LeCroy 7200A Programmer's Guide

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1-1

GPIB Signals and Lines

,!*

GPIB Remote Control

The General Purpose Interface Bus (GPIB) te originally based on the IEEE Standard 488, 1976 (and later revised

IEEE 488.1,1987).

The GPIB can interconnect many instruments to allow communication with one another over shared cables. The GPIB uses a bit-parallel, byte-sedal format. The 7200A can achieve a

maximum transmission rate of 400 kBytes per second.

A device connected to the GPIB is either a talker, listener, or controller. Although some devices can change roles, a device can perform just one role at a time.

Talker Places messages or data on the network for transmission to

other devices. Only one device on the network can be ithe talker.

Listener

Receives data or commands over the network. Several listeners may be active at one time.

ControIIer,,~;

ei: ¯

Governs the operation of the network. A controller, usually a

computer, normally sends program messages to devices and receives response messages from them. One controller task is to decide which device is the talker and which is a listener(s). The

controller may assign itself to be the talker at one time, and a listener at other times. If devices on the network never change their roles, a controller is not required.

The Communications Screen allows you to select GPIB as the Remote Control port and set

the GPIB address for the 7200A. The Hardcopy screen allows you to select GPIB as the

hardcopy port for printers and plotters. If GPIB is the selected port for hardcopy, no controller is needed and all other devices on the bus must be in =Listen Only" mode.

GPIB Signals and Lines

The GPIB has 16 signal lines and eight ground return lines. Eight of the 16 signal lines form a bi-directional data bus which transfers data and commands. The remaining eight signal lines control the bus operation. Three lines are for handshake signals which synchronize

data transmission. The remaining five are management lines which control the flow of information across the interface.

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GPIB Host and Hardcopy Operation

Setting the GPIB Address

The GPIB address is set in the Communications screen. From the Main Screen, press the Configure System softkey to display the Configure System setup screen. Then press the Communication Setup softkey to display the Communications Setup screen. Move the box

onto the =Remote Control from" field and select GPIB. Then move the box onto the =GPIB Address" field and select an address from 0 to 30.

GPIB Host and Hardcopy Operation

The 7200A can communicate across GPIB as a talker or a listener with a remote host controller to receive remote commands/queries and send responses. For this talker/listener remote control operation, the 7200A conforms to the guidelines specified by IEEE 488.2. The hardcopy output can also communicate across GPIB in one of two ways. First, if the hard-

copy port is the same as the remote control port, then a remote hardcopy command sends

the output to the remote host as a query response. Second, if the hardcopy port is different from the remote control port or and the local hardcopy key is pressed, then the 7200A enters Talk Only mode and does not expect any controller present on the bus~ ~ ::

Remote Control Operation over GPIB ....

Talk/Listen The 7200A enters this mode when the =Remote Control from"

field in the Communications Setup screen is set to GPIB. In this

mode, the 7200A can both receive commands and setups from

the remote host computer and send data and measurement resuits.

~ :

~ .~ ¯

Hardcopy Operation over GPIB

Talk Only To output hardcopy data over GPIB, the =Hardcopy Port" field in

the Hardcopy screen must be set to GPIB. Setting the Hardcopy Port has no effect on the selected port until the hardcopy is initiated. If the Hardcopy Port is GPIB, then pressing the local Hardcopy key will force the 7200A to enter Talk Only mode. Also, if the Hardcopy Port is GPIB and the Remote Control port is RS-

232-C, then initiating a hardcopy remotely from RS-232-C will also force the 7200A to enter Talk Only mode. Talk Only is a spe-

cial GPIB mode where there is no controller allowed on the bus;

the 7200A is the only talker and all connected devices must be

listeners (ie., printers/plotters must be in Listen Only mode). However, if both the hardcopy port and =Remote Control

from" field are set to GPIB, then pressing the local Hardcopy key

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GPIB Host and Hardcopy Operation

just sets the User Request (URQ) bit in the Standard Event

Status (*ESR) register, the 7200A cannot enter Talk Only mode since this may disrupt the conb’oller. Instead, the controller may

query the *ESR register and if the URQ bit is set, the controller may halt bus activity and synchronously initiate a remote Hard-

copy as describes next.

Talk/Listen

When both the Hardcopy Port and the Remote Control port are set to GPIB, then sending the remote command "HARDCOPY"

or "HCPY" over GPIB from the host computer will cause the 7200A to send the hardcopy output to the host computer as a re-

sponse message. In this mode, the 7200A will wait to be addressed to talk before sending the hardcopy data. The host

computer then has three options in generating the hardcopy:

1) The host computer may read the data into Internal memory and then send the data to a printer/plotter. This is exactly the same as reading a query response.

2) The host computer may send the =HARDCOPY" remote command and then address the printer/plotter to listen and the

7200A to talk and read the data from the 7200A. As the data is

read into the computer’s internal memory, it is also printed/plot-

ted to the printer/plotter which is a Listener.

3) The host computer may send the "HARDCOPY" remote com-

mand and then address the printer/plotter to listen, the 7200A to talk, and the controller to go into stand-by mode waiting for EOI. Altematively, the Data Processing Status Register (DPR) could be programmed to issue an SRQ when hardcopy is complete so that the host computer can perform other tasks while the hardcopy is performed.

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GPIB Host and Hardcopy Operation

GPIB

RS232

RS2.32

Centronics

Floppy

GPIB

RS232

GPIB

GPIB/

RS2.32 RS232/

GPIB

Sets the URQ bit in the *ESR register.

Hardcopy data output in

Talk-Only mode. Address the device at address 30

to listen before sending data.

Sets the URQ bit in the *ESR register.

Hardcopy data is output immediately.

Hardcopy data is written to a floppy disk immediately.

Hardcopy data output when the controller addresses the 7200A to

talk.

Hardcopy data output in

Talk-Only mode. Address the device at address 30

to listen before sending data.

Hardcopy data output when controller asserts

CTS (Hardwire mode) until receipt of XOFF.

Hardcopy data is output immediately.

Hardcopy data is output

immediately.

Hardcopy data is written

to a floppy disk

immediately.

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GPIB Device Interconnections

The devices on the GPIB network may be connected in any combination of star or linear ar-

rangements (Figure 1.1 ). Standard IEEE 488.2 cables must be used to connect all the de-

vices and total length must not exceed 20 meters. The devices must conform to these rules:

¯ At least half the devices on the network must be turned on. ¯ One network can connect no more than 15 devices (including the controller).

One device must be connected for every two meters of cable, assuming one

device presents one standard device load. The 7200A’s GPIB connector is located on its rear panel.

Each device must have a unique bus address.

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OL=VtC;E A

DL=VlCE D

DEVICE B

DEVICE C

I I EC

STAR CONFIGURATION LINEAR CONFIGURATION

Figure 1.1 : Examples of GPIB Network Arrangements

RS-232-C Remote Control

The 7200A interface is defined by the following GPIB function codes:

For a description of these functions and their subsets, see IEEE Standard 488.1, Section 2.2 through 2.12.5. The IEEE Standard is published by the Institute of Electrical and Electronics Engineers, Inc., 345 East 47th Street, New

York, New York 10017.

INTERFACE FUNCTION

Controller (CO) Source Handshake (SH1) Acceptor Handshake (AH1)

Talker (T6) Listener (L4)

Service Request (SR1) Device Trigger (DT1)

Device Clear (DC1) Parallel Poll (PP0)

Remote Local (RL1) Electrical Interface (E2.)

*Unaddress refers to the action taken when the interface switches its function. This action effectively clears the current function before the

next function is selected.

Table 1.1: 7200 IEEE-488 Function Codes

RS-232-C Remote Control

No controller capability. Complete source handshake capability. Complete acceptor handshake capability

Basic talker with serial poll capability and unaddress* if MLA (My Listen Address). Basic listener with unaddress if MTA (My

Talk Address). Complete serial poll capability. Capable of responding to device trigger.

Responds to device clear (universal or

selective). No parallel poll capability Complete remote/local capability

SRQ, NRFD, and NDAC are tri-state lines

The 7200A can also be operated from a computer or terminal via its RS-232-C port. RS-232C uses serial transmission and complies with the Electronic Industries Association’s RS-232-

C standard. (The equivalent international standard is ISO V24 which is generally compatible with the RS-232-C version.)

Unlike the GPIB where many devices can be interconnected, the RS-232-C connects just two devices. Only three communication lines are necessary to establish the interface: trans-

mired data, received data, and logic ground. However, the additional lines, RTS (request to send) and CTS (clear to send), permit transfer of data only after confirming that the receiving

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RS-232-C Configuration

device is capable of accepting more data. That is, the sender sends an RTS and waits for a CTS from the receiver before sending data. This protocol guarantees that data does not over-

run the receiver’s buffer. RS-232-C offers compatability with most computers. It uses a bit-serial data format with a

maximum transmission rate of 19,200 bits per second, much less than that of GPIB. Each data word is transmitted as a separate packet with its own start and stop markers, or

bits. The RS-232-C standard defines the electrical characteristics of these bits and the composition of each packet. Their composition and transmission rate must be the same for both

the device and the 7200A. The Communications Setup screen is used to select transmission rate, error checking (parity), and number of stop bits. In order to establish communications, additional serial transmission characteristics may be set remotely using the COMM_RS232

remote command. See Section 5: Communication Commands for a description of this command.

RS-232-C Configuration

Setup the Serial Port

The 7200A contains a 9-pin, male RS-232-C connector for serial communication with a

printer, terminal, or computer. To connect an RS-232-C line to the 7200A, use a female DB9-

D connector. If the computer has a DB25-D connector, use a DB9-D to DB25-D cable adapter. The optional CTS and RTS handshaking guarantees that data passed between a remote computer and the 7200A will not overrun the 7200A or the computer’s RS-232-C buffer.

Select the desired settings for the interface using the Communications Setup screen:

1. From the Main Screen, press the Configure System softkey to display the Configure System setup screen.

2. Then press the Communication Setup softkey to display the Communications Setup screen.

RS-232-C Host lnterconnection

Although the RS-232-C standard defines signal lines and electrical characteristics, it does not define mechanical characteristics. The 7200A RS-232-C output port is configured as an

RS-232-C Data Terminal Equipment so that data is sent from pin 2 and received on pin 3. For remote operation, the RS-232-C port must be connected to a computer terminal.

The following diagrams are used for various host drivers.

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RS-232-C Configuration

"Data Communication Equipment"

(7200A)

"Data Terminal Equipment"

Figure 1.2: RS-232-C Connection to an IBM-PC Host

DB9 to DB25 Wiring

This wiring configuration is used for IBM-PCs and compatibles with DB25-D connectors configured as Data Terminal Equipment¯ Note that for XON-XOFF communication protocol,

only pins 2, 3, and 5 on the DB9-D connector are needed¯ Also, commercially available DB9to-DB25 adapter cables for the IBM-PC swap pins 2 and 3 and pins 7 and 8.

7200A (DB9, DTE)

Pin 2 Pin 3 Pin 5

If Hardwaire handshaking is used (see "Communications Setup,

page 3-119"), the following connections must also be satisfied.

Pin 7 Pin 8

Computer

(DB25, DTE)

Tx Pin 2 Rx

Gnd

CTS

RTS Pin 4

Pin 3 Pin 7

Pin 5

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RS-232-C Configuration

DB9 to DB9 Wiring

For IBM PC-AT types with DB9-D connectors configured as Data Terminal Equipment.

7200A Computer (DE9, DTE) (DB9, DTE)

Pin 2 Pin 3 Pin 3

Pin 5

If Hardwaire handshaking is used (see "Communications Setup, page 3-131"), the following connections must also be satisfied.

Pin 7

Pin 8 --~,

Gnd

CTS

Pin 2

Pin 7

Pin 5

Pin 4

DTE to DCE Wiring

For non-IBM types with DB9-D connectors configured as Data Communications Equipment.

7200A Computer (DB9, DTE) (DBg, DCE)

Pin 2 Pin 3 Pin 3

Tx Rx

Pin 2

1-10

Pin 5

If Hardwaire handshaking is used (see "Communications Setup, page 3-131"), the following connections must also be satisfied.

Pin 7

Pin 8 Pin 8

Gnd

CTS Pin 7

Pin 7

RS-232-C Configuration

RS-232-C Interconnections for Hardcopy

When connecting an RS-232-C serial printer/plotter to the 7200A, the printer/plotter configu-

ration must match the 7200A RS-232-C port settings. To modify settings, use the Communi-

cations Setup screen.

RS-232-C Connection

=Data Terminal Equipment"

=Data Communication Equipment"

(7200A)

Figure 1.3: RS-232-C Connection to an RS-232-C

Serial Plotter

DB9 to DB25 Wiring

NOTE: The 7200A RS-232-C interface is a DB9-D connector. Use an adapter cable to connect to an RS-232-C DB25-D connector.

Pin2

Plot I Pin4

Pin8 Pin8

PIn 7

~n2

~n8

~n7

Pin4. Pin5

Pin6

Pin 20

Pin 8

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RS-232-C Host Operation

Parallel-Centronics Wiring

The 7200A uses a standard DB25-D female connector as the Centronics parallel output port. An adaptor cable is required to adapt the 7200A DB25-D connector to the standard 36-pin

bail lock connector used on most Centronics printers.

7200A ~

Printer

Figure 1.4: Output to Centronics type Printer/Plotter

RS-232-C Host Operation

The 7200A may be controlled by a Remote Host computer in a similar manner as in GPIB. It is able to accept commands, strings, and arbitrary block data and send back responses to queries. However, RS-232-C communications is limited to the transfer of ASCII characters

in the range 1 to 127. Also, any character whose value is below a <space> (ASCII 32) can not be used as part of a valid command or query but may be used as a valid <PROGRAM MESSAGE TERMINATOR>. The exception to this rule is the <ESCAPE> character (ASCII

27). When <ESC> is sent to the 7200A, the very next character sent is interpreted to have special meaning.

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The valid Escape sequences are as follows:

RS-232-C Host Operation

Command <ESC>( <ESC>)

<ESC>[ <ESC>] <ESC>C

<ESC>R <ESC>L

<ESC>F <ESC>T

All <ESC> commands are immediately executed upon being parsed. Their intent is to simulate GPIB commands over the serial port.

When the 7200A receives ASCII block data in excess of its input buffer size it will send XOFF (ASCII 19) to hold up the transfer of data from the Remote Host until it has processed

the current buffer. Also, if the handshake mode is HARDWlRE, it will de-assert CTS (Clear To Send). When the 7200A is ready for more data, it will send XON (ASCII 17) and assert CTS.

Descriptiorl Selects HARDWIRE handshake mode Selects XON-XOFF handshake mode

Selects Echo off (half-duplex mode) Selects Echo on (full-duplex mode)

Sends a DCL (device clear) command

Sends a REN (remote enable) command Sends an LCL (local enable) command Sends an LLO (local lockout) command Sends a GET (group execute trigger) command

Table 1.2: Valid Escape Sequences

For a complete description of setting the configurtation of the RS-232-C port for Remote

Host communications, see the COM_RS232 remote command in Section 5 (Communication Commands).

1-13

Section 2: Command S ntax

The following segments describe the rules and syntax for controlling the 7200A from a remote computer over either GPIB or RS-232-C. Any differences between the ports are noted.

Message Types

Commands

Responses

Waveforms

Status

With few exceptions, all commands, responses, and status messages are encoded accord-

ing to the American Standard Code for Information Interchange (ASCII) and are strings

printable characters. Upper and lower case characters are interchangeable.

Commands have two categories: action and query.

An action command causes the 7200A to make an assignment or perform a function. For example, it might cause the 7200A to calibrate all the plug-ins, or an assignment may result in a new front panel setting, a communication parameter receiving a new

value, or the date being set. Commands that request results are called queries. They ask the

7200A to return waveform data, settings, or measurements. These are replies sent from the 7200A in response to query com-

mands.

Waveform data is a special form of response. It may be output in

binary or hexadecimal formatted blocks. These formats are more

compact than that used for response messages, so a large number of data points can be transferred in less time.

A status message indicates the 7200A’s current internal state.

2-1

Command Processing

Message Direction

As shown in Figure 2.1, the controller sends commands to the 7200A, and the 7200A sends waveforms, responses, and status

messages back to the controller.

