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FTB-2 и FTB-2 Pro. Руководство пользователя - часть 19

Using Your Unit and Modules in an Automated Test Environment

Standard Status Data Structure

FTB-2 and FTB-2 Pro

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SCPI Command Structure

The information presented in this section provides an overview of SCPI

programming. If you need detailed information, refer to:

 The International Institute of Electrical and Electronics Engineers. IEEE

Standard 488.2-1992, IEEE Standard Codes, Formats, Protocols and

Common Commands For Use with ANSI/IEEE Std. 488.1-1987. New

York, 1992.

 Standard Commands for Programmable Instruments (SCPI). Volume

1: Syntax and Style. Vers. 1999.0 May, U.S.A, 1999.

The provided commands follow the guidelines determined by the Standard

Commands for Programmable Instruments (SCPI) consortium. A program

message consists of one or more commands (and/or queries) with their

appropriate parameters.

For example, a program message could contain a command used to

activate or deactivate a source. The corresponding command syntax

would be:

Mandatory

Optional keyword

keywords

(in square brackets)

SOUR:POW[:STAT]<wsp><Boolean Program Data>

Keyword

Required

Parameter

separators

space

When sending a message containing the previous command, you would

actually type: SOUR:POW ON.

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SCPI Command Structure

The following table shows elements that are commonly used in the

commands or queries syntax.

Item

Meaning

[ ]

Enclose optional keywords or parameters.

Do not include square brackets in your program message.

[1..n]

Indicates that the instrument provides multiple capabilities and that you

have to specify which one you want to use. If you omit the value, the

command will take effect on the first capability.

Multiple capabilities can be found at any branch of the command tree

(root, intermediate node or terminal node).

Example: If the command is :SENSe[1..n]:CORRection:COLLect:ZERO

and you want it to take effect on the second SENSe (sensor) capability

of the instrument, you may send this:

:SENSe2:CORRection:COLLect:ZERO.

Do not include square brackets in your program message; simply enter

the number.

<wsp>

Indicates that a space is required (“wsp” stands for “white space”).

Corresponds to ASCII character codes (0 to 9 and 11 to 32, in decimal).

Do not include “<wsp>” in your program message; simply type a space.

<digit>

Element used in the construction of various numeric data types. Can

take any value between 0 and 9 inclusively (corresponds to ASCII

character codes 48 to 57, in decimal).

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SCPI Command Structure

Item

Meaning

Element used in the construction of certain data types and program

messages.

<Upper/lower

case alpha>

<Upper/lower

case alpha>

<digit>

In the diagram above,

 “<Upper/lower case alpha>” corresponds to ASCII character codes

(65 to 90 and 97 to 122, in decimal).

 “_” corresponds to an underscore character (code 95, in decimal).

< >

Text appearing between angled brackets specifies the command

parameter to be sent or the response you will receive from an

instrument.

Do not include angled brackets in your program message.

Indicates that one, and only one, value must be selected from the

available choices.

Example: If the list is 0|1, you can only select 0 or 1.

Do not include the pipe character in your program message.

{ }

Indicate that the enclosed parameters can appear 0 to n times when the

command is used.

Do not include braces in your program message.

Mandatory to separate keywords. Can be omitted at the beginning of a

program message. For example, you can use either :SYST:ERR or

SYST:ERR.

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Consulting Data Types

Item

Meaning

;

 Mandatory to separate the different commands of a program

message when more than one command is sent at a time. In this

case, it is called <PROGRAM MESSAGE UNIT SEPARATOR>.

 Also used to separate responses when multiple queries were sent in

a single program message. In this case, it is called <RESPONSE

MESSAGE UNIT SEPARATOR>.

 Mandatory to separate parameters in a command or a query. In this

case, it is called <PROGRAM DATA SEPARATOR>.

 Also used to separate the various responses from a query. In this

case, it is called <RESPONSE DATA SEPARATOR>.

