.10 INTEGrate Group ........................................................................................................... 5-37
5.11 MEASure Group ............................................................................................................. 5-39
5.12 NUMeric Group .............................................................................................................. 5-43
5.13 RATE Group ................................................................................................................... 5-52
5.14 STATus Group ................................................................................................................ 5-53
5.15 STORe Group................................................................................................................. 5-55
5.16 SYSTem Group .............................................................................................................. 5-58
5.17 WAVeform Group............................................................................................................ 5-60
5.18 Common Command Group ............................................................................................ 5-62

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Contents
Chapter 6 Status Reports
6.1 Status Reports.................................................................................................................. 6-1
6.2 Status Byte ....................................................................................................................... 6-3
6.3 Standard Event Register .................................................................................................. 6-5
6.4 Extended Event Register.................................................................................................. 6-7
6.5 Output Queue and Error Queue ....................................................................................... 6-8
Appendix
Appendix 1 ASCII Character Codes......................................................................................App-1
Appendix 2 Error Messages..................................................................................................App-2
Appendix 3 IEEE 488.2-1992................................................................................................App-4
Index

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USB Interface
Chapter 1 USB Interface
1.1 Names of Parts
Front Panel
ESC
RESET
SET
CAL
PAGE PAGE
ELEMENT
1
2
3
ELEMENT
ALL
RANGE
VOLTAGE CURRENT
AUTO AUTO
DISPLAY
NUMERIC WAVE OTHERS
FORM ITEM
CURSOR
INTEGRATOR
SETUP
INPUT INFO
START/
STOP
RESET
HOLD
SINGLE
SHIFT MISC
NULL
LOCAL
KEY LOCK
FILE IMAGE
MENU
STORE
STORE SET
POWER
LOCAL key
Press this key to clear the remote
mode (controlled via communications)
and enter the local mode in which
key operations are enabled.
LCD
Rear Panel
USB
USB connector for connecting
to a PC
A connector used to connect
the WT500 to the controller
(such as a PC) using a USB
cable. For the connection
procedure, see page 1-3.

1-2 IM 760201-17E
1.2 USB Interface Functions and Specifications
You can control the WT500 from a PC using the USB interface. YOKOGAWA’s dedicated
USB connection device driver and library software (TMCTL) must be installed on the PC.
Reception Function
You can specify the same settings as those specified by front panel key operations.
Receives output requests for measured and computed data, setup data, and error codes.
Transmission Function
Outputs measured and computed data.
Outputs panel setup parameters and the status byte.
Outputs error codes that have occurred.
Switching between Remote and Local Modes
When Switching from Local to Remote Mode
Remote mode is activated when the :COMMunicate:REMote ON command is received
from a controller while local mode is active.
• The REMOTE indicator is turned ON.
• All keys except the LOCAL key are disabled.
• Settings entered in local mode are retained even when the WT500 switches to remote
mode.
When Switching from Remote to Local Mode
Pressing the LOCAL key when the WT500 is in the remote mode causes the instrument
to switch to the local mode. However, this is not possible when the :COMMunicate:
LOCKout ON command is received from the PC while Local Lockout mode is active.
Local mode is activated when the :COMMunicate:REMote OFF command is received
regardless of Local Lockout.
• The REMOTE indicator is turned OFF.
• Key operations are enabled.
• Settings entered in remote mode are retained even when the WT500 switches to local
mode.
Note
The USB interface cannot be used simultaneously with other communication interfaces (GP-IB
and Ethernet).
USB Interface Specifications
Electrical and mechanical specifications: Conforms to USB Rev.1.1
Connector: Type B connector (receptacle)
Number of ports: 1
Power supply: Self-powered
Protocol: USB-TMC
PC system supported: A controller such as a PC running Windows 98 SE, Windows
Me, Windows 2000, or Windows XP that is equipped with a USB
port as standard (a separate device driver is required for the
connection with a PC)

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USB Interface
1.3 Connection via the USB Interface
Connector and Signal Names
1
2
4
3
Pin No. Signal Name
1 VBUS: +5 V
2 D–: –Data
3 D+: +Data
4 GND: Ground
Precautions to Be Taken When Making Connections
• Connect the USB cable by inserting the connector firmly into the USB connector.
• When connecting multiple devices using USB hubs, connect the WT500 to the USB
hub that is closest to the controller.
• Do not connect or disconnect the USB cable after the power is turned ON until the
WT500 boots up completely (until the WT500 is ready for operation, approximately 20
to 30 s). If you do, the WT500 may malfunction.