Controller

Action and Query Commands

Waveforms

Responses

Status

Figure 2.1: Message Directions

7200A

Command Processing

Commands are not processed until the 7200A receives an <end>, or, in the case of waveform input, when the 7200A input buffer is full (i.e., normally, no action is taken on any part of a command message until the entire message is received or the message size exceeds the input buffer size).

Command Processing Order

Valid commands are processed in the order they are received.

Some remote commands cannot be performed immediately. For example, it is not possible to read channels that are armed and waiting for a trigger, since the memories associated

with these channels are continuously being written. If the 7200A receives a command it cannot perform immediately (another example is the STORE of a channel), it defers executing the command until the needed waveform is acquired.

2-2

IEEE-488 Standard Messages

Command Errors

Before attempting to execute a command or query, the 7200A confirms that all the required

parts of the command are provided, and that all the arguments are within required ranges.

If an error is generated, the 7200A will set the appropriate status and, if enabled, report it to

the host computer. The host can then interrogate the status byte(s) to determine the nature of the error. Refer to Section 4 for details on status bytes.

NOTE: Commands preceding and following an error in multi-command messages are still executed. This provides

consistent operation whether commands are sent one at a time or several per message.

Output from the 7200A

When the 7200A generates a response to a query, the controller should read it before sending a second query. If the controller sends a second query before reading the response to

the first one, the 7200A interprets this as an Interrupted Action and performs the following:

1. Upon receiving the <end> of the second query, the 7200A flushes its output buffer of all responses to previous queries.

2. The 7200A sets a Query Error bit, and

3. The 7200A fills the output buffer with the response to the second query.

IEEE-488 Standard Messages

This section explains how the 7200A reacts to the Standard 488.2 messages.

NOTE: This section pertains to GPIB only

Serial Poll Function The 7200A implements a full Serial Poll Interface Function:

1. It can assert the SRQ (Service Request) control line.

2. It will respond with the current serial poll byte or STB when addressed to Talk and after the Serial Poll Enable interface

message is received.

3. After transmitting its status message, the 7200A stops assert-

ing the SRQ line and clears its internal status byte.

Receiving the Trigger

Message

The 7200A responds to the Trigger message [Group Execute Trigger (GET) or the *TRG command] by arming all plug-ins. The trigger signal, also available on the rear panel, can be used

2-3

IEEE-488 Standard Messages

for external hardware or event synchronization to internal 7200A operations. It is executed after all previously received commands

have been processed.

Interface Clear

Device Clear (Sdective or Universal)

Go to Local, Go to Remote, Go to Remote with Lockout Local

The Interface Clear message (asserting IFC line) is an asynchronous control line that causes all bus activity to halt. When the

7200A receives the IFC message, it becomes unaddressed, stops talking or listening, and will not participate in future bus

transactions until readdressed to talk or listen.

The 7200A will respond to a Selective Device Clear or a Univer-

sal Device Clear interface message. The former requires that the 7200A first be addressed to listen, followed by the Selective Device Clear message. The latter does not require that the instru-

ment be previously addressed to listen. Device Clear causes the input buffer, the output queue, and the message available (MAV) status bit to be cleared.

The 7200A can operate in Local or Remote mode. In Local mode, all front panel controls are operational and commands

from the host computer will also be processed. In Remote mode, the 7200A operates under computer control and no front panel

controls are operational except the Local softkey (if enabled). (The 7200A always powers on in Local mode.)

NOTE: The 7200A processes all messages regardless of being in Remote or Local modes.

The 7200A switches to Remote mode (with Local softkey enabled) when the 7200A receives the command "REM", or a com-

mand is sent with the REN line asserted. All instrument settings remain unchanged during local-to-remote transitions. The lower left part of the 7200A screen indicates that Remote mode is enabled and the Local softkey appears. No other front panel controis operate.

2.4

If the 7200A is under remote control and the Local softkey is pressed, the instrument interrupts program control and returns to

local control. Data and/or settings can now be changed locally.

CAUTION: To prevent a transition back to local mode the 7200A

can be placed in a Local Lockout state using the "LLOK" command. in Local Lockout state, all front panel keys and knobs are

IEEE-488 Standard Messages

disabled. Once Remote with Local Lockout is set, it can only be cleared when the 7200,4 is put into Local mode by sending the =L OC" command or readdressing the 7200A with REN deas-

serted.

Message Syntax

Messages consist of one or more data bytes which are sent over the bus. All messages sent to and received from the 7200A are formed of English words except for

waveform transfers. Abbreviations, typically two to four characters, are also defined to achieve higher throughput. Lower or upper case alphabetic characters are interchangeable.

NOTE: Any message received by the 7200A must conform to IEEE-

488.2 syntactic requirements. (If a violation is detected, the 7200A will generate an error which indicates an invalid command.) The

syntax for each type of message is described below.

Action Command Syntax

Commands are sent to the 7200A to initiate various actions. They contain Headers, sometimes an Argument(s), and a Terminator:

Header Identifies what action to take; e,g., set the date, stop acquisition.

Ar~nt(s)

Terminator

Qualifies or supplements the header. The argument acts as a parameter(s) or data to the header. It is included in the command

only if a header is defined to require an argument(s). For example, an argument indicates what date to set.

Indicates the end of the command message. GPIB and RS-232-C have different message terminators. In this manual,

the command message terminator is represented by <end>.

2-5

IEEE-488 Standard Messages

Space

mnemonic ~j_

’ Long Form

mnemonic

, Short Form

HEADER

Figure 2.3: Action Command Syntax

Unless specifically noted, white spaces (ASCII 32 decimal) between the parts of a command

do not affect its processing. Upper and lower case characters are interchangeable. The general format of a command follows:

Command Header

PREFIX I

Plug.in channel

2-6

Figure 2.2: Command Header

Command Arguments

IEEE-488 Standard Messages

--~ Numeric

’ ’ String ~

Figure 2.4: Command Arguments

Query Syntax

The Syntax of a Query is very similar to that of an Action command. A Query command adds a question mark (=?") immediately after the last character of the header. For example, to find

the current value for the offset on channel 2 of plugin B, send: B2:OFFSET?.

NOTE:Many action commands have a corresponding query command which may have

arguments.

Figure 2.5: Query Syntax

2,-7

IEEE-488 Standard Messages

Multiple Commands

A message containing more than one command before the terminator is called a compound, or multiple command message.

Sending a multiple command increases throughput. Each command (header and any arguments) is separated from the following one by a semicolon (";"). Space(s) on either side

the semicolon do not affect processing. Upper and lower case characters are interchangeable.

ACTION 1

COMMAND -

QUERY 1 "

COMMAND

Figure 2.6: Multiple Commands

A multiple command can include Action and Query commands. For example, one multiple command can perform auto setup, request the current time and date being used, and execute a trigger command as follows:

ASET; DATE? ; *TRG <end>

2-8

IEEE-488 Standard Messages

Command Header

A command header defines the action to perform. The header begins with a letter and can be followed by any combination of up to 15 letters, numbers, and underscores. Any com-

mand with more than four characters has a short form. (Long and Short form headers can be intermixed.) Using the short form (four or less characters) increases throughput. The long

form, however, makes understanding program code easier. For example, to set the timebase remotely, either TIME DIV or TDIV can be sent.

Command headers comprise three broad categories according to their syntactic make-up:

Directed Header, ¯ System Header, and ¯ Standard Header.

Directed Header

This type of header directs an action at an object. The object can be either a plug-in, chan-

nel, trigger source, or trace. The prefix identifies the object being acted upon. It is followed by a colon (=:") and the header which indicates the action performed.

prefix:header

Only one prefix is permitted per header.

NOTE: If a command is defined as having a prefix, the prefix must always be specified.

The types of prefixes are: Mug.in The plug-in is identified by location. The mainframe plug-in slot

nearest the display is slot A. Slot B is to the right of A. Use the plug-in prefix on/ywhen a command operates on the

plug-in controls, such as when setting the timebase. To set the timebase to 5 msec per division for the plug-in in slot A, for example, use the command:

A:TIME_DIV 5ms

2-9

IEEE-488 Standard Messages

Channel

Source

The input channel is identified by its location in the plug-in. The uppermost left BNC connector in plug-in A is labeled AI. The next lower connector is A2, and so on. To modify all channels,

do not specify a specific channel.

Use the channel prefix only for commands which affect vertical amplifiers, such as when setting the vertical sensitivity. To set the vertical sensitivity to 5 mV per division for plug-in A, channel 1, for example, use the command:

A1 :VOLT_DIV 5mV To set all of the plug-in’s channel settings to be the same, use

the plug-in prefix with no channel designation. For example, to set offset to 10 mV for all channels, use the command:

A:OFST 10 mV

Since a rigger command can specify settings for each trigger source, it must be specified as a prefix. The prefix symbols are either:

An input channel as previously defined; Plug-in and =EX" for the external trigger signal; Plug-in and =EX10" for the external tdgger signal divided by

ten; or Plug-in and =LINE" for triggering on the power line frequency.

2-10

Trace

To set the trigger level to 5 mV per division for the external trigger signal divided by ten, for example, use the command:

AEX10:TRIG_LEVEL 5mV

Traces 1 through 8, indicated as T1 through T8, define the processing and display characteristics of traces. For example, to query the horizontal position of trace 7 use the command

T7:HOR_POSITION?

IEEE-488 Standard Messages

System Header

This type of header indicates an action that affects general oscilloscope operation; that is, an operation not necessarily restricted to a particular plug-in, channel, or trace. Examples are changing the grid selection and cursor type. The System Header format disallows a prefix.

For example, to turn on local display processing, use the command:

DISPLAY_ON

Standard Header

This type of header indicates a command that is explicitly required by the IEEE-4882 standard. These commands have the same format as the System Header, except an asterisk ("*")

immediately precedes the first letter of the command. For example, the *RST command initiates a device reset, *IDN? asks the device for its identification.

Command Argument(s)

A command argument(s) qualifies or supplements the header. It is included in the command only if a command is defined to require an argument(s). For example, an argument indicates

what value to set for volts per division.

Most commands require one or more arguments to describe a desired action in detail (see Figure 2.4). The first argument is separated from the header by one or more spaces. Argu-

ments are separated from each other by commas.

The possible types or arguments are:

Decimal Numeric Any number in numeric repesentations NR1, NR2, or NR3 as de-

fined by ANSI X3.42-1975. These refer to integers (e.g., -45),

floating point (e.g., 3.1443), or exponential values (e.g.,

3.1459E+00), respectively. The ASCII characters "E" or "e" are used to delimit the mantissa

from the exponent in exponential arguments. Spaces are allowed between the exponential delimiter and the digits (0 through 9), but are not allowed between digits, or between the decimal point (.) and the digits.

Numeric values with fractional parts must be expressed as a floating point or an exponental value. For example, 3.14159 and

3.14159E+00 are both acceptable standard formats.

2-11

IEEE-488 Standard Messages

The allowable range depends on the command. If a numeric is sent to the 7200A and has a precision greater than allowed, the

7200A will truncate, process the result, and generate a warning. If a numeric not included in the specified set is sent, a valid numedc closest to that sent is used. For example, vertical position

must be specified with a value that is a multiple of 0.02. If 68.01

were sent, 68.00 is used.

Suffixes can replace exponential notation. For example, these

commands are equivalent:

TIME_DIV 5.00E-6 TIME_DIV 5.00 US

Valid suffixes are listed in the following table:

Allowed<Suffix Mult.>Mnemonics

Definition Mnemonics

1E18

EX 1E15 PE 1E12 T 1 E9 G 1 E6 MA

1E3 K 1E-3 M 1E-6

1E-9 N 1E-12

P 1E-15 F 1E-18 A

NOTE: Only engineering unit multipliers

are allowed.

Table t~cen from ANSI/tEEE SId 488,2-1987

Table 2.1: Valid Suffix Mnemonics

2-12

IEEE-488 Standard Messages

Non-Decimal Numeric

String

Numbers can also be used in bases other than base 10. For example, each bit in a status byte may be understood better if the byte is specified in hexadecimal or binary.

Precede non-decimal arguments with a pound sign ("#") followed by an "H" for hexadecimal, "Q" for octal, and "B" for bi-

nary. Note that numbers are treated as unsigned with an implicit radix point. For example, #HFF and #B11111111 are both 255.

Some commands require or allow String arguments such as

"ON" or "OFF". These arguments contain 7-bit ASCII alphanu-

meric characters. A string begins with an alpha character which may be followed by alphanumeric characters A through Z, a

through z, 0 through 9, and =._". Carriage return or line feeds are

not valid characters. Note that the oscilloscope treats upper and lower case characters identically.

Each command definition specifies the maximum number of

characters for its string argument(s). Quoted strings are delimited by either an apostrophe (’) or a quo-

tation mark (=). The 7200A returns quoted strings with quotation marks. The same type of delimiter that opens a quoted string

must close it. Strings within strings are allowed as long as each string has the same opening and closing delimiters.

Waveform Data

A quoted stdng may not be terminated with an <end> character. For example, "test <end> is an invalid string.

The WAVEFORM command lets you send or read a complete waveform. The waveform usually contains a very large amount of data. Due to its length, a special formatting convention is used to transfer the large data blocks. See page 2-17 "Waveform Data Syntax" for an explanation of this format.

2-13

IEEE-488 Standard Messages

Keywords

Some commands have several arguments. For example, the command for configuring a hardcopy device can have up to ten arguments that set such characteristics as plotter speed and paper size. Rather than listing every argument when only a few need changing, the argu-

ment specified is identified by a =keyword".

A keyword is a character argument that must be followed by a comma, and then an associated value for the characteristic being set. The value may be one of the four types of arguments previously described.

Arguments not specified remain unaffected. For example, the INTENSITY command is used to program the brightness of the traces and

grids independently. To set the grid’s intensity to half scale, send: INTENSITY GRID,,50. The

trace intensity remains unchanged.

For commands with several keywords, the order of the keyword-value pairs does not matter.

NOTE: A multi-argument command that does not use keywords must have all its arguments listed, and ordered in the same sequence as shown in the command definition.

An example of a command with no keywords is the date command, which requires specifica-

tion of the day followed by the month, etc. When querying most keyword commands, you can give the keyword(s) as an argument. For

example, CRST? HABS, VABS returns only the absolute horizontal and vertical cursor posi-

tions. If no argument is specified, all values are returned.

Command Terminators

Commands sent one at a time must end with a terminator. In this manual, terminators are indicated by <end>. Alternatively, multiple commands can be sent together by terminating

each command with a semicolon and terminating the entire multiple command message with

<end>.

GPIB Terminators

The only valid GPIB terminator is Eel (End or Identify) asserted with the last character sent. This is necessary because of the possibility of binary data transmission into the 7200A would make termination on a line feed alone impossible.

NOTE: The 7200A always terminates its response messages with a

line feed character with EOI asserted.

2-14

Response Syntax

RS-232-C Terminators

The COMM_RS232 command is used to define the <end> for command messages, and

separately for response messages.

The keyword El defines the <end> of command messages as a number from 1 through 127. The default value is carriage return (decimal 13). If another value is selected, it must not

used elsewhere in the command argument; otherwise, the 7200A will prematurely terminate

the command. The keyword EO defines the end of messages transmitted by the 7200A. The initial value is

CR LF (carriage return, then line feed).

For example, Arbitrary Block Program Data suitable for waveform transfers is sent as ASCII

alphanumeric characters between the range 0 through 9 and A through F. Therefore, select a number that does not have a value corresponding to the ASCII decimal values of these al-

phanumeric characters.

Response Syntax

Query commands sent to the 7200A result in information being returned. The packet of re-

turned information is called a response message. This message typically contains measure-

ment results, settings, or status information. If multiple queries are sent in the same command, the responses will be returned in one multi-response message with the individual responses separated by semicolons (";").

The computer should completely read any responses from the 7200A before sending new queries. If the computer sends a query command, starts reading the response, and issues another command before completely reading the results of the first query, the 7200A interprets this as an interrupted action, sets the query error status bit, clears the output queue,and sends the second response.