There are also several conventions regarding command syntax:

 Spelling errors will cancel the command or query.

 Commands and queries are not case-sensitive. You can type your

program messages using either lower-case or upper-case letters.

 The command or query can be written using only the three- or

four-letter shortcuts, only full words, or a combination of both.

The example below shows the long and the short forms of a same

query.

:SYSTem:ERRor?

Long form

Short form (small words

:SYST:ERR?

represented by the capital letters

:syst:err?

of the long form)

Consulting Data Types

If you need information about data types used in EXFO’s documentation,

see the appendix on data types.

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Writing Remote Control Code

Your unit offers many commands permitting complete remote control of all

the supported FTB components. These commands adhere to the SCPI

standard.

You can find all the commands and queries supported by your unit in the

IEEE 488.2 and Specific Commands appendix. For information on

commands specific to particular instruments, refer to the instrument’s user

guide.

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Writing Remote Control Code

When you write code, you must follow these rules on message reception

and transmission:



The controller must have sent a complete message to the instrument

(including the message terminator) before retrieving a response.



The controller must retrieve all the responses from previous queries

(including the response terminator) before sending a new message to

an instrument.



The controller must not try to retrieve a response from an instrument if

the corresponding query has not been previously sent to the

instrument.



You must pay special attention to queries that return an indefinite ASCII

response. To avoid any confusion, the IEEE 488.2 standard requires that

this data type be immediately followed by a response termination

character. For this reason, when working with compound queries, you

must ensure that a query sending an indefinite ASCII response is the

last query of the series.



Be careful when sending program messages containing multiple

queries that return large amounts of data. Since the controller can only

retrieve data when the instrument has finished processing the queries,

it could result in problems ranging from a saturation of the output

queue to the complete blocking of the whole system.

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Error Message Format

System and device-specific errors are managed by your unit. The generic

format for error messages is illustrated in the following figure.

<Device

<Error

dependent

number>

description>

;

information>

As shown in the above figure, the message contains three parts:

 error number

 error description

 device-dependent information

Error messages ending in a negative number are SCPI-based errors.

For a complete list of possible errors, see the appendix on SCPI-based

errors.

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Monitoring Remote Commands

ToolBox X allows you to monitor remote commands sent to your units, if

desired.

To monitor remote commands:

1. From the main window, tap the Test Tools button.

2. Depending on which type of communication protocol you are using,

select IC Monitor or SCPI Telnet Monitor.

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Monitoring Remote Commands

3. Do one of the following:

 If monitoring using ActiveX or RS-232, click Connect to IC.

Connection

information

Incoming

commands

You are automatically connected to the monitoring system. The

Disconnect from IC button becomes available for you when you

are ready to disconnect.

Once connected, your current connection information will appear

in the upper part of the window, and the commands will appear as

a list in the lower part of the window.

With the History parameter, you determine how many commands

you want to keep in the list. You can change the number by using

the arrow buttons on each side of the list.

To clear the history, click

To view the list in any word processor, click

to copy it to the

clipboard, and then paste it in your document. You can use any

program, as the list is copied in text format.

To exit the monitoring utility, click Exit.

For more information, see the section on using your unit in an

automated test environment.

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Monitoring Remote Commands

 If monitoring using TCP/IP, which provides sending SCPI

commands over TCP/IP through Telnet from the EXFO Instrument

Control, you are automatically connected to the monitoring

system.

Note: Port 5024 is designated for sending SCPI commands in the Telnet protocol.

Connection tabs

List of connections

Once connected, your current connection information will appear

in the All Connections View tab, and the commands will appear as

a list in the lower part of the window.

The Disconnect button becomes available for you to click when

you are ready to disconnect.

Connection information is also displayed in a separate tab,

identified by its IP address, from where you can monitor the

commands and other actions sent through TCP/IP over Telnet, as

well as the results.

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Monitoring Remote Commands

With the History parameter, you determine how many commands

you want to keep in the list. You can increase or decrease the

number by using the arrow buttons on each side of the list.