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GP-IB Interface (Option)
Chapter 2 GP-IB Interface (Option)
2.1 Names and Functions of Parts
Front Panel
MISC key
Press this key to configure communications.
ESC
RESET
SET
CAL
PAGE PAGE
ELEMENT
1
2
3
ELEMENT
ALL
RANGE
VOLTAGE CURRENT
AUTO AUTO
DISPLAY
NUMERIC WAVE OTHERS
FORM ITEM
CURSOR
INTEGRATOR
SETUP
INPUT INFO
START/
STOP
RESET
HOLD
SINGLE
SHIFT MISC
NULL
LOCAL
KEY LOCK
FILE IMAGE
MENU
STORE
STORE SET
POWER
LOCAL key
Press this key to clear the remote
mode (controlled via communications)
and enter the local mode in which
key operations are enabled.
LCD
Rear Panel
GP-IB
(IEEE 488)
GP-IB connector
Connector used to connect the WT500 to the
controller (PC) using a GP-IB cable.

2-2 IM 760201-17E
2.2 GP-IB Interface Functions
GP-IB Interface Functions
Listener Capability
• All of the information that you can set with the panel keys can be set through the GP-
IB interface except for turning ON/OFF the power and setting the communication
parameters.
• Receives commands from a controller requesting the output of setup parameters,
measured/computed data, waveform data, and other information.
• Also receives status report commands.
Talker Capability
• Outputs setup parameters, measured/computed data, waveform data, and other
information.
Note
Talk-only, listen-only, and controller functions are not available on this instrument.
Switching between Remote and Local Modes
When Switching from Local to Remote Mode
Receiving a REN (Remote Enable) message from the controller when the instrument is
in the local mode causes the instrument to switch to the remote mode.
• The REMOTE indicator is turned ON.
• All keys except the LOCAL key are disabled.
• Settings entered in local mode are retained even when the WT500 switches to remote
mode.
When Switching from Remote to Local Mode
Pressing LOCAL key in remote mode puts the instrument in local mode. However, this
act is invalid if the instrument has been set to Local Lockout mode (see page 2-6) by the
controller.
• The REMOTE indicator is turned OFF.
• Key operations are enabled.
• Settings entered in remote mode are retained even when the WT500 switches to local
mode.
Note
The GP-IB interface cannot be used simultaneously with other communication interfaces (USB,
or Ethernet).

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GP-IB Interface (Option)
2.3 GP-IB Interface Specifications
GP-IB Interface Specifications
Supported device: National Instruments
• AT-GPIB
• PCI-GPIB and PCI-GPIB+
• PCMCIA-GPIB and PCMCIA-GPIB +
NI-488.2M driver version 1.60 or later
Electrical and mechanical specifications: Conforms to IEEE St’d 488-1978
Functional specifications: See table below.
Protocol: Conforms to IEEE St’d 488.2-1992
Code used: ISO (ASCII) code
Mode: Addressable mode
Address setting: The address can be set in the range from 0 to
30.
Clear remote mode: Remote mode can be cleared by pressing
LOCAL key except when the instrument
has been set to Local Lockout mode by the
controller.
Functional specifications
Function Subset Name Description
Source handshaking SH1 Full source handshaking capability.
Acceptor handshaking AH1 Full acceptor handshaking capability.
Talker T6 Basic talker capability, serial polling, untalk
on MLA (My Listen Address), and no talk-only
capability.
Listener L4 Basic listener capability, unlisten on MTA (My
Talk Address), and no listen-only capability.
Service request SR1 Full service request capability
Remote local RL1 Full remote/local capability
Parallel polling PP0 No parallel polling capability
Device clear DC1 Full device clear capability
Device trigger DT1 Full device trigger capability
Controller C0 No controller capability
Electrical characteristics E1 Open collector