Responses conform to a general format, and with few exceptions are ASCII strings of print-

able characters. Generally, the syntax of any response is as follows:

2-15

Response Syntax

where

HEADER

Figure 2.7: Response Syntax

The syntax of a response header is the same as for a command header (see page 2-9). Prefixes are supplied when applicable. The header can be retumed in either short, long, or no header (OFF) format as specified by the command COMM_HEADER (see page 5-21). Short format produces an adequate response

for most circumstances. The long format yields the header in full

English format for increased legibility. The OFF format achieves

the fastest response time and requires little or no parsing. This part contains the information requested by the query com-

mand. It is separated from the header by one space. The argument data can be any of the types described in the Command Arguments section, p. 2-11.

one

space

Arguments

2-16

<end>

For GPIB, the <end> of a single or a multi-response message is always a line feed sent with EOI asserted.

For RS-232-C, <end> is the current setting of the EO argument

of the COMM_RS232 command which is defined as a string. The default string is a CR (carriage return) followed by a LF (line

feed). These are decimal 13 followed by decimal 10. If the <end> string is contained within the response message,

the computer may prematurely terminate the response from the 7200A. Programming <end> is provided for flexible response for-

mats but must be used with caution.

Waveform Data Syntax

If COMM_HEADER SHORT was sent before the following multi-response message:

T1 :HOR_POSlTION?; *STB?; T1 :VERT_POSrrlON?<end>

The response would be:

T1 :HPOS 1.0,1; *STB 48; VPOS 1.0<end>

Waveform Data Syntax

Waveform data is a specially formatted argument used to transfer large amounts of binary or

hexadecimal data. The WAVEFORM command uses this argument to send data to, or to

read data from the 7200A.

The 7200A supports three block data formats:

¯ Definite length arbitrary block data, ¯ Indefinite length arbitrary block data, and ¯ "OFF".

The COMM_FORMAT command (see page 5-19) is used to select the desired format.

Waveform Data transfers are used by the 7200A to send waveforms to a host controller. The

waveform query will be used in this section to describe the waveform data response format.

The WF? waveform query may optionally be followed by ALL, DESC, TEXT, DAT1, and

DAT2 to query specific parts of the waveform. If nothing follows the WF?, then ALL is as-

sumed.

Data Element Format

Each waveform point is called a data element. Using two commands, COMM_FORMAT and

COMM_ORDER, the 7200A supports several methods of forming data elements. You can

specify:

¯ the size or the width of the data element (i.e., the number of bytes), ¯ how it is encoded (i.e., binary or hexadecimal) and

¯ the arrangement of bytes for multi-byte words.

2-17

Waveform Data Syntax

Data Width

The COMM_FORMAT command is used to select the size or width of the data element; that is, the number of 8-bit data bytes used to format a data element.

NOTE: Internal to the 7200A, waveforms are kept as 16-bit signed numbers. During readout to the computer, the 7200,4 converts the intemal data words to one of."

BYTE

WORD

Data Encoding

The block data bytes are either O-bit binary or hexadecimal encoding. Use the COMM_FORMAT command to select the encoding.

BINary Binary format, the most compact, provides the fastest transfer.

HEXadecimal

8 bits, single byte per data element.

16 bits, 2 bytes per data element.

NOTE: Binary format cannot be used over RS-232-C.

Hexadecimal format ..... These numbers are indicated as AS-

CII characters between =0" through "9" and =A" through =F". Two characters represent each byte of data. The four most significant bits are represented by the first hexadecimal character, and the

four least significant bits by the second. Commas do not sepa-

rate the characters within a byte or between bytes. Therefore, to separate the values into bytes, the computer uses the data encoding specified by the COMM_FORMAT command.

A block of eight bytes, for example, is received in this format as

follows:

2-18

HEXADECIMAL

45 41 30 46 31 33 30 34 0d 0a EAOF1304<end>

where EA, OF, 13, 04 are the hexadecimal values for four successive 8-bit data bytes. (In decimal notation these values correspond to 234, 15, 19, and 04 respectively.) In this example, <end> is CR followed by LF (or 13 followed by 10 in decimal).

ASCII

Waveform Data Syntax

Byte Order When the width of the data is words, the order or sequence in which the bytes are sent can

be selected using the COMM_ORDER command: HI

The most significant byte is sent first, the least significant is sent last. This format is generally known as the Motorola format since

the most significant byte is at a lower address.

The least significant byte is sent first, the most significant is sent

last. The LO format is known as the Intel (or Zilog) format since

the least significant byte is at a lower address.

Definite length arbitrary block data

This format is used for sending blocks of previously fixed sizes. It is selected with the COMM FORMAT DEF9 comand:

#9nnnnnnnnn<DB1xDB2>,.,<DBX>

where nnnnnnnnn is a decimal integer defined by nine bytes and is used to define the number of data bytes.

<DBI>,<DB2> .....

In this format, a block of four bytes, for example, is sent or received

as follows:

#9000000004<DBI><DB2<DB3><DB4>

This format begins with a pound sign (=#") followed by a =9", then 9 bytes (which when taken together form a decimal integer equal to the number of 8-bit data bytes to follow), and the four 8-bit data bytes.

If the waveform data is the last command of the message response, the command termina-

tor follows the waveform data. (The integer following =#9" does not count this terminator); oth-

erwise, it is separated from the next command or response by a semicolon.

<DBX> are 8-bit data bytes.

Indefinite length arbitrary block data

This format is used to send blocks of unspecified length. It is selected with the

COMM_FORMAT IND0 command:

#0<DBI><DB2>...<DBX><end>

where <end> is a previously defined message terminator.

2-19

Waveform Data Syntax

The format begins with a pound sign (=#") followed by a ~0", 8-bit data bytes, and the message terminator.

Note that since the number of bytes is not known and the data is binary,it would not be possible to separate it from another command or response and therefore MUSTbe followed by

<end>. If the WF? is sent as a compound string with queries following it (i.e., T1 :WF?;T2:TRACE?),

the query error bit will be set and any queries following the WF? will be ignored. The response message will contain any responses to queries preceding WF? followed by the re-

sponse to WF?

OFF Format

Some computer languages make it difficult to check a few bytes/characters before receiving the remainder of a data block. Therefore, the 7200A has the =OFF" format which is an exten-

sion of IEEE Standard 488.2.

The OFF format is nearly Identical to #0 indefinite format, except that it supresses the #0,

keywords normally included in the response, and comma separators. It is selected with the

COMM_FORMAT OFF command. When OFF format is specified, the 7200A returns a data block having the format:

As with the #0 format above, the OFF block must be terminated with <end>.

NOTE: When writing waveforms back to the scope, the only accepted formats are #0 and #9, and the descriptor must be sent with the data.

Example: Given that Trace 1 consists of a 338 byte descriptor and 1000 bytes for data

array 1, if the block format is OFF, COMM_HEADER is OFF, and the 7200A is sent the query:

T1 :WF?<end>

the 7200A response would consist of 338 bytes for the descriptor plus 1000 bytes for the

wave array:

<338 byte DESCRIPTOR><DB339><DB340>...<DB1337><DB1338><end>

which is all data. Note, however, if the header was short or long, the prefix followed by the alias or command name, respectively, would preceed the data.

2-20

Waveform Data Syntax

To write this data back to the 7200A, precede it with the command header (’1"1 :WAVE-

FORM), its keyword (ALL), comma, and #0 pdor to transmitting the data:

T1 :WAVEFORM ALL,#0<338 byte DESCRIPTOR> <DB339>

Altematively, the #9 format may be used:

T1 :WAVEFORM ALL,#9000001338<338 byte DESCRIPTOR> <DB339> <DB340>

.... <DB1337><DB1338><end>

RS-232-C Output Format

Waveform data over GPIB can be encoded in either binary or hexadecimal (see COMM_FORMAT command). However, over RS-232-C the data encoding must be set to

HEX.

To format the appearance of the waveform data while pdnting on an RS-232-C device, use the COMM_RS232 command to specify the maximum number of characters per line. The keyword, LL, followed by a # specifies the maximum line length. After the end of each line, the designated line separator character is inserted. This character is defined by the keyword

LS in the COMM_RS232 command.

For the count in the Definite length arbitrary block data, the line separator is not counted.

Also, for block data sent to the 7200A, LS is ignored.

For example, the response to the query T1 :WAVEFORM? DAT1 can be a block of 32 bytes

of data received from the 7200A’s RS-232-C host port. It is received in definite length arbitrary block format in hexadecimal encoding (required for RS-232-C):

TI:WAVEFORM DAT1,#90000000321234567890123456<Line_Separator> DC78EF87DFOC128A<Line_Separator><end>

The =#9000000032" indicates the format ("#9") and the number of bytes sent (32 bytes cluding the LS and the <end>). Note that HEX format doubles the number of binary bytes

representing the waveform. In this example, 32 HEX bytes bytes are transferred but really represent 16 8-bit bytes of trace 1 (i.e., "1", "2" represents 12 base 16 or 18 decimal). Note also that the waveform preamble (T1 :WAVEFORM DAT1 ,#9000000032) is ALWAYS ASCII. This is always true if the data encoding is HEX or BINary. Also note that the line length (LL)

is 44 characters per line. When the <end> is reached before the LL is reached, an LS is sent before <end> is sent.

2-21

Section 3: Waveform Transfer

Waveforms can be transferred between the 7200A and an external device via GPIB, RS-232C, or MSDOS format 3-1/2" floppy disk. All types of transmission use the same format for the waveform. It is therefore possible, for example, to read a waveform out of the 7200A over GPIB, direct the output into a file on an MSDOS floppy, and then recall the waveform from

the floppy to a memory in the 7200A. Over GPIB or RS-232-C, the WAVEFORM remote command transfers a binary waveform from

an external device into the 7200A. The WAVEFORM? query transfers a binary waveform from the 7200A to an external device. The COMM_FORMAT and COMM_ORDER remote com-

mands select the data point format to be used by the 7200A when it produces waveforms in response to a WAVEFORM? query. The INSPECT?. query transfers an ASCII waveform from

the 7200A to an external device. Waveform transfer via floppy disk does not require remote programming, but may be accom-

plished with STORE and RECALL front panel operations. Remote commands STORE_SETUP, STORE, RECALL_SETUP, and RECALL may also be used to effect the store and recall operations if desired.

Waveform Template

Waveforms produced by the 7200A contain, in addition to the actual data points, further information necessary to correctly interpret the data. This information includes the real time between data points, trigger offset, vertical gain and offset, acquisition time and plugin, etc. To save space and increase the waveform transfer rate, all numerical values in the waveform are binary.

The data and associated information are organized in a specific format described by the waveform template. The template describes the size and location of each element in the waveform. It may be obtained via GPIB or RS-232-C with the TEMPLATE? query. The tem-

plate is simply an ASCII file and may be examined with any text editor. See page 3-9 for a listing of the 7200A waveform template. On each line of the template, text following a ; is

commentary.

In addition to providing a description of the waveform structure to users who wish to interpret waveforms obtained from the 7200A, the template also allows waveforms to be transferred between different LeCroy instruments and different versions of the same instrument. Waveform transferral between different LeCroy instruments may be accomplished by sending not only the waveform, but also the template according to which it was created, to the destination instrument. The destination instrument interprets the waveform data according to the associated template and translates it into its own format.

3-1

Waveform Template

As an alternative to using the template to interpret a waveform, the INSPECT? query may be used to obtain a nicely formatted and labeled ASCII representation of the waveform.

As can be seen from the template on page 3-9, a 7200A waveform consists of several distinct entities called blocks:

Waveform Descriptor Contains information necessary to correctly interpret the wave-

form data. The waveform descriptor contains two types of information:

1. Identification and description of the waveform format (name of the associated template, length of each block present in the waveform, etc.)

2. Information associated with the waveform data points (time per point, vertical gain, etc.)

User Text

Sequence Trigger Times

Wave Array 1

Wave Array 2

Each block contains distinct elements called fields. The template gives a detailed description

of the fields comprising each block. Each field is described by a line of the form:

< offset> where

offset

name

type

name:type ;comment

is the decimal offset in bytes of the field relative to the beginning of the block. (The first field in a block has an offset of zero.)

is the name of the field identifies the data format used to represent the field’s value. All numerical values

in the waveform are binary and must be interpreted according to their specified type. The possible types are described in the comments at the beginning of the waveform template on page 3-9.

This optional block may contain user documentation. This block is present only for sequence waveforms and contains

the trigger time and trigger offset for each segment of the waveform.

Contains the actual data points comprising the waveform This block is present only for dual waveforms (produced by the

EXTREMA or FFTRI functions) and contains the second data ar-

ray.

3-2

Interpreting A Waveform

For example, refer to page 3-11 of the waveform template. The value of the vertical gain is contained in the field named VERTICAL_GAIN, which is located 120 bytes from the start of the waveform descriptor block and is represented as a 32-bit IEEE format single precision floating point number.

Interpreting A Waveform

On page 3-4 is a hexadecimal/ASCII dump of an example waveform produced by the 7200A

in response to a WAVEFORM? query. The waveform descriptor block is located at the begin-

ning of the waveform and starts with the character string WAVEDESC. This is followed by the character string name of the template which describes the waveform’s organization. For the

example waveform, the template name is LECROY_I_0". To find the value of a field in the waveform descriptor, first find its offset and type in the tem-

plate. The offset specifies where to find the value in the waveform itself, and the type specifies the size of the value and how to interpret it. Then retrieve the value from the waveform and interpret it according to its type.

The byte order must also be known in order to correctly interpret numerical values. Two alter-

nate byte orders are possible:

most significant byte .. least significant byte (Motorola format) or, least significant byte .. most significant byte (Intel format).

The byte order of the waveform is specified by the COMM_ORDER field in the waveform descriptor. According to page 3-10 of the template, COMM_ORDER is a 16-bit value (type enum) located at offset 34 from the start of the waveform descriptor block. Because the waveform descriptor is the first block in the waveform, COMM_ORDER is the 16-bit value located at offset 34 from the start of the waveform. This value is 0000(16) or 0(lO). The descrip-

tion of the COMM_ORDER field in the template indicates that value 0 is the code meaning

HIFIRST. This specifies the byte ordering of all numerical values in the waveform to be

most significant byte .. least significant byte.

Once the byte order is known, any field in the waveform descriptor can be interpreted from its

offset and type specified in the template. For example, the field NOMINAL_BITS is repre-

sented as a 16-bit value (type word) located at offset 132 from the start of the waveform de-

scriptor. The 16-bit value located at offset 132 with byte ordering most significant ... least

significant is 0008(lS). Interpreting these 16 bits as a 2’s complement signed number (as

specified by type word) yields 8.

3-3

Interpreting A Waveform

OFFSET HEXADECIMAL

300000 300016 300032

300048 000064 000080

000096 000112 000128 000144 000160 000176

000192 000208 000224 000240 D00256

D00272

D00288

000304 300320 300336 300352 300368 300384

;000400

000416

000432 000448 000464 000480 000496 000512

000528

000544

57 41 56 45 44 45 53 43 O0 O0 O0 O0 O0 O0 O0 O0 4c 45 43 52 4f 59 5f 31 5f 30 O0 O0 O0 O0 O0 O0 O00l O0 O0 O0 O00l 38 O0 O0 O0 O0 O0 O0 O0 20 O0 O0 O0 36 O0 O0 O0 O0 4C 65 43 72 6f 79 20 37 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 ic 20 54 72 61 63 65 31 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 68

O0 O0 O0 64 O0 O0 O0 O0 O0 O0 O0 67 O0 O0 O0 02 O0 O0 O0 02 O0 O0 O00l 38 80 O0 O0 O0 O0 O0 O0

7f O0 80 O0 O0 08 30 89 70 5f be 5b 79 08 ae O0

O0 O0 be 5a d7 f2 8e O0 O0 O0 56 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0

O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 53 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 40 08 3d 70 a3 d7 Oa 3d 33 09 01 01 07 c5 le ea O0 O0 O0 O0 O0 O0 O0 O0 O00b O0 O0 3f 80 O0 O0 O0 11 O0 O0 3f 80 O0 O0 O0 O0 O0 O0 O0 02 O0 01 O0 O0 O0 03 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0 O0

be 5b 79 08 ae O0 O0 O0 3f Oe 77 a9 Of 40 O0 O0 be 5b cl a7 72 O0 O0 O0 ba c2 bb d4 bb cc bb dO bb c2 hb ce bb ca bb ce ]3]3 cc bb cc ba ba bb cc bb ca bc ba bb bc hb ca bc dO bc dO bb c8 cO Oa c3 30 c9 c2 cf Oe d9 b8 e3 04 ef Oe f8 3c 02 16 Ob 32 15 a2 19 70 20 4a 27 2e 29 e4 2b 5c 2f 06 2f e6 2d be 2d fa 30 76 2e 50 2f 26 2e la 2f 56 2e 34 2f 3c 2e le 2f 4c 30 4a 32 36 32 72 34 9a

bc f4 bb be bc f6 hb bc bc e8 bb cc bc d6 bb bc bc e8 bb cc bc d6 bb bc bc e8 bb cc bc d6 bc ce bd fa bc de be e8 bf O0 c4 68 c9 86 dl f8 d9 da

e4 84 ed cc f8 ea 02 2a Ob 06 13 Oc id 94 20 26 28 04 2a b4 2c 94 2d 92 31 6e 30 22 2f 02 2f 14

2f 74 2f 5c 2f 46 2e 32 2e 36 2f 44 30 3c 30 58

32 6e 31 64 34 62 33 90

ASCII

~AVEDESC ........