To clear the history, click Clear.

To view the list in any word processor, click Copy to copy it to the

clipboard, and then paste it in your document. You can use any

program, as the list is copied in text format.

To save the list as a file, click Save.

To exit the monitoring utility, click Exit.

For more information, refer to the user documentation about

communication through TCP/IP over Telnet.

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FTB-2 and FTB-2 Pro

Техническое обслуживание

Для обеспечения продолжительной безотказной работы необходимо

соблюдать перечисленные ниже требования:

 Перед началом работы всегда обследуйте волоконно-оптические

разъемы и, при необходимости, очищайте их.

 Не допускайте попадания пыли в устройство.

 Очищайте корпус устройства и переднюю панель тряпкой, слегка

смоченной водой.

 Храните устройство при комнатной температуре в чистом и сухом

месте. Не допускайте попадания прямых солнечных лучей на

устройство.

 Не подвергайте устройство воздействию повышенной влажности и

значительным колебаниям температуры.

 Берегите устройство от ударов и сотрясений.

 В случае попадания жидкости на поверхность или внутрь

устройства немедленно выключите питание, отключите устройство

от всех внешних источников питания, извлеките аккумуляторы и

дайте устройству полностью высохнуть.

ВНИМАНИЕ!

Использование средств управления, настроек и процедур, в

частности, эксплуатации и технического обслуживания,

отличных от указанных в данной инструкции, может привести к

возникновению опасного радиоактивного излучения, а также к

ослабеванию уровня защиты, который обеспечивается для

данного устройства.

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Техническое обслуживание

Очистка портов детектора

Регулярная очистка детекторов позволяет сохранять точность

измерений.

ВАЖНО!

Всегда накрывайте детекторы защитными колпачками, если

устройство не используется.

Для очистки портов детекторов выполните следующие действия:

1. Снимите защитный колпачок и адаптер (FOA) с детектора.

2. Если на детекторе имеется пыль, удалите ее струей сжатого

воздуха.

3. Не касаясь мягкого кончика чистящей палочки, смочите ее одной

каплей изопропилового спирта.

ВАЖНО!

Если использовать чрезмерное количество спирта, могут

остаться следы. Не используйте бутылки, из которых сразу же

выливается слишком много спирта.

4. Немного надавите (так, чтобы не повредить окно детектора) и

легкими движениями вращайте чистящую палочку на окне

детектора.

5. Повторите шаг 4, используя сухую чистящую палочку или струю

сжатого воздуха.

6. Выбрасывайте чистящие палочки после однократного

использования.

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Очистка разъемов типа VFL

Разъемы VFL зафиксированы на вашем устройстве и могут быть

очищены с помощью механического очистителя.

ВНИМАНИЕ!

Осмотр поверхности разъема с помощью оптоволоконного

микроскопа ПРИ ВКЛЮЧЕННОМ УСТРОЙСТВЕ ПРИВЕДЕТ к

долговременной травме глаза.

Для очистки разъема с помощью механического очистителя

выполните следующее:

1. Введите очиститель в оптический адаптер и вдавите внешнюю

оболочку в очиститель.

Примечание:Очиститель издаст щелчок в качестве сигнала о завершении очистки.

2. Проверьте поверхность разъема с помощью портативного

микроскопа для оптоволокна (например, EXFO FOMS) или зонда

для осмотра оптоволокна (например, EXFO FIP).

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Техническое обслуживание

Очистка сенсорного экрана

Для очистки сенсорного экрана используйте мягкую неабразивную

ткань, например используемую для очистки очков для чтения,

смоченную в воде.

ПРЕДОСТЕРЕЖЕНИЕ!

Использование любых отличных от воды веществ может

повредить специальное покрытие устройства, оснащенного

специальным экраном для наружного использования (опция

S2).

EXFO рекомендует использовать прилагающуюся защитную пленку,

когда никто не работает с устройством.

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