2-4 IM 760201-17E
2.4 Connecting the GP-IB Cable
GP-IB Cable The GP-IB connector used on this instrument is a 24-pin connector that conforms to the
IEEE St’d 488-1978. Use a GP-IB cable that conforms to this standard.
Connection Procedure
Connect the cable as shown below.
Precautions to Be Taken When Making Connections
• Firmly tighten the screws on the GP-IB cable connector.
• Use an NI (National Instruments) model GP-IB port (or card) on the PC side. For
details, see section 2.3.
• If a converter is used along the communication cable connecting the WT and PC (for
example, a GP-IB-to-USB converter), malfunctions can occur. For details, consult with
your Yokogawa dealer or representative.
• Multiple cables can be used to connect multiple devices. However, no more than 15
devices including the controller can be connected on a single bus.
• When connecting multiple devices, each device must have its own unique address.
• Use a cable of length 2 m or less for connecting the devices.
• Make sure the total cable length does not exceed 20 m.
• When communicating, have at least two-thirds of the devices turned ON.
• To connect multiple devices, wire them in a daisy-chain or star configuration as shown
below. You can also mix these configurations. Loop configuration is not allowed.
• To connect a BNC cable to the external clock input/external start signal output connector
(EXT CLK) when a GP-IB cable is connected to the GP-IB connector, first remove the
GP-IB cable. Then connect the BNC cable. Finally, reconnect the GP-IB cable.
CAUTION
When connecting or disconnecting communication cables, make sure to turn OFF the PC and
the WT500. Otherwise, erroneous operation or damage to the internal circuitry may result.
French
ATTENTION
Lors de la connexion ou déconnexion des câbles de communication, veiller à
mettre le PC et cet instrument hors tension. À défaut, des dysfonctionnements
et/ou un endommagement du circuit interne risquent de se produire.

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GP-IB Interface (Option)
2.5 Setting the GP-IB Control
Procedure
1. Press MISC to display the Misc Menu.
2. Press the cursor keys to select the Remote Control.
3. Press SET. The Remote Control dialog box appears.
4. Press the cursor keys to select GP-IB Address.
5. Press SET. The GP-IB Address dialog box appears.
6. Press the cursor keys to select the address.
7. Press SET to confirm the address.
Explanation
Enter the following settings when using a controller to set information that can be
specified through key operation on the WT500 or when outputting setup parameters or
output waveform display data to the controller.
Address
Set the address of the WT500 within the following range for the addressable mode.
0 to 30
Each device that can be connected via GP-IB has a unique address within the GP-IB
system. This address is used to distinguish the device from others. Therefore, when you
connect the WT500 to a PC, for example, make sure to assign a unique address to the
WT500.
Note
Do not change the address while the controller or other devices are using the GP-IB system.

2-6 IM 760201-17E
2.6 Responses to Interface Messages
Responses to Interface Messages
Responses to a Uni-Line Message
• IFC (Interface Clear)
Clears the talker and listener functions. Stops output if data are being output.
• REN (Remote Enable)
Switches between the remote and local modes.
IDY (Identify) is not supported.
Responses to a Multi-Line Message (Address Command)
• GTL (Go To Local)
Switches to the local mode.
• SDC (Selected Device Clear)
• Clears the program message (command) being received and the output queue (see
page 6-8).
• *OPC and *OPC? commands in execution are void.
• The *WAI and COMMunicate:WAIT commands are immediately terminated.
• GET (Group Execute Trigger)
Same operation as the *TRG command.
PPC (Parallel Poll Configure) and TCT (Take Control) are not supported.
Responses to a Multi-Line Message (Universal Command)
• LLO (Local Lockout)
Disables LOCAL on the front panel to prohibit switching to the local mode.
• DCL (Device Clear)
Same operation as the SDC message.
• SPE (Serial Poll Enable)
Sets the talker function on all devices on the bus to serial polling mode. The controller
polls the devices in order.
• SPD (Serial Poll Disable)
Clears the serial polling mode of the talker function on all devices on the bus.
PPU (Parallel Poll Unconfigure) is not supported.
What Is an Interface Message
Interface messages are also referred to as interface commands or bus commands. They
are commands that are issued by the controller. They are classified as follows:
Uni-Line Messages
A single control line is used to transmit uni-line messages. The following three types are
available.
• IFC (Interface Clear)
• REN (Remote Enable)
• IDY (Identify)