LECROY_I_0 ......

°°°°°°°8°°°° ....

...6 ....LeCroy 7

200 DSO ..... Trac

el .............h

¯..d .......g ....

°°°°°°°°8°°°.°°°

...... 0op o [y. o o

¯..Z ......V .....

o, oo* o°o oo, oo ¯ oo

.... o °o. oo ¯ , ° . , o

¯ ¯ ° ,o o. ¯ ..moo o,.

.... o oo °., , oo o ,.

o , oo o .o o oo o oo o . o

.......... 8.--p..

.-~3.. °o , ,°o . o ° . o

...... ? .......?.

....... o o oo o° ooo

¯ ¯ ,o ¯ o, ¯ .oo ¯ o. o.

¯ [y .....

. [oorooo ooo ooo,.

, o.o° o ..... o o . o,

... o o oo ooo o oo, oo .0°oo.oo.°o., o oo

?.w..@..

.2...p J’.),+\/..

/. -. -. 0v.P/&.../V

¯ 4/../LOJ262r4..

. ¯ ¯ * ¯ *o * o. ¯ * ¯ o o o .* ¯ oo °o . .** o. o .o ¯ ..o.o. * oho o.. oo o o oo o oo*oo .,o..

- .1nO"/./.¯

o ¯ ¯

It/\ IF. 2.61DOX

2nld4b3.

3-4

Figure 3.1: Hexadecimal/ASCII dump of a waveform

Interpreting A Waveform

Retrieving the data points of a waveform requires several steps:

1. Locate the start of the data In the waveform To locate the beginning of wave array 1 in the waveform, add up the lengths of the blocks

which precede it" waveform descriptor, user text, and sequence trigger times.

Page 3-10 of the template specifies that the length in bytes of the waveform descriptor block is contained in the field named WAVE_DESCRIPTOR, which is a 32-bit value (type long) located at offset 36 from the start of the waveform descriptor block. For the example, the 32-bit value located at offset 36 from the start of the waveform descriptor block

(which is the first block in the waveform) is (00000138)16, or (312)1o. Since the value of the WAVE_DESCRIPTOR field is (312)1o, the waveform descriptor block is (312)10 bytes long.

Page 3-10 of the template specifies that the length in bytes of the user text block is contained in the field named USER_TEXT, which is a 32-bit value located at offset

40 from the start of the waveform descriptor block. For the example waveform, the field USER_’I--P_XT in the waveform descriptor is 0. This means that the user text is not present

in this waveform. Similarly, for the example waveform the sequence trigger time array (TRIGTIME_ARRAY) is 32 bytes long.

For the example waveform, the data array (wave array 1) starts at offset 312 + 0 + 32 = 344 from the beginning ofthe waveform.

2. Determine the number of data points presenL

The total number of points in the data array is specified by the WAVE_ARRAY_COUNT field in the waveform descriptor. Page 3-11 of the template indicates that this field is a 32-bit

value located at offset (92)10. For the example waveform, WAVE_ARRAY_COUNT has the value of (00000068)16 or (104)1o.

Not every point in the data array may be valid, however. For example, if the waveform corresponds to a horizontally repositioned trace it may be missing some points off one end. The FIRST_VALID_PNT and LAST_VALID_PNT fields in the waveform descriptor give the

indices (starting from 0) of the first and last valid data points in the data array. FIRST_VALID_PNT and LAST_VALID_PNT are 32-bit values located at offsets (100)1o and

(104)1o respectively. For the example waveform, FIRST_VALID PNT is 0 and LAST_VALID_PNT is (000(X)067)16 or (103)10. Because WAVEARRAY_COUNT

(LastValid_Point - First_Valid_Point + 1), every point in the data array must be valid for

this particular waveform.

3. Determine the format or representation of each data point.

According to page 3-16 of the template, WAVE_ARRAY_I consists of an array of measurement values or data points whose data format is described by the COMM_TYPE field in the waveform descriptor block.

3-5

Interpreting A Waveform

The COMM_TYPE field specifies the size and type of data representation of each data

point. Page 3-10 of the template specifies that the COMM_’I’YPE field is a 16-bit value

(type enum), located at offset 32 within the waveform descriptor. For the example waveform, the COMM_TYPE field has the value 1. The description of the COMM_TYPE field in the template indicates that value 1 is the code meaning word. This specifies that

each point in the data array is of type word, which is a 16-bit 2’s complement signed data representation.

The first three (unscaled) points of the data array of the example waveform are (BAC2)16,

(BBD4)Is, and (BBCC)16 or (-17726)IO, (-17452)1o, and (-17460)Io.

Scale each data point value.

Further information in the waveform descriptor is used to correctly scale the vertical

magnitude of each point in the data array. The units of the vertical value are given by the VERTUNIT field of the waveform descriptor,

which is an ASCII character string located at offset 154. For the example waveform, the vertical units are V, or volts.

The vertical value Vii] of each data point i is given by the following equation: Vii] = data[i] * VER’nCAL_GAIN- VERTICAL_OFFSET

3.6

where data[i] is the ith point in the data array, and VERTICAL_GAIN and VERTICAL_OFFSET are fields in the waveform descriptor.

Page 3-11 of the template indicates that VERTICAL_GAIN and VERTICAL_OFFSET are 32-bit IEEE format floating point values located at offsets 120 and 124, respectively. For the example waveform, the VERTICAL_GAIN is (38800000)16, which corresponds to the

value (6.1 E-5)1o. The VERTICAL_OFFSET Is

Determine the horizontal coordinate of each data point.

The units of the horizontal coordinate are given by the HORUNIT field of the waveform descriptor, which is an ASCII character string located at offset 202. For the example waveform, the horizontal units are s, or seconds.

The horizontal coordinate of each data point depends on whether or not the waveform is a sequence waveform. This can be determined from the NOM-SUBARRAY_CNT field in the waveform descriptor, which specifies the nominal number of segments in the waveform.

If NOM_SUBARRAY_CNT is greater than 1, the waveform is a sequence waveform. NOM_SUB ARRAY_CNT is a 32-bit value (type long) located at offset 112. For the sample

waveform, NOM_SUBARRAY_CNT has the value 2. Thus the waveform is a sequence waveform.

Interpreting A Waveform

5.1. Non-Sequence Waveforms The horizontal coordinate T[i] of data point i is given by the following equation: T[i] = i * HORIZ_INTERVAL + HORIZ_OFFSET

where i = 0..(WAVE_ARRAY_COUNT-I)

HORIZ_INTERVAL and HORIZ_OFFSET are fields in the waveform descriptor.

For time-domain waveforms, HORIZ_OFFSET is the time in seconds from the trigger to the first data point (it may be negative) and HORIZ_INTERVAL is the time between data points, or the sampling interval. The horizontal coordinate T[i] is thus the time relative to trigger of data point i.

For frequency-domain or histogram waveforms, the above equation will yield the horizontal coordinate T[i] as absolute frequency or bin location, respectively, with units given by the HORUNIT field.

5.2. Sequence Waveforms

Sequence waveforms are composed of several consecutive segments, each of which has its own trigger time and trigger offset. The wave array block of sequence waveforms contains all the segments. The actual number of segments present is given by the SUBARRAY_COUNT field in the waveform descriptor. Note that the actual number of

segments present may be less than or equal to the nominal number given by NOM_SUBARRAY_CNT. The number of data points in each segment can be calculated

as follows: Data points per segment = WAVE_ARRAY_COUNT/NOM_SUBARRAY_CNT.

Sequence waveforms contain a sequence trigger time block which is an array of trigger

time and trigger offset for each segment. Page 3-16 of the template describes the

sequence trigger time block. The block structure contains two fields, the TRIGGER_TIME and the TRIGGER_OFFSET. In the waveform, these two fields are repeated for each segment to comprise the sequence trigger time block.

For each segment, the corresponding TRIGGER_TIME field in the sequence trigger time block contains the time in seconds between the trigger of the first segment and the trigger

of the current segment. (The time of the first trigger is given by the TRIGGER_TIME field

in the waveform descriptor). The TRIGGER_OFFSET field contains the time in seconds

from the trigger of the current segment to the first data point of the segment. The example waveform is a sequence waveform with two segments (SUBARRAY_COUNT

equals 2). The sequence trigger time block is located after the waveform descriptor and

user text blocks, and therefore starts at offset 312+ 0= 312 from the beginning of the

waveform (where 312 is the length in bytes of the waveform descriptor block and 0 is the

length in bytes of the user text block, as determined above).

3-7

Interpreting A Waveform

The trigger time block contains two consecutive repetitions of the { TRIGGER_TIME,TRIGGER_OFFSET} structure. According to the template, TRIGGER_TIME and TRIGGER_OFFSET are each 64-bit IEEE format double precision floating point values. The TRIGGER_OFFSET of the second segment is (BE5BC1A77200A0000)16, or (-2.6E-8)1o.

The HORIZ_INTERVAL field in the waveform descriptor gives the time between data points, or the sampling interval, which is the same for each segment.

The horizontal time coordinate Trel[i,seg] of data point i in segment seg relative to the trigger for that segment is given by the following equation:

Trel[i,seg] = i* HORIZ._INTERVAL+ TRIGGER_OFFSET[seg] The horizontal time coordinate Tabs[i,seg] of data point i in segment seg relative to the

first trigger is given by the following equation: Tabs[i,seg] = Trel[i,seg] + TRIGGER_TIME[seg] where seg = 0..(SUBARRAY_COUNT-1)

i = 0..(Data points per segment - 1)

3-8

Example Waveform Template

/00

000000 LECROY_I_0: TEMPLATE

; Descdptlon of the structure of waveforms produced by ; LeCroy Digital Oscilloscopes.

; A waveform consists of several logical data blocks whose formats are ; explained below. ; A complete waveform consists of the following blocks: ; the descriptor block WAVEDESC

; the text descdptor block USE~ (optional) ; the time array block (for sequence wavetorms only) ; data array block ; auxiliary or second data array block (for dual waveforms only)

; In the following explanation, every element of a block is described by a ; single line in the form

; < byte position> < variable name> : < vadable type> ; < comment> ; where ; < byte position> = position in bytes (decimal offset) of the variable,

; relative to the beginning of the block.

564 130

; < vadabla name> = name of the vadable. ;< vadabletype> = stdng

byte word long float

double enum

time_stamp

up to 16-character name

terminated with a null byte

8-bit signed data value 16-bit signed data value

32Jolt signed data value 32-bit IEEE floating point value

64Jolt IEEE floating point value enumerated value in the range 0 to N

represented as a 16-bit data value. The list of values follows immediately. consists of the following fields:

double seconds 0.00 to 59.999999) byte minutes (0 to 59) byte hours (0 to 23)

3-9

Example Waveform Template

byte days byte months

word year

1 to 31) (1 to 12) (0 to 16000)

word unused (There are 16 bytes in a time field.)

data

byte or word, as specified by the COMM_TYPE vadable in the WAVEDESC block

text

unit_definition

arbitrary length text stdng (maximum 400) 48 character null-terminated ASCII stdng

for the unit name.

WAVEDESC: BLOCK ; Explanation of the wave descriptor block WAVEDESC ; < 0> DESCRIPTOR_NAME: stdng ; the first 8 chars are always WAVEDESC < 16>

< 32>

TEMPLATE_NAME: string COMM_’I’YPE: enum

_0 byte _1 word

endenum

< 34>

COMM_ORDER: enum _0 HIRRST

_1 LORRST

endenum

3-10

; The following variables specify the block lengths of all blocks of which ; the entire waveform (as it is currently being read) is composed.

; If a block length is zero, the block Is (currently) not present.

;BLOCKS :

< 36> WAVE_DESCRIPTOR: long < 40> USER_TEXT: long

; length In bytes of block WAVEDESC ; length in bytes of block USERTEXT

;ARRAYS :

< 44> TRIGTIME_ARRAY:Iong

< 48>

WAVE_ARRAY_I: long

< 52> WAVE ARRAY_2: long

; length In bytes of TRIGTIME array ; length in bytes of 1st data array

; length in bytes of 2nd data array

; The following variables Identify the instrument

< 56> INSTRUMENT_NAME: string

< 72> INSTRUMENT_NUMBER: long

; The following variables descdbe the waveform type and the time at

; which the waveform was generated.

Example Waveform Template

< 76> TRACE_LABEL: string < 92> WAVE_ARRAY_COUNT: long

< 96> PN1S_PER_SCREBq: long

< 100> RRST_V,N.ID_PNT: long

< 104> LAST_VALID_PNT: long

< 108>

< 112>

< 116> SWEEPS_PER_ACQ: long

< 120> VERTICAL_GAIN: float < 124> VERTICAL_OFFSET: float

SUB~Y_COUNT: long

NOM_SUB.N:P, AY_CNT: long

; trace label ; actual number of points in each

; data array ; nominal number of points in each

; data array ;count of number of points to skip

; before first good point in data ; array,FIRST_VALID_POINT = 0 ; for normal waveforms.

; index of last good data point ; in data array

; for sequence waveforms,actual number ; of segments in data array

; nominal number of segments in data ; array

; NOM_SUBARRAY_CNT:= 1

; for non-sequence waveforms

; for cumulative waveforms (eg.average),

; number of sweeps which contributed to

; the waveform

; to get floating values from raw data

; VE RT~AL_GAIN * data-VERTICAL_O FFS ET

< 128> MAX_VALUE: word < 130>

< 132> NOMINAL_BITS: word

MIN_VALUE: word

; maximum allowed data value

; minimum allowed data value

; a measure of the intrinsic precision

; of the observation: ADC data is 8 bit

; averaged data is 10-12 bit, etc.

3-11

Example Waveform Template

< 134> HORIZ_INTERVAL: float

< 138>

< 146> PIXEL_OFFSET: double

< 154> < 202>

; The following variables descdbe the time at which ; the waveform was generated end the waveform type

< 250> < 266>

< 270>

HORIZ_OFFSET: double

VERTUNIT: uniLdefinltlon HORUNIT: uniLdeflnltlon

TRIGGER_TIME: time_stamp ACQ_DURATION: float

RECORD_TYPE: enum

_1 interleaved _2 histogram 3

_4 filter_coefficient _5 complex_frequency_domain

_6 7 sequence

endenum

single_sweep

trend

extrem a--envelope_display

; sampling interval for time domain ; wavoforms

; actual trigger delay (time In seconds ; from trigger to first data point)

; nominal trigger delay selected by ; user

; units of the vertical axis ; units of the horizontal axis

; time of the trigger ; duration of the acquisition (in sac)

;in multi-trigger waveforms. : (e.g. sequence or averaging)

3-12

< 272>

; The following variables descdbe the basic acquisition ; conditions used when the waveform was acquired

PROCESSING_DONE: enum

_0 no_processing _1 fir_filter

_2 Interpolated

-3 sparsed_wavaform

_4 autoscaled

_5 no_result

_6 roll_mode

_7 cumulative

endenum

Example Waveform Template

< 274> TIMEBASE: enum

_0 _1 _2 _3

_4 20_ps/div _5

_6 lO0_ps/div _7 200_ps/div _8

_9 l_ns/dlv

_10 2_ns/div _11 5_ns/div _12 _13 _14

_15 lO0_ns/div _16 200_ns/div _17

_18 l_us/div _19 2_us/div _20 5_us/div _21 lO_us/div _22 20_us/div

_23 50_us/div _24 lO0_us/div _25 200_us/div

_26 500_us/div 27 l_ms/div _28 2_ms/div _29 5_ms/div

30 lO_ms/dlv _31 20_ms/div _32 50_ms/div

_33 lO0_ms/div _34 200_ms/div _35 500_ms/div _36 l_s/div

_37 2_s/div

_38 5_s/div _39 lO_s/div _40 20_s/div

_41 50_s/div _42 lO0_s/div _43 200_s/div _44 500_s/div _45 l.._k,Vdlv

_46 2_ks/div _47 5_ks/div endenum

l_ps/div

2._ps/div

5_ps/div

lO_ps/div

50_ps/div

500_ps/div

lO_ns/div 20_ns/div 50_ns/div

500_ns/div

3-13

Example Waveform Template

< 276>

< 278> < 282>

VERT_COUPLING: enum

_0 DC_50_Ohms _1 ground ._2 DC_IMOhm

_3 ground _4 AC,_IMOhm

endenum

PROBE_ATT: float FIXED_VERT_GAIN: enum

_0 l_uV/div _1 2_uV/dlv _2 5_uV/div

_3 10_uV/div _4 20_uV/dlv

_5 50_uV/dlv _6 100_uV/div _7 200_uV/div

_8 500_uV/dlv _9 l_mV/dlv

_10 2_mV/div _11 5_mV/div

10_mV/div

_12 _13 20_mV/dlv

_14 50_mV/div _15 100_mV/dlv

_16 200_mV/div _17 500 mV/dlv _18 l_V/div

_19 2_V/div _20 5_V/dlv _21 lO_V/div

_22

20_V/div

_23 50_V/dlv

_24 f 00_V/div

_25 200_V/dlv

500 V/div

_26

_27 1 kV/div

endenum

3-14

< 284>

< 286> < 290> < 294>

BANDWIDTH_LIMIT: enum

_0 off _1 on,-60_MHz

endenum

VERTICAL_VERNIER: float ACQ VERT_OFFSET: float

WAVE_SRC_PLUGIN: enum

< 296>

< 298>

< 300>

< 302>

< 304>

_0 UNKNOWN

_1 PLUGIN_A

_2 PLUGIN_B _3

PLUGIN_C

_4 PLUGIN_D _5 PLUGIN_E _6 PLUGIN_F

endenum

WAVE_SRC_CHANNEL: enum

UNKNOWN

_1 CHANNEL_I _2 CHANNEL_2 _3

CHANNEL_3

_4 CHANNEL_4

endenum

TRIGGER_SOURCE: enum

_0 CHANNEL_I _1 CHANNEL_2

_2 CHANNEL_3 _3 CHANNEL_4 _4 _5

LINE EXT

_6 EXT/10

endenum

TRIGGER_COUPLING: (mum

AC _1 LF_REJ _2 HF_REJ

endenum

TRIGGER_SLOPE: enum

PosmvE

_1 NEGATIVE

endenum

SMART_TRIGGER: enum

_0 OFF _1 ON endenum

Example Waveform Template

< 306> < 310>

TRIGGER_LEVEL: float SWEEPS_ARRAY1: long

;for alt sync avg waveforms, ;number of sweeps which contributes to

;the number in data array 1

3-15

Example Waveform Template

< 314> SWEEPS_ARRAY2: long

;for alt sync avg waveforms, ;number of sweeps which contributed to

;the waveform In data array 1

/00 ENDBLOCK

USERTEXT: BLOCK ; Explanation of the descriptor block USERTEXT at most 400 bytes long¯

< O> DESCRIPTOR_NAME: stdng; the first 8 chars are always USERTEXT

< 16> TEXT:text

; this Is simply a list of ASCII : characters

/00

ENDBLOCK

TRIGTIME: ARRAY

; Explanation of the trigger time array (present for sequence waveforms only)

0> TRIGGER_TIME: double

; time In seconds from first trigger ; to this one

3-16

8> TRIGGER_OFFSET: double

/00 ENDARRAY

WAVE_ARRAY_ 1: ARRAY

< 0> MEASUREMENT: data

;/00 ENDARRAY

; actual trigger delay time in : seconds from this tdgger to

: first data point

; the actual format of a data Is : given in the WAVEDESC descriptor

; by variable COMM_’I’YPE

WAVE_ARRAY_2: ARRAY

Example Waveform Template

< O> MEASUREMENT: data

/00 ENDARRAY

; the actual format of a data is ; given in the WAVEDESC descriptor

; by variable COMM_TYPE

3-17

Section 4: Status Messages

This section describes the 7200A’s instrument status and event reporting functions. Although the mechanisms for requesting service differ for GPIB and RS-232-C, status and event report-

ing is identical.

GPIB Service Request

When the 7200A reports a change in its condition, it can asynchronously request service from

the GPIB controller (e.g., the 7200A can request service when processing completes). The

7200A requests service by asserting the GPIB Service Request (SRQ) management line. Once it has been enabled by setting the appropriate mask bits, the SRQ interrupts the control-

ler.

To identify the source of the SRQ, the controller serial polls the devices attached to the GPIB.

It reads the main Status Byte register (STB) of each device polled. To read the S’rB, the con-

troller addresses a device to talk and sends it a Serial Poll Enable bus command. In return, the device sends its STB. The device whose S’rB has an asserted RQS bit (seventh bit) generated the SRQ.

Once the controller determines that the 7200A generated the SRQ, it will reset the SRQ line. The 7200A will then reset its RQS bit.

RS-232-C Service Request

The RS-232-C interface does not have a line by which the 7200A can asynchronously request service from the computer. Therefore, it must query (poll) the 7200A to read the STB register.

The computer issues the status command, *S’I’B? to query the 7200A for its STB register. The seventh bit of the STB register (RQS bit for GPIB serial polling, MSS or Master Summary

Status bit for S’I’B) indicates that the 7200A requests service.

Status Byte Operation

The 720(0 continually updates its status to report the latest events, conditions, and settings. Changes are summarized by designated bits in the Status Byte register (STB). The seventh bit, RQS, is asserted whenever any other bits in the STB are reported as set and their corresponding mask bits are enabled. Also, whenever the RQS bit is set, the GPIB bus SRQ line is

automatically asserted. Typically, the controller identifies the device requesting service. It reads the other bits in the

STB register and the associated status data structure to determine the cause of, and the conditions relating to the service request. For example, whenever the sixth bit (ESB) of the STB

4-1

Status Byte

register is set, an error or synchronization event has occurred. The controller then examines the Event Status Register, a secondary status register within the status data structure, to ob-

tain details relating to that event.

Status Data Structures

In general, an asserted STB bit reflects, or summarizes, a change in a corresponding status register. It can have an encoded number which indicates a specific event or condition. Alter-

nately, it can have each of its bits report, or summarize, a change in a third status register, and so on.

Two types of status structures are the Register (individual bits) and the Queue (encoded number) models:

7200A condition or event. Altemately, each bit could act as a summary bit for an associated

status register. Using bits in one status register to indicate changes in other registers allows for a layered status description.

This layering of detail enables the controller to limit the amount of

information it receives. (Note: unless =Register Model" is specifically referenced, the term =register" refers to any byte(s) used

report a status condition or event.)

Queue Model

The following example illustrates the 7200A’s flexible status reporting capability. Each level queried yields more details about the error. Query to the required extent to prevent extraneous information from traversing the GPIB.

4-2

The Queue Model is a single register which contains an encoded

number. For example, this number may be an error code which

corresponds to an error condition. The 7200A’s queue can hold one error code. When read, the

queue will report the most recent error code, and then will clear it. When the queue is cleared (empty), the corresponding bit in the

Register Model will be cleared. Conversely, when the queue contains an error code, the corresponding bit in the Register Model

will be set.

Status Byte Register

RQS

DI07 E:

MSS O!

DI07

Status Byte Operation

= 01100000 BINARY

60 HEXADECIMAL

Standard

event status

Execution error

4.1 Example of Status Reporting

ESR = 00010000 BINARY

10 HEXADECIMAL

w w 3 ~

EXT = 00000001BINAR~

1 HEXADECIMAL

ERROR CODE OWR

(APPENDIX A)

If you sent the command A:’I’DIV 20ns to set the timebase of plug-in A to 20 nanoseconds, but the timebase did not change, you could query the STB register using the command

4-3

Status Byte

* STB?. The 7200A would return the hexadecimal number 60 (see Figure 4.3), indicating that the Event Status Register (ESR) changed.

Query another level deeper using * ESR?. The 7200A would return the hexadecimal number 10 for the value of the Event Status Register (ESR). This value means the Execution Error bit

was set. For more detail send EXR? to read the Execution Error Register. The response of 1

indicates that the Operator Warning bit is set. Progressing one more step, send OWR? to query the Operator Warning Register. Since this

"register" is a queue, the 7200A sends back an error code. Referencing this byte in Appendix A would reveal that a "data out of bounds" error occurred, since plug-in A’s timebase cannot go below 50 nanoseconds.

Event Recording

IEEE-488.2 allows two ways to record an event: Condition Registers Condition Registers are updated continually and are not cleared

when read. The 7200A has no condition registers.

Event Registers Event Registers capture changes in conditions. They are not

cleared until they are read, even if the condition which caused the event no longer exists. Each bit in an Event Register either summarizes a Condition Register, or reports a condition or event

in the 7200A.

4-4

NOTE" The *CLS command is provided to clear all Event Registers without reading them firsL (The output queue

(and its MAVsummary bit) is treated as a Condition Register. It is not cleared by the *CLS command.)

NOTE" Only changes in bits can propagate to the main status register. Therefore, the *CLS command should

be used before monitoring any register. Otherwise, if the bit was previously set, setting it again will have no effect on the main status byte.

Status Byte Operation

Event Enable Registers

Event enable registers also permit the controller to limit the amount of status information it receives. Every Register Model status register has an associated event enable register. By ma-

nipulating the associated event enable register, the controller can selectively enable or suppress (mask) the reporting of specific instrument events. Each bit in an event enable regis-

ter is =AND’ed" with its corresponding bit in the status register. For example, if the controller

sets a bit in the Event Enable register, the corresponding status event can be reported. If it is cleared, the event is masked and its reporting is disabled. In order for a service request to be

sent for an event, the corresponding bit in the event enable register, as well as all the bits above it, must be set in order to propagate the bit up to the main status byte. For example, if

bit 0 in the * STB register gets set because a trigger got done and its corresponding event enable bit (bit 0) was set in the * SRE register, then the MSS bit will be set. If bit 0 was previously 0, then because it changed to a 1, the RQS bit (bit 6) will be set in the serial poll register (along with bit 0) and the 7200A will generate an SRQ interrupt to the host computer.

If the computer performs a serial poll, the 7200A will reset bit 6 after sending its serial poll register to the host computer. However, the *S’FB register remains unaffected by this and willl still contain decimal 65 (bits 0 and 6 set). Unless the INR register is cleared by reading it

sending * CLS, future trigger completions will not generate an SRQ because the previous state was latched into the INR event register.

If a condition exists such that a bit is set in the *STB register but its corresponding bit in the ¯ SRE event enable register was not set, then the MSS bit and RQS bit will be 0 and no SRQ is generated. However, performing a serial poll will show the bit to be set in the serial poll regis-

ter. If the event enable bit in the * SRE register then gets set, the unmasked bit set in the ¯ STB register will then set the MSS bit and the RQS bit and generate a service request (SRQ)

to the host computer. In Figure 4.2, when the OWFI queue has an error code, the OWR bit is set in the EXR status

event is reported to the * ESR register. However, this event is not reported to the * STB status register because the corresponding bit in the * ESR event enable register is cleared. Since all other bits are cleared in the * ESR register, the ESB bit in the *STB register is also cleared.

Since no bits are set in the *STB, the MSS bit in the *STB is also cleared which causes the RQS bit in the serial poll register to be 0 and no SRQ is generated by the 7200A.

When the 7200A is powered on, all masks are cleared; that is, all status event reporting is disabled.

4-5

Status Byte

o o o

.arO

I [ *SRE

read by *STB

STATUS BYTE

read by sedal poll

OPERATOR WARNINGS

OWR ERROR CODE [

Queue Not Empty

Standard Event Status Enable

IIIIIIIII’EsE

0 0 0 0 0

!!lll

IIII

TTT

I Ill I’ESR

Standard Event Status

Figure 4.2 Event Enable

Execution Error

IJllllll

JJJ

& & &

J Jllol 1,1,1,1

Execution Error Enable

’EXR

*EXE

4.6

Naming Convention

The status registers follow a basic form which can be expressed as =xxR" (i.e., ESR, INR, DPR, ...). Reference to the individual bits within the status register follow the form =xxB"

(i.e., ESB, INB, DPB .... ). Reference to the mask used to enable or disable certain bits within

each register follow the form =xxE" (i.e., ESE, INE, DPE .... ). The enable register may be set

pass or block the occurrence of certain events using the general form =xxE n" where n is the value to set the enable register. For example, ESE 128 enables the PON bit in the ESR and blocks the other bits. Only registers and masks may be queried according to the general

form =xxR?’. ’ and =xxE?". The following table summarizes these general forms:

xxB xxR = Status xx Register

xxE = Status xx Enable mask xxx? = Status xxx Query

xxE n = Set Status Enable mask xxE to value n All the status bytes in the 7200A conform to either the register model or the queue model as

required by IEEE-488.2. If an event occurs which causes a bit in a register model to change (either from a 0 to 1 or a 1 to 0), that change will be propagated to any overlaying registers,

provided the enable mask is set to pass that change. For example, the bits within the ESR register are summarized by the ESB bit in the main status byte register (STB). If a bit in the

ESR register changes and the ESE mask is set to pass that change, then the ESB bit in the

main status register will be set or reset to reflect the change in the ESR. If an event occurs which causes a byte to accumulate in a queue model, then the change will

propagate to any overlaying registers. For example, the CMR is summarized by the CMB bit in the ESFL If a byte is placed in the CMR queue, the CMB bit will be set to indicate that the

queue is not empty. If the ESE mask is set to pass the change in the CMR, then the ESB bit in

the main status register will be set.

IEEE-488.2 defines certain =Common Commands", some of which are required for compliance to the standard. All IEEE-488.2 Common Commands are three letter names preceded

by an asterisk(*). For example, * RST, * IDN? ....

= Status xx Bit

4-7

Status Byte

STB Standard Definition

This section describes the function and structure of all the status registers. The main Status Byte register (STB) reflects instrument status at the time it is read. This register is usually read

when the system controller polls the 7200A. Bits in the STB summarize all the other status registers. This summary occurs by "OFring" all the reported bits in a summarized register. If the

result is TRUE, the summary bit is set. Those registers which the STB summarizes can, in turn, summarize other registers in the same way.

The STB is read with the command * STB?. Its event enable register, or mask, is set with

¯ SRE n. The mask is read with *SRE?. (Note: n is the sum of the decimal bit weights of all bits

that are true.) The * STB? query does not alter any bits in the status byte. Only the * CLS command can

clear the status byte, except for the MAV Message Available bit which depends on the state

of the Output queue. STB is shown in Figure 4.3.

4-8

[:)108

Status Byte Reglster

RQS DIG7

,.l,,v o:I01

DI06 DI05 DI04 DI03 DI01

MSS

D107

STB Standard Definition

STB

Ann done for Plug-in -~ ~ Tdg done for Plug-ln

,I I I J [ I i=kl,..

¯ Program

Running

--.~ OUTPUT QUEUE I

Commend error

3MR [ ERFIOR CODE ]. I

. VAII|A At~nt~t

Message available

Standard event status

~ ol m

Data p~ssln!