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GP-IB Interface (Option)
2.6 Responses to Interface Messages
Multi-Line Messages
Eight data lines are used to transmit multi-line messages. The messages are classified
as follows:
• Address Commands
These commands are valid when the instrument is designated as a listener or as a
talker. The following five types are available.
• Commands that are valid on an instrument that is designated as a listener
• GTL (Go To Local)
• SDC (Selected Device Clear)
• PPC (Parallel Poll Configure)
• GET (Group Execute Trigger)
• Commands that are valid on an instrument that is designated as a talker
TCT (Take Control)
• Universal Commands
These commands are valid on all instruments regardless of the listener and talker
designations. The following five types are available.
• LLO (Local Lockout)
• DCL (Device Clear)
• PPU (Parallel Poll Unconfigure)
• SPE (Serial Poll Enable)
• SPD (Serial Poll Disable)
In addition, listener address, talker address, and secondary commands are also
considered interface messages.
Interface messages
Uni-line
messages Address
commands
Universal
commands
IFC
REN
IDY
GTL
SDC
PPC
GET
TCT
LLO
DCL
PPU
SPE
SPD
Listener
address
Talker
address
Secondary
commands
Multi-line messages
The WT1500 supports interface messages marked with a .
Note
The differences between SDC and DCL
In multi-line messages, SDC messages are those that require talker or listener designation and
DCL messages are those that do not require the designation. Therefore, SDC messages are
directed at a particular instrument while DCL messages are directed at all instruments on the
bus.

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Ethernet Interface (Option)
3.1 Names and Functions of Parts
Front Panel
ESC
RESET
SET
CAL
PAGE PAGE
ELEMENT
1
2
3
ELEMENT
ALL
RANGE
VOLTAGE CURRENT
AUTO AUTO
DISPLAY
NUMERIC WAVE OTHERS
FORM ITEM
CURSOR
INTEGRATOR
SETUP
INPUT INFO
START/
STOP
RESET
HOLD
SINGLE
SHIFT MISC
NULL
LOCAL
KEY LOCK
FILE IMAGE
MENU
STORE
STORE SET
POWER
LOCAL key
Press this key to clear the remote
mode (controlled via communications)
and enter the local mode in which
key operations are enabled.
LCD
Rear Panel
ETHERNET 100BASE-TX
LINK/
ACT
100-
LINK
Ethernet port
(100BASE-TX)
Port used to connect to the controller (PC)
via the network or by aone-to-one connection.
For the connection procedure, see section
11.2 in the User's Manual IM760201-01E.
Chapter 3 Ethernet Interface (Option)

3-2 IM 760201-17E
3.2 Ethernet Interface Functions and
Specifications
You can control the WT500 from a PC using the Ethernet interface. YOKOGAWA’s
dedicated library software (TMCTL) must be installed on the PC.
Receiving Function
You can specify the same settings as those specified by front panel key operations.
Receives output requests for measured and computed data, setup parameters of the
panel, and error codes.
Sending Function Outputs measured and computed data.
Outputs panel setup parameters and the status byte.
Outputs error codes that have occurred.
Switching between Remote and Local Modes
When Switching from Local to Remote Mode
If the WT500 receives a “:COMMunicate:REMote ON” command from the PC when it
is in the local mode, it switches to the remote mode.
• The REMOTE indicator is turned ON.
• All keys except the LOCAL key are disabled.
• Settings entered in local mode are retained even when the WT500 switches to remote
mode.
When Switching from Remote to Local Mode
Pressing LOCAL key in remote mode puts the instrument in local mode. However, this
is void when the WT500 has received a “:COMMunicate:LOCKout ON” command from
the PC (local lockout condition). When the WT500 receives a “:COMMunicate:REMote
OFF” command from the PC, the WT500 switches to the local mode regardless of the
local lockout condition.
• The REMOTE indicator is turned OFF.
• Key operations are enabled.
• Settings entered in remote mode are retained even when the WT500 switches to local
mode.
Note
The Ethernet interface cannot be used simultaneously with other communication interfaces (USB
or GP-IB).
Ethernet Interface Specifications
Electrical and mechanical specifications: Conforms to IEEE 802.3.
Number of simultaneous connections: 1
Protocol: VXI-11
For details on other specifications, see chapter 11 in the User’s Manual IM760201-01E.

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Ethernet Interface (Option)
Connecting the WT500 and the PC
For the procedure of connecting the WT500 to a PC, see section 11.2 in the User’s
Manual IM760201-01E.
Entering TCP/IP Settings
You must enter TCP/IP settings to control the WT500 from a PC using the Ethernet
interface. For the setup procedure, see section 11.3 in the User’s Manual IM760201-
01E.
3.2 Ethernet Interface Functions and Specifications