Query error

Device dependent register

II]II I r~l~l

°°~

___~ I

--] I I~1~1~1,~1~1~1

done

Processing done for traces

.~-~:~-~-~-~ WPR

Calibmtlon done for plug-ln

Max sweeps done for trace "~- ~ ~- ~-- ~- ~-- ~-- ~ MSR

Mainframe hardware fallum

=~ >, ~ -

Rug-in A hardware error

I = I’o I -o I -o I -o I -o I

I INI~I~I~I~I~I

Plug-in B hardware error

J I I :, I’o I -o I ~ I -o I -o I

EMR

EAR

EBR

Execution error

Fatal error

Internal error Operator error

t I I I I~lm_.~O[ooIEXR

Operatorwamlng

Figure 4.3: 7200A Status Byte Definition

4-9

Status Byte

Bit # Associated Status Byte 7 (MSB)

6 none RQS (service request) Bit 5 ESR 4 3

2 none Value Adapted Bit

1 0 (LSB) INn Internal State Change Bit

Bit 0:

INB - Internal State Change Bit

If the INB is set, a plug-in(s) has received a trigger(s). * For Protected Mode operation, other INB bits indicate when a plug-in(s) has bean armed.

The INB is a summary of the Internal State Register (INn). INn identifies the plug-in(s) which has received a trigger(s). Since the INn is an event register, any bits stay set until the register is read. After it is read, all the bits are cleared. Once cleared, its summary bit, INB, in the STB is also cleared.

INn’s event enable register, or mask, is INE. To set the INE use INE n, and to read it use INE?

The command used to read the INn is INFI?.

BIT #

Associated Status Byte

none Program Running

MAV Message Available bit none Reserved

DPR

Significance

Standard Event Status Bit

Data Processing Bit

Sl_onlflcance

3 2 none

for Protected Mode Operation only

none none

none

* Plug-in B armed

*Plug-in A armed Trigger done for plug-in B Trigger done for plug-in A

Bit 1: DPB - Data Processing Bit

If the DPB is set, an internal software processing event(s) has completed. The DPB bit sum-

marizes the Data Processing event Register (DPR). DPR identifies which internal software processing event(s) has completed.

Since the DPR is an Event Register, any set bits stay set until the register is read. After it is read, all the bits are cleared. Once cleared, its summary bit, DPB, in the STB is also cleared.

Before waiting for an event in the DPR register, be sure the desired DPR bits are first cleared. Otherwise, a previous event may be read.

DPR’s event enable register, or mask, is DPE. To set the DPE use DPE n, and to read it use DPE?

4-10

The command to read the DPR is DPR?.

STB Standard Definition

BIT #

9 none 8 none

7 none 6

5 4 none 3 MSR

1 WPR

Note: Bit # 4, Auto Setup Completed, is set when all the plug-ins have been automatically setup. Bit # 1, Waveform Processing Com-

pleted, is a summary bit #1at is set as soon as processing is completed. It is cleared when the WPR register is read.

MSR If the MSB bit (bit # 3 in the DPR) is set, a trace has reached its

MSR is an Event Register and gets cleared after it is read. MSR’s event enable register, or mask, is MSE. To set the MSE use MSE n, and to read it use MSE?. The command to read

the MSR is MSR?.

Associated Status Byte

none none

CAR none

maximum number of sweeps. The MSR identifies the trace(s) for which the maximum sweeps has been reached. This applies to

Summation Averaging, Histograms, Extrema, and any other routines which require a history to be accumulated.

Sianlficance

Replay Traces Done

Record Traces Done Self-test Done

Recall Done Store Done

Auto Setup Completed Maximum Sweeps Reached

Calibration Completed Waveform Processing Completed

Hardcopy Completed

BIT # Associated Status Byte Significance

7 none Max Sweeps reached for Trace 8 6

5 4 3 none 2 none Max Sweeps reached for Trace 3

0 none

none Max Sweeps reached for Trace 7 none Max Sweeps reached for Trace 6 none Max Sweeps reached for Trace 5

Max Sweeps reached for Trace 4

none Max Sweeps reached for Trace 2

Max Sweeps reached for Trace 1

4-11

Status Byte

CAR

CAR is an Event Register and gets cleared after it is read. CAR’s event enable register, or mask, is CAE. To set the CAE use CAE n, and to read it use CAE?. The command to read the

CAR is CAR?.

BIT # .~oclatad Status Byte

WPR

WPR is an Event Register that gets cleared after it is read. WPR’s event enable register, or mask, is WPE. To set the WPE use WPE n, and to read it use WPE?. The command to read

the WPR is WPR?.

If the CAB bit (bit # 2 in the DPR) is set, a plug-in(s) has pleted calibration. The CAB bit is a summary of the Calibration event register (CAR). CAR identifies which plug-in has completed

calibration.

Sl_anlflcan_,~_

none none

If the WPB bit (bit # 1 in the DPR) is set, a waveform processing event has occurred. The WPB is a summary of the Waveform Processing Register (WPR). WPR identifies the trace(s) for which

processing has completed. For history functions (Average, Histogram, Extrema,...) this event may correspond to a partial result.

That is, the waveform processing done bit is set when a trace can be displayed. For history functions, traces can be displayed before the maximum sweeps have accumulated.

Calibration Done for plug-in B Calibration Done for plug-in A

BIT # Assoclatad Stat-~ Byte

6 5

4 3

no ne none

none Waveform none Waveform none Waveform

none Waveform none none

Slonlflcance

Wavefo r m Waveform

Waveform Waveform

:~rocessing for Trace 8 done 3rocessing for Trace 7 done

3rocessing for Trace 6 done 3rocessing for Trace 5 done 3rocessing for Trace 4 done 3rocessing for Trace 3 done

~rocessing for Trace 2 done 3rocessing for Trace 1 done

Bit 2: Value Adapted Bit

The Value Adapted Bit is set to 1 if a received numerical argument was altered before being used in a computation. For example,the 7200A receives "AI:TDIV 1 lns". Since the timebase

4.12

STB Standard Definition

can only be set in multiples of 1,2, and 5, the 11 ns would get rounded to 10ns. The Value Adapted bit would be set to report that the received value was altered.

Bit 4: MAV- Message Available Bit

MAV is set if data is in the output queue. It informs the system controller that there is still data

to output. It is reset once the output queue is empty, indicating that the system controller has

read the data from the 7200A. This condition bit is not set or reset when the system controller reads STB. Also, the *CLS command does not affect this bit.

Bit 5: ESB - Event Status Bit

If the ESB is set, an error(s) or user front panel request(s) has occurred. The ESB is a mary of the Event Status Register (* ESR). IEEE-488.2 defines the * ESR to report error conditions common to most automatic test equipment. The 7200A uses most but not all of these

bits for synchronization and error reporting.

The * ESR identifies the type of error or whether a front panel request has occurred. Since the

¯ ESR is an Event Register, any set bits stay set until the register is read. After it is read, all the bits are cleared. Once cleared, its summary bit (ESB) in the STB is also cleared.

¯ ESR’s event enable register, or mask, is * ESE. To set the * ESE use * ESE n, and to read it use * ESE?. The command to read the * ESR is * ESR?..

The definition of the bits in the * ESR follow:

BIT #

7 none 6 none

3 DDR

2 QYR

1 none

URQ

Associated Status Byte

CMR

EXR

none

This event bit indicates that an off-to-on transition has occurred

in the 7200A’s power supply.

The User Request bit is set when the Remote Host port and Hardcopy ports are both set to GPIB and the front panel Hardcopy button is pressed. In this case, if the Hardcopy were to start, the 7200A would enter Talk-Only mode and disrupt the connected

Remote Host. To prevent this, the User Request bit is set allowing

the Remote Host to detect the Hardcopy request and initiate it re-

Sionlflcance

Power On User Request(Local Hardcopy Request) Command Error (syntax,unknown, cmd,...)

Execution Error (invalid parameter,...) Device Dependent Error (CAL error,...) Query Error Request Control Operation Complete

4-13

Status Byte

motely after first setting up all connected devices. Refer to Section 1 for more information.

CMR

EXR

BIT #

If the CMB (Bit # 5 in the ESR) is set, a command parsing error has occurred. The CMB bit summarizes the Command Parsing Register(CMR). The CMR identifies the most recent command

parser error. The CMR is a 16-bit queue which contains a unique encoded value. Refer to Appendix A: Command Errors, for a listing of possible command errors.

If the ~ (Bit # 4 in the ESR) is set, a command execution error(s) has occurred. The EXB bit summarizes the Command Exe-

cution register (EXR). The EXR identifies the category command execution errors. Each of four bits in the EXR corresponds to a different category of error/warning condition. A bit is

set when its category of error occurs. A 16-bit queue for each

category contains the most recent code.

Status Byte

FER IER OER

OWR

Typical errors include:

prefix illegal too many parameters

plug-in not present data block error data block descriptor error data processing error units do not match

Slaniflcance

Fatal Error

Internal Error Operator Error Operator Warning

4-]4

DDR

If the DDB (Bit # 3 in the ESR) is set, a device specific error(s) has occurred. The DDB bit summarizes the Device Dependent Register (DDR). The DDR specifies the origin of the failure (plugin(s) and/or mainframe). Each bit in the DDR is a summary mes-

sage bit for a status register corresponding to each plug-in and for the mainframe. The DDR is an event register that gets cleared

when read.

STB Standard Definition

DDR’s event enable register, or mask, is DDE. To set the DDE use DDE n, and to read it use DDE?. The command to read the DDR is DDR?.

BIT #

2 EBR Plug-in B error

0 EMR Mainframe error

ExRBits

The x in ExR represents M,and A and B for mainframe and plug-ins, respectively.

ExR’s event enable register, or mask, is ExE. To set the ExE use ExE n, and to read it use ExE?. The command to read the ExR is ExR?.

Typical device specific errors include channel overloads, hardware failures, and self-test fail-

ures. This is an event register and gets cleared after it is read. Bit assignments for ExR, for the plugin:

BIT # Associated Status Byte Slanlflcance

5 4 3 2

1 none

Associated Status Byte Si_onificance

EAR Plug-in A error

These bits indicate the type of device specific error. Each plug-in and mainframe bit in the DDR summarizes an ExR register. The

system controller can read these registers to determine the type of error which occurred in the plug-in or mainframe. The definition of the bits in the ExR for all the plug-ins are the same.

none Calibration Failed none External overload none Channel 4 overload none Channel 3 overload

Channel 2 overload

none

Channel 1 overload

Bit assignments for EMP~

BIT #

7 none reserved 6

5 4 3 none

0 none

Associated Status Byte Si_oniflcance

none reserved none System clock failure none I/O failure

Hard disk failure

none none

Floppy failure Display failure

Internal comm. failure

4-15

Status Byte

QYR

RQC

OPC

If the QYB (Bit #2 of ESR) is set, a query error(s) has occurred.

The QYB bit summarizes the Query Error Register (QYR). QYR identifies the most recent query error. The QYR is a 16-bit queue

which contains a unique encoded value. The value indicates query errors. Typical errors include:

Query CHANNEL ALL when both channels are not equal. Buffer deadlock: input and output buffers full. Unterminated: controller reads before sending a complete

query message.

Interrupted: controller sends new command before reading last query.

Query after indefinite response.

The Request Control bit in the ESR is never set because the 7200A does not have controller capability.

To conform to IEEE-488.2, the 7200A will set the OPC bit (Bit # in the ESR) in response to an *OPC command. The query

* OPC? will return a

This bit is set upon completion of any operation. At any one time, several operations can be performed and be in various states of

completion. To correctly determine which operation completed, monitor the Internal State Register (INR) and the Data Processing

"1".

Bit 6: RQS - Request Service Bit

The RQS bit is a summary bit for the other bits in the STB byte. For GPIB, an SRQ interrupt is

generated when the RQS bit is set if the corresponding bit in the SRE mask is set. For RS-232-C, the computer must poll the STB register and read the FIQS bit to determine the

most recent status.

Bit 7: Program Running Bit

This bit is set when an ICL Program (See Section 7) is executing and is reset when the ICL Program has completed execution.

NOTE" When an ICL Program is running, remote commands are locked out. Therefore, bit 7 of the main status byte should always be checked (using a serial poll) before sending remote commands

ensure proper remote operation.

4.16

Mainframe Remote Comnmnds

Section 5: Mainframe Remote Commands

Acquisition Commands

"TRG .................... 5-179

*TST? .................... 5-180

AFWI_ACQUISmON ARM .......... 5-7

AUTOSETUP ASET ............ 5-9

REFERENCE_CLOCK RCLK ........ 5-131

STOP ....................

TIMEBASE._LOCK TBLK ..........

TRIG_ENABLE TREN ............ 5-150

TRIG_LOCK TRLK ............. 5-151

TRIG_MODE TI:~ID ............. 5-152

WAIT ..................... 5.156

ALL_STATUS? ALST? ............

AF~I_ACQUISmON AFWl .......... 5-7

AUTO_CAL ACAL .............. 5-8

AUTO_SETUP ASET ............ 5-9

AXIS_LABEL AX]L .............. 5-10

BUZZER BUZZ ............... 5.11

CAE .....................

Calibration and Test Commands

*CAL? .................... 5-168

*FIST ..................... 5-176

AUTO_CAL ACAL .............. 5-8

CAR .....................

CENT .................... 5-14

CENTER_MAX CMAX ............ 5-16

CLEAR_DISPLAY CLRD .......... 5-17

CLEAR_MEMORIES CLRM ......... 5-18

CMR ..................... 5-19

COLOR COLR ............... 5-20

COMM_FORMAT CFMF ..........

COMM_HEADER CHDR .......... 5-24

COMM_ORDER CORD ........... 5-25

COMM_RS232 CORS ........... 5-26

COMM_SCSI COSC ............ 5-28

Communication Commands

*WAI ..................... 5-181

CENT ....................

COMM_FORMAT CFMT ..........

COMM_HEADER CHDR .......... 5-24

COMM_ORDER CORD ........... 5-25

COMM_RS232 CORS ........... 5-26

5-137 5-143

5-6

5.12

5-13

5-22

5-14

5-22

COMM_SCSI COSC ............ 5-28

DATA_DEST DDST ............. 5.36

GPIB_ADDRESS GPAD ........... 5-66

LOCAL LOC ................. 5-84

LOCKOUT LLOK .............. 5-85

REM CTRL RCTL .............. 5-133

REMOTE REM ................ 5-132

SCSI_ID? SCID? ............... 5-135

TFIANSFER_RLE TRR ...........

COPY_RLE COPY .............

CURSOR LOCK CRLK ........... 5--30

Cursor Meaeursmant Commands

CURSORLOCK CRLK ........... 5-30

CURSOR_MEASURE CI:~IS ........ 5-31

CURSOR_SET CRST ............ 5-32

CURSOR_VALUE? CRVA? ......... 5-34

PARAMETER_ADD PAAD .......... 5-92

PARAMETER_AVG PAAV .......... 5-103

PARAMETER_CLR PACL .......... 5-104

PARAMETER_DEL PADL .......... 5-105

PARAMETER_VALUE? PAVA ........

PER_CURSOR_SET PECS ......... 5-108

PER_CURSOR_VALUE PECV ........ 5-110

XY_CURSOR_ORIGIN XYCO ........ 5-162

XY_CURSOR_SET XYCS .......... 5-163

XY_C URSOR_VALUE XYCV ........ 5-165

CURSOR_MEASURE CF~S ........ ,5-31

CURSOR_SET CRST ............ 5-32

CURSOR_VALUE? CRVA? ......... 5-34

DATA_DEST DDST ............. 5-36

DATE ..................... 5-37

DDE ..................... 5-38

DDR ..................... 5-39

DEFINE DEF ................. 5-40

DERNE_REPLAY DEFR ........... 5-48

DELETE_RLE DELF ............. 5-49

DIRECTORY_LIST DIR ........... 5-50

Display Commands

AXIS_LABEL AX]L .............. 5-10

BUZZER BUZZ ............... 5-11

COLOR COLR ................ 5-20

DISPLAY DISP ................ 5-51

5-148 5-29

5-106

5-1

Mainframe Remote Commands

Mainframe Remote Commands (continued)

DISPLAY_UPDATE DISU .......... 5-52

DOT_JOIN DTJN .............. 5-53

GRID_STYLE GRDS ............

HIST_ORIENT HISO ............

HOR_MAGNIFY HMAG ...........

HOR_POSITION HPOS ........... 5-77

INTENSITY INTS ..............

MULTI_ZOOM MZOM ...........

MULTI_ZOOM_SETUP MZSU .......

PERSIST PERS ............... 5-112

PERSIST_SETUP PESU .......... 5-113

RECALLPANELS RCPN .......... 5-127

SELECT SEL ................ 5-136

STORE_PANELS STPN ...........

TRACE TRA ................. 5-144

TRACE_ANOT TRAA ............

VERT_IVlAGNIFY VlVlAG ........... 5-154

VERT_POSITION VPOS ..........

XY_A,SSIG N XYAS .............

XY_DISPLAY XYDS ............. 5-167

DISPLAY DISP ............... 5-51

DISPLAY_UPDATE DISU ..........

DOT_JOIN DTJN ..............

DPE ..................... 5-54

DPR .....................

EAE, EBE ..................

EAR?, EBR? .................

EME ..................... 5-59

EMR ..................... 5-60

EXE .....................

EXR ..................... 5-62

FER? ....................

FIND_CTR_RANGE FCR ..........

FORMA’rr_FLOPPY FFLP .........

GPIB_ADDRESS GPAD ...........

GRID ..................... 5-67

GRID_STYLE GRDS ............ 5-68

Hardcopy Commands

HARDCOPY HCPY ............. 5-69

HARDCOPY_SETUP HCSU ........ 5-70

HARDCOPY_TRANS HCTR ......... 5-74

HARDCOPY HCPY .............

HARDCOPY_SETUP HCSU ........

5-68 5-75 5-76

5-83 5-88 5-89

5-139 5-145

5-155 5-161

5-52 5-53

5-55 5-57

5-58

5-61 5-63

5-64 5-65 5-66

5-69 5-70

HARDCOPY_TRANS HCTR ........

HIST_ORIENT HISO ............

Histogram Paramaters ........... 5-100

HOR_MAGNIFY HMAG ..........

HOR_POSmON ..............

Identification/Data Commands

*IDN? .................... 5-172

"OPT? ...................

DATE .................... 5-37

PRW ON STATE PWRO .......... 5-124

UPTIME UPTI ................ 5-153

IER? .....................

INE ..................... 5-79

INR? ....................

INSPECT? ................. 5-81

INTENSITY ................. 5-83

LOCAL ...................

LOCKOUT .................

MSE ....................

MSR ....................

MULTI_ZOOM MZOM ...........

MULTI_ZOOM_SETUP MZSU .......

OER? .................... 5-90

OWR? .................... 5-91

PARAMETER_ADD PAAD .........

PARAMETER_AVG PAAV ..........

PARAMETER CLR PACL ......... 5-104

PARAMETER_DEL PADL ..........

PARAMETER_VALUE? PAVA? .......

PER CURSOR_SET PECS .........

PER_CURSOR VALUE? PECV? ......

PERSIST PERS ............... 5-112

PERSIST_SETUP PESU .......... 5-113

PROG_ARG PRAR ............. 5-114

PROG_CLEAR PRCL ............

PROG_COMPILE PRCO ..........

PROG_LIST PRLI ..............

PROG_MODE PRMO ...........

PROG_RECALL PRRC ...........

PROG_SETUP PRSU ............

PROG_STORE PRST ............

5-74 5-75

5-76 5-77

5-175

5-78

5-80

5-84

5.85 5-86 587 588

589

5-92 5-103

5-105 5-106

5-108 5-110

5-115 5-116 5-117

5-118 5-119 5-120 5-122

5-2

Mainframe Remote Commands

Mainframe Remote Commands (continued)

Program Commands

*LRN? ....................

PROG_ARG PRAR .............

PROG_CLEAR PRCL ............

PROG_COM PILE PRCO ..........

PROG_LIST PFLI ..............

PROG_MODE PRMO ............

PROG_RECALL PRRC ........... 5-119

PROG_SETUP PRSU ............

PROG_STORE PRST ............

PROTECT_MODE PF~ID ($I Option only) PRW_ON_STATE PWRO ($I Option only) 5-124

QYR? .................... 5-125

RECALL REC ................

RECALL_PANELS ROPN ..........

RECALL_SETUP RCST ...........

RECORD_TRACES RECT .........

REFERENCE_CLOCK RCLK ........

REM_CTRL RCTL ..............

REMOTE REM ...............

REPLAY_TRACES REPT ..........

SCSI_ID? SCID? ..............

SELECT SEL ................

Status Register Commands

*CLS ....................

* ESE ....................

*ESR? ....................

*OPC .................... 5-174

*SRE ....................

*STB? ....................

ALL_STATUS? ALS’T’? ...........

CAE .....................

CAR?. ....................

CMR? ....................

DDE ..................... 5-38

DDR? .................... 5-39

DPE .....................

DPR? ....................

EAE, EBE ..................

EAR?, EBR? .................

EME .....................

EMR? ....................

EXE .....................

5-173 5-114 5-115 5-116 5-117 5-118

5-120 5-122 5-123

5.126

5.127

5.128

5.130 5-131

5-133 5-132 5-134

5-135 5-136

5-169 5-170 5-171

5-177 5-178 5-6

5-12

5.13

5.19

5-54

5.55 5-57

5-58

5-59

5-60 5-61

EXR? .................... 5-62

FER? ..................... 5.-63

IER? .....................

INE ...................... 5-79

INR?. .....................

MSE .....................

MSR? ....................

OER? .................... 5-90

OWR? .................... 5-91

QYR? ....................

WPE .....................

WPR? .................... 5.160

STOP .................... 5-137

STORE STO .................

STORE_PANELS STPN ...........

STORE_SETUP STST ............

TEMPLATE? TMPL? ............ 5.142

TIMEBASE_LOCK TBLK .......... 5.143

Trace Equation Setup

CENTER_MAX CMAX ............ 5-16

CLEAR_DISPLAY CLRD ........... 5-17

DEFINE DEF .................

DEFINE_REPLAY DEFR ...........

RND_CTR_RANGE FCR ..........

TRACE_LABEL TRLB ............ 5-147

TRACE TRA .................

TRACE_ANAT TRAA ............. 5.145

TRACE_LABEL TRLB ............

TRANSFER_FILE TRR ........... 5-148

TRIG_ENABLE TREN ($1 Option only)... 5-150

TRIG_LOCK TRLK ..............

TRIG_MODE TFWlD .............

UPTIME UPTI ................

VERT MAGNIFY VMAG ...........

VERT_POSITION VPOS ........... 5-155

WAIT ..................... 5.156

Waveform Storage

CLEAR_MEMORIES CLI:~ .........

COPY_RLE COPY .............

DELETE_FILE DELF ............. 549

DIRECTORY_LIST DIR ........... 5-50

FOF~IAT_FLOPPY FFLP .......... 5-65

5-78 5-80

5-86

5-87

5-125

5.159

5-138

5-139

5.140

5-40 5-48

5-.64

5.144 5-147

5-151

5.152

5.153 5-154

5-18

5.29

5-3

Mainframe Remote Commands

PROTECT_MODE PFWlD ..........

RECALL REC ................

RECALL_SETUP RCST ........... 5-128

RECORD_TRACES RECT ......... 5-130

REPLAY_TRACES PEP1" .......... 5-134

STORE STO ................

STORE_SETUP STST ........... 5-140

Waveform Tran=fer Commands

INSPECT INSP ............... 5-81

TEMPLATE TMPL? .............

WAVEFOF~I WF ..............

WAVEFOFWI? WF? ............. 5-158

WAVEFO FIM WF ..............

WAVEFOF~? WF? .............

WPE .....................

WPR? .................... 5-160

XY ASSIGN XYAS ............. 5-161

XY_CURSOR_ORIGIN XYCO ....... 5-162

XY_CURSOR_SET XYCS .......... 5-163

XY_C URSOFLVALUE? XYCV? ...... 5-165

XY_DISPLAY XYDS .............

5-123 5-126

5-138

5-142 5-157

5-157 5-158 5-159

5-167

(continued)

Mainframe Remote Commands

Organization

Each command description begins a new page. A command’s name (header) is printed long and short form near the top of the page. Although the long form is used in the descrip-

tion, the short form can be used instead. Below the header are up to eight sections which de-

scribe it:

Purpose: explains a command’s use Command: contains a command’s syntax Query: contains the query syntax

Response: contains the syntax of the response to a query Argument:

Example: includes the command being used

Note: reports additional considerations See Also: cites other relevant commands

defines a choice(s)

Command Execution

Execution of program messages depends on the instrument status. As a rule, commands and queries can be executed in either Local or Remote mode.

Before attempting to execute a command or query, the parser scans it to verify its correctness and that sufficient information is given to perform a requested action.

5-5

Mainframe Remote Commands

ALL_STATUS?

Purpose:

Query. Response: Argument:

Examples:

See Also:

The query commands for each of these status registers.

ALST?

Reads the contents of all status registers. After event registers are read,

they are cleared. For an interpretation of each register’s contents, refer to the appropriate status register description.

The ALST? query is useful for a complete overview of the instrument’s state. ALL_STATUS?

ALL_STATUS register,value,register,value ....

ALL_STATUS? Read the contents of all status registers. ALL_STATUS * S’rB,0,* ESR,0,CMR,0,EXR,0,FER,0,1ER,0,OER,0,

OWR,0,DDR, O,EBR, O, EAR,0, EM R,0,QYR,O, DPR,0,MSR,0,CAR,0,WPR,0,1NR,0 < end>

5-6

Mainframe Remote Commands

ARM_ACQUISITION

Purpose:

Command: Note: See Also:

Enables the signal acquisition process by changing the acquisition state

from TRIGGERED to READY. ARM_ACQUISITION

This command works identically as the *TRG command. *TI:~

ARM

5-7

Mainframe Remote Commands

AUTO_CAI,

Purpose: Command: Query:.

Response: Argument:

Examples:

Note:

ACAIJ

To enable or disable automatic calibration of 7200A plugins.

AUTO_CAL state AUTO CAL? AUTO_CAL state state ON

OFF

ACAL ON

ACAL?

ACAL ON Automatic caUbration is always enabled when the 7200A is powered on or

reset.

I/Vhen controlling the 7200A from remote, it is recommended that automat-

ic calibrations are disabled, since they will occur asynchronously and can take several seconds per plug-in to complete. However, if you do disable

it, periodic calibrations should be performed via the *CAL ? command.

Causes the 7200A to periodically perform an automatic recalibration of the plugins.

Disables automatic recalibration of plugins. enables automatic calibration.

Queries whether automatic calibration is enabled or disabled.

Reports than automatic calibration is enabled.

See Also:

5-8

* CAL?

Mainframe Remote Commands

AUTO_SETUP

Purpose:

Command: Notes:

Sets up acquisition parameters automatically. The command attempts to

display the input signal(s) by adjusting the vertical, timebase, and trigger parameters. If input signals are available and more than one channel is be-

ing displayed, the signals will be scaled vertically and the timebase will be

chosen to best display Channel 1. If only one input channel is turned on, the timebase will be adjusted for that channel.

AUTO_SETUP When locked timebase is selected, the Umebase controls will be set up

based on the leftmost plugin’s control settings.

ASET

5-9

Mainframe Remote Commands

AXIS_LABEL

Purpose:

Command: Query:. Response:

Arguments:

Example:

See Also:

AXIL ON AXIL?

AXIL

SELECT

AXIL

This command enable/disables the display of the end point values for the active trace on both the horizontal and vertical axes. If enabled, the values

are printed when the grid is either single or dual.

AXIS_LABEL state

AXIS_LABEL?

AXIS_LABEL state state ON

OFF

displays the values corresponding to the active trace at the end of each axis.

takes the values of the axes off the display. tells the 7200A to display the axis values. asks if the axis lables are on or off.

response indicates axis labels are not displayed.

5-10

Mainframe Remote Commands

BUZZER BUZZ

Purpose:

Command:

Briefly sounds the buzzer.

BUZZER

5-11

Mainframe Remote Commands

Purpose:

Command: Query:. Response: Argument:

Examples:

Sets the Calibration Enable register (CAE). The CAE register determines which events in the Calibration status Register (CAR) are reported. CAR identifies which plug-in has completed calibration. Any reported CAR event

sets the CAB summary message bit (bit # 2) of the Data Processing Register (DPR) and propagates to the main Status Byte (STB).

CAE mask

CAE? CAE mask

mask

CAE 3

CAE?

CAE 3

When expressed in binary, this number (between 0 and 63) represents the bits of the CAR that can be reported:

Bit #

enables the events represented by the lower two bits of this event register (i.e., calibration done for plug-ins A and B). bit 1 (decimal 2), and bit 0 (decimal 1). Summing the decimal values yields 3.

Read the contents of the CAE. Response indicates the contents as 3, i.e., the lower two enable bits are set.

Associated Sianificarl(;e Calibration Done for plug-in B Calibration Done for plug-in A

See Also:

5.12

CAR?.

CAR?

Mainframe Remote Commands

Purpose:

Query:. Response:

Argument

Examples:

See Also:

Reads and then clears the Calibration event Register (CAR) which identifies

which plug-in has completed calibration. Clearing the CAR register also clears the CAB summary message bit

(bit # 2) of the Data Processing Register (DPR) and the effect could propa-

gate to the main Status Byte (STB). CAR? CAR value

value

CAR?

CAR 2 ALL_STATUS, CAE, * STB?

When expressed in binary, this number (between 0 and 63) represents the bits of the CAR:

Bit # 1

Read and clear the CAR register contents. Response indicates that calibration done for plug-in B.

Associated Significance Calibration Done for plug-in B

Calibration Done for plug-in A

5-13

Mainframe Remote Commands

CENT

Purpose:

Command: Query. Response: Arguments:

Reads and writes the centronics port for synchronization and control of external events. The command and query can be used in a variety of ways such as limit testing and external triggering. Since the 8 outputs provide

standard -I-n_ levels, they can be used to initiate some external action while the 7200A is left monitoring (babysitting) an input signal.

CENT value

CENT?

CENT value value The actual data to be written to or read from the centronics port.

When writing, value may be specified in decimal, hexadecimal

(# H), octal (# Q), or binary (#

When writing the centronics port, the actual pins which correspond to the data value are as follows:

Data Bit

D1 3

D2 D3

D4 D5 D6

137

DB25-D .Din

2 2 4

5 5 6 6 7 7 8 8 9 9

36-Din bali lock

3 4

5-14

CENT (continued)

When reading the centronics port using CENT?., the data value returned is bit-encoded as follows:

Mainframe Remote Commands

Examples:

Note:

Data Bit DB25-D pin DO 10 10 ACKNOWLEDGE

D1 11 11 BUSY

D3 13 13 SELECT

D4 15 32 ERROR

CENT 8 Sets pin 5 high on the DB25-D Centronics parallel

CENT # Bl1001010 Sets pins 3,5,8 and 9 high and pins 2,4,6 and 7 are

CENT?

CENT21 Response indicates that pins 10,12, and 15 are pulled

The CENT command is not intended to drive a printer since the normal data transfer sequence is not carried out.

Data written to the DB25-D connector remains latched on pins 2 through 9 until another byte overwrites it.

12 12 PAPER OUT

output connector; pins 2,3,4,6 through 9 are set low.

set low on the DB25-D connector.

high and pins 11 and 13 are pulled low on the DB25-D

connector (decimal 21 = 00010101 in binary)

36-pin bail lock

Centronics bail lock Signal Name

All voltages appearing on pins 2 through 9 are based on TTL levels and are driven by a continuously enabled bus transceiver. When interfacing exter-

nal devices, please refer to the appropriate data sheet to avoid overloading. The CENT?. query allows external hardware signals to be read remotely. If

there is no connection to these input pins, they are considered to be floating and the query response may return random data. If only some input pins are used, then the appropriate data bits should be isolated from the query response.

5-15

Mainframe Remote Commands

CENTER MAX

Purpose:

Command:

Arguments: prefix Examples: T3:CMAX

See Also:

Automatically moves the center of a histogram to the mode of the currently accumilated histogram.

prefix:CENTER_MAX

FIN D_CTR_RANGE

CMAX

The prefix is limited to traces T1, "I"2 .....

Automatically moves the center of the histogram defined in trace

3 to the mode of the current histogram.

5-16

Mainframe Remote Commands

CLEAR_DISPLAY

Purpose:

Command: Note:

See Also:

Reset the data associated with the history function(s) as applicable (e.g., Average, Extrema, etc.) and also clears the persistence display.

CLEAR_DISPLAY When this command is received, all data generated by the history functions

(Average, Extrema, Histogram, and Trend) is set to zero and the count(s) of the number of sweeps is set to zero. Also, if persistence is on, the display is cleared and its sweep count is reset to zero. If no history function is being used and persistence is not on, this command has no effect.

DEFINE, DEFINE_REPLAY, PERSIST

CLRD

5-17

Mainframe Remote Commands

CLEAR_MEMORIES

Purpose:

Command:

Clears the eight memories M1 ....

Clear_Memories

CLRM

M8 and the record traces buffer.

5-18

CMR?

Mainframe Remote Commands

Purpose:

Query. Response:

Argument:

Reads and then clears the contents of the Command error Register (CMR).

The CMR register identifies the most recent command parser error. A com-

mand error is reported whenever the 7200A detects a syntax error or is un-

able to parse the command or query. The CMR is a single-value queue which contains a unique encoded value.

The value corresponds to the most recent command error. An encoded value is assigned to every error message that can appear on the screen.

Values are also assigned to remote specific errors. A listing of all encoded values with their meanings is found in Appendix A.

Clearing the CMR register also clears the CMB summary message bit (bit # 5) of the standard Event Status Register (ESR) and the effect could

propagate to the main Status Byte (STB).

CMR?

CM R value

value

Corresponds to an error. Typical errors include: Header error

String error Keyword error Number error Suffix error Prefix illegal

Too many parameters

EOI detected during definite length data block

transfer

Example:

See Also:

CMR?

CMR 453 ALST?, * CLS, * S’T’B?

Read and clear the CMR. Response indicates unknown remote command.

5-19

Mainframe Remote Commands

COLOR

Purpose:

Command: Query:. Response: Argument:

COLR

Determines the color assignments for the different display entities as well

as how many color should be used to display the traces.

COLOR keyword, value [,keyword, value] COLOR?

COLOR keyword, value, keyword, value, keyword, value

An argument consists of a keyword followed by its value. Any number of arguments, in any order may be used.

Kevword

TRACES Selects how many different colors should be used to

SCHEME

Meanina: Value

display the traces. Choices are 1 (all traces the same color), 2 (the active trace one color, all other traces a second

color), and 8 (each trace is a different color). Selects the color scheme to use. The color scheme is a

file (in the panel setup directory with a ".COL" extension for color systems and =.MOW’ for monochrome systems)

that contains a list of the color assignments for each possible display entity. The file DEFAULT.COL contains a description of each of the fields.

Example:

5-~0

CONTRAST Selects the difference in intensity of the dark, medium,

and bright colors of each hue. Bright colors are used for highlighting entries which you can change in setup screens and for acquired points in expanded waveforms. The contrast is a percentage ranging from 5, in which there is very little difference in intensities, to 95, where all but the bright colors are nearly black.

COLR

COLR?

SCHEME, DEFAULT, TRACES, 8

Sets the color scheme according to the file =DEFAULT" and specifies that a different color should be used for each trace.

requests the current color settings

Mainframe Remote Commands

COLOR (continued)

COLR SCHEME, PRIMARY, TRACES, 2, CONTRAST, 30

Note:

See Also:

For the 7200A with the color option, the ICL program, COLOR, can be used to generate your own customized color scheme.

INTENSITY

COLR

reports that the color scheme is currently determined by

the file "PRIMARY" and that only the active trace is a different color, and the contrast is 30.

5-21

Mainframe Remote Commands

COMM_FORMAT CFMT

Purpose:

Command: Query:.

Response: Arguments:

Determines the format which the 7200A will use to send waveform data. The available options set: (1) the data block format, (2) the data word size,

and (3) the data encoding to be modified from the default settings

COMMFORMAT format, data_width, encoding COMM_FORMAT?

COMM_FOFWlAT format, data_width, encoding format, choice of data block format:

DEF9

INDO indefinite length, has the block format:

OFF has the block format:

definite length, has the block format : #9nnnnnnnnn< DBI> < DB2> ...< DBn>

#0< DBI> < DB2> ...< DBn> < end>

< DBI> < DB2> ...< DBn> < end> where nnnnnnnnn is a decimal integer defined by nine bytes

and indicates the number of data bytes. < DBn> represents a data byte and < end> is the message terminator.

5-22

datajidth, choice of:

BYTE 1 byte

WORD 2 bytes

encoding, choice of:

BINary HEXadecimal

the most compact, provides the fastest transfer two ASCII characters, 0" through 9" and

A through F, represent the contents of each data byte. The first character represents the four most significant bits.

Mainframe Remote Commands

COMM_FORMAT (continued) CFMT

Examples:

Note:

See Also:

CFMT DEF9,WORD,BIN

CFMT?

CFMT IND0,BYTE, HEX

RS-232-C requires HEX encoding, GPIB can use either.

Waveform data points result from 8-bit ADCs so that a data_width of BYTE can fully describe each point. Selecting a data_width of WORD simply

places the BYTE in the upper half of a 16-bit WORD and clears the lower half.

The format set by this command only affects the WAVEFORM command. The format OFF is an extension to the IEEE-488.2 standard and is provided

for special applications where the absolute minimum of data transfer may be important. It suppresses any keywords normally included in the response, and comma separators.

WAVEFORM

Sets the format to # 9 definite length block,

with 16 bit data words in binary encoding.

Requests the current format settings Reports the data block is indefinite length

format, with 8 bit data words in hexadecimal encoding.

5-2,3

Mainframe Remote Commands

COMM_HEADER CI-IDR

Purpose:

Command: Query:. Response: Arguments:

Examples:

Specifies which type of ASCII header, if any, should be sent with a response to a query. The response header can have three forms:

LONG: SHORT: OFF:

COMM_HEADER arg COMM_HEADER?

COMM_HEADER arg arg, choice of :

CHDR SHORT Tells the 7200A to start responses with the

CHDR? Requests the current header type. COMM_HEADER LONG Reports the current header type as LONG.

If the 7200A received T1 :VPOS?, it would respond with:

Full command name followed by its argument(s), Abbreviation of the command followed by its argument(s), Just the argument(s) with no command name.

OFF (no header), SHORT (abbreviated command name),

LONG (full command name)

abbreviated command names.

Note:

.$-24

T1 :VERT POSITION 1.0 T1 :VPOS 1.0

1.0

COMM_HEADER only affects the response header. Long or short forms can always be used for sending commands to the 7200A. Arguments are

not affected.

if CHDR LONG if CHDR SHORT if CHDR OFF

Mainframe Remote Commands

COMM_ORDER

Purpose:

Command: Query:. Response:

Argument: Examples:

Note: See Also:

Specifies the order of bytes for two byte data words. High byte (most significant byte) first is generally known as Motorola format. Low byte (least

significant) first is called Intel format and is also used by an IBM PC or compatible.

COMM_ORDER arg COMM_ORDER?

COMM_ORDER arg arg choice of HI or LO

CORD LO Causes the least significant byte of a two byte data word to be

CORD?

CORD HI COMM_ORDER only applies to block data in the WAVEFORM command. WAVEFOF~I

CORD

sent first. (This is how it should be set when reading into an IBM PC or compatible.)

Requests the current order in which bytes are sent. Indicates Motorola format

5-25

Mainframe Remote Commands

COMM_RS232

Purpose: Command: Query:.

Response: Arguments:

Defines the RS-232-C message exchange protocol. COMM_RS232 keyword,value, keyword,value,...,keyword,value

COMM_RS2327

COMM_RS232 keyword,value,keyword,value keyword

El End_In terminates command messages:

EO End_out terminates response messages:

LS Line_separator: CR, LF, CRLF, or OFF

LL Une_length, for LS not OFF:

EC Echo determines if received characters are sent back OFF

Meaning: values

1 through 127

Alphanumeric string of no more than two

characters

40 through 1024

CORS

Initially selected valu0

\An

OFF

1024

Examples:

5-26

Baud Rate: 19200, 9600, 4800, 2400, 2000, 1800, 1200, 1050, 600,

300,200, 150, and 110 SB Stop Bits: 1 or 2 PR Parity: NONE, ODD, or EVEN

Data Bits: 5, 6, 7, or 8

Handshake method: HARDWlRE, XON-XOFF

An argument consists of a keyword followed by its value. Any number of arguments may be used in any order to change individual settings.

CORS EC,OFF,LL,80 Selects echo off and a line length of 80.

Mainframe Remote Commands

COMM_RS232 (continued)

CORS? Query, which has no parameters, requests the state CORS BR,9600,SB,1 ,PR, NONE,DB,8,HS,XON-XOFF,EI,13,EO,~ r\ n",

LL,1024,LS,OFF, EC,OFF

Note:

The keywords have the following meanings:

Echo

(EC)

End_in (El)

End_Out

(EO)

Line_Separator (LS)

Determines if received characters are sent back to the remote host. ON indicates FULL duplex mode, OFF indicates HALF

duplex mode. Terminates the command message sent to the 7200A.

Be sure to use a value that is not included in the message itself, otherwise the 7200A will interpret it as the terminator.

Terminates the response message sent from the 7200A. One or two characters are used to represent the string. Unix-like

notation is used to represent control characters. For example,

\ r~ n is used to mean CR (decimal 13) followed by

(decimal 10)

CORS

of all settings.

Terminates a line of response, particularly useful for formatting a printout of block data. If OFF is selected, Line_Separator is not used.

See Also:

Line_Length

(EL)

Whenever the Line_Separator character(s) is encountered, the count for

the number of characters on a line is reset. Whenever the count exceeds

Line_Length, the Line_Separator is transmitted before the current charac-

ter.

Block Data, Command Syntax, WAVEFOFWI

Sets the maximum number of characters per line. If the Line_Separator occurs before the Line_Length is

reached, the line is terminated.

5-27

Mainframe Remote Commands

COMM_SCSI

Purpose: Sets or determines the SCSI id and block size to be used in transfers of

non-corrected acquisition data.

Command:

Query:. Response:

Arguments:

Example:

COSC keyword, value[,keyword,value] COSC? keyword[,keyword] COSC keyword,value[,keyword,value]

ID: Specifies the SCSI id of the device to which the acquired data are

to be sent. Choices are 0 to 7, excepting the SCSI id of the 7200A

itself.

BS: Specifies the number of bytes in each block to be transferred.

The last block may be smaller than the specifies block size, depending on the amount of data acquired. The block size can range from 4 to 65536 in increments of 2.

COSC ID, 6, BS, 2048 Sets ID= 6, block size= 2k

COSC? COSC ID,6, BS, 2048

Requests the current settings Returns current settings

COSC

5-28

Mainframe Remote Commands

COPY_FILE COPY

Purpose: Command:

Argument:

Copies the specified file(s) from the internal disk to the floppy or vice versa. COPY_FILE keyword,value The argument consists of a keyword followed by its value.

Keyword INPN

INAS

FLPY

Meaning: Value

Panel settings file on the internal disk to be copied

to the floppy disk.

=filename.ext" filename including extension

or =ALL FILES"

Program file on the internal disk to be copied to the floppy disk.

=filename.ext" filename including extension

or =ALL FILES"

Panel settings or program file on the floppy disk to be copied to the appropriate directory on the

internal disk.

"filename.ext" fllename including extension

or =ALL FILES"

Examples:

See Also:

COPY FLPY, "MIKE.PNL"

COPY INAS, "ALL FILES"

DIRECTORY_LIST, DELETEFILE

Copy the panel settings file MIKE.PNL from the floppy to the internal disk.

Copy all program files from the internal disk to the floppy disk

5-29

Mainframe Remote Commands

CURSOR LOCK

Purpose:

Command: Query:

Response: CURSOR_LOCK argument

Arguments:

Example:

Notes:

Allows you to choose to have independent parameter cursors for each trace or have all the cursors locked together so that they are on the same place on all the traces.

CURSOR_LOCK argument

CURSOR_LOCK?

The argument specifies whether to turn CURSOR_LOCK on or off:

ON Provides one parameter cursor for all of the traces. OFF

CURSOR_LOCK ON Selects one parameter cursor for all of the traces. CURSOR_LOCK? Returns the current status of of CURSOR_LOCK.

CURSOR_LOCK OFF

When using Histogram, you may want the cursors for all traces to be independent of each other. The reason for this is that if the cursors were locked

and you moved the cursors on the histogram, you may also be moving the cursors on the trace which is providing the input to the histogram and will therefore cause the histogram to be reset.

Provides an independent parameter cursor for each trace.

CRLK

Indicates cursor parameters may be set independently for each trace.

See Also:

EXPAR Extended Calculates up to 20 user selected parameters that

can be defined on any combination of traces.

OFF

CRMS? CRMS VREL

This command affects the display of cursors, it does not affect the

positioning of cursors (see CURSOR_SET) or their measurement (see CURSOR_VALUE).

CURSOR_SET, CURSOR_VALUE, PARAMETERVALUE, XY_CURSOR_SET, XY_CURSOR_VALUE, PER_CURSOR_SET,

PER_CURSOR_VALUE

Display no cursors.

Requests which cursors are currently displayed.

Reports that only the Vertical cursors are being displayed.

5-31

~inframe Remote Commands

CURSOR_SET

Purpose:

Command:

Query:. Response:

Arguments:

Positions any one of the eight independent cursors at a given screen location when not in XY or persistence mode. Cursor positions are specified relative to a grid. The positions of the cursors can be modified or queried

even if the required cursor is not currently displayed on the screen.

prefix:CURSOR SET keyword,position,...,keyword,positlon prefix:CURSOR_SET? keyword,keyword,keyword,...

prefix:CURSOR_SET keyword,position ..... keyword,position

prefix The prefix is limited to traces, i.e., T1, T2 ..... T8.

keyword,position ..... keyword, position

Cursor T.voe

Vertical Absolute VABS -4 to 4 DIV

Vertical Relative VREF, VDIF Marker Horizontal HREF, HDIF 0 to 10 DIV Basic PREF, PDIF 0 to 10 DIV Extended PREF, PDIF 0 to 10 DIV Unlocked UREF, UDIF 0 to 10 DIV

keyword position

-4 to 4 DIV

HABS

0 to 10 DIV, or Horizontal units

CRST

5-32

The seven cursor types measure the following: Verticial Absolute

Vertical Relative

Marker measures the absolute horizontal position and its

Horizontal measures the difference between the horizontal

Basic calculates a fixed set of waveform parameters on one

measures the absolute vertical value at a given point. measures the difference between vertical positions of

the cursors of a trace(s).

vertical value of a point on a trace(s).

positions and their corresponding vertical values of two Horizontal cursors

trace between two cursors

Mainframe Remote Commands

CURSOR_SET (continued)

Extended calculates up to 20 user selected waveform parameters that

can be defined on any combination of traces. Same as basic & Extended cursors but can be positioned

individually on each trace

Examples:

Note:

Unlocked

T1 :CRST HABS, 5 Races the marker in the center of the waveform.

T1 :CRST? HREF

"1"1 :CRST HREF, 2

Keywords ending in REF refer to a reference cursor which is a line of alternating dots and dashes. Keywords ending in DIF correspond to the

difference cursor which contains dashes. When positioning VREF and VDIF cursors and when the 7200A is display-

ing more than one grid, the specified position is interpreted as the number of divisions above or below the center of the grid on which the trace is currently displayed.

A command argument has two parts: keyword followed by position. Any number of arguments may be used in any order to change individual settings.

CRST

Requests the position of the horizontal reference

cursor on trace 1 The response indicates the position is two divisions

to the right of the grid’s left edge.

See Also:

If no arguments are specified with the query, all cursor positions are re-

turned. When querying the position, if the cursor is not on the specified trace, the

value UNDEF is returned. CURSOR_MEASURE, CURSOR_VALUE, PARAMETER_VALUE,

PER_CURSOR_SET, XY_CURSOR_SET

5-33

LeCroy 7200A Programmer's Guide

Specifications and Main Features

Frequently Asked Questions

User Manual

Section 5: Mainframe Remote Commands