Preface

Introduction to SCPI

Common SCPI commands

Instrument configuration and control commands

Other configuration and control commands

Acquisition of measurement data

Connection to the instrument using SCPI

Example of a simple measurement

Instrument programming in Python environment

Preface

Please refer to User Manual for general description of instrument operation, measurement principles and concepts.

Introduction to SCPI

SCPI (Standard Commands for Programmable Instruments) is a standardized set of text-based commands used to remotely control programmable test and measurement instruments. It defines the syntax and semantics that a controller must use to communicate with the instrument. This manual is an overview of SCPI and shows how SCPI is used in Pendulum CNT-104S instrument. SCPI is based on IEEE-488.2 to which it owes much of its structure and syntax.

Syntax and style

Syntax of Program Messages

In SCPI all messages that you can send to an instrument are divided into two categories: commands (that do not imply getting any response) and queries (that allow to get response back from the instrument). Queries have question mark ('?') at the end of command header.

A command or query is called a program message unit. A program message unit consists of a header followed by zero or more parameters:

<header> [parameter [,parameter ,...]]

For example, in the query

FETCH:ARRAY? MAX, A

FETCH:ARRAY is a header and MAX and A are parameters.

One or more program message units (commands) may be sent within a simple program message:

<program message unit>; <program message unit>; <program message unit>...

For example,

:INIT; *OPC?

Common Commands

SCPI standard defines a set of commands that every instrument must support. The common command header starts with the asterisk character (*), for example *RST.

SCPI Commands Tree

SCPI command headers may consist of several keywords (mnemonics), separated by the colon character (:).

Each keyword in a SCPI command header represents a node in the SCPI command tree. The leftmost keyword is the root level keyword, representing the highest hierarchical level in the command tree.
The keywords following represent subnodes under the root node.

Example: :SYST:CONF "Sample Interval=15ms"

In this example first colon (:) referers to the root of the tree. Next, SYST refers to an item under root, and CONF referes to an item under SYST.

SCPI commands syntax description used in this manual

Short and long forms

According to SCPI each command header can have short and long form. In order to distinguish both forms in command syntax description, upper and lower case characters are used. Note, that SCPI is case-insensitive, the usage of upper and lower case characters is done solely for the purpose of syntax definition. You may even mix upper and lower case. There is no semantic difference between upper and lower case in program messages. Same applies for parameters - they may have short and long forms.

Example 1. Let’s consider such syntax description: SYSTem:CONFigure <parameters>
Here SYST and CONF specify the short form, and SYSTem and CONFigure specify the long form. It means that the instrument will accept the following command headers: syst:conf , SYST:CONF , SYSTEM:CONFIGURE, SYST:CONFIGURE, or even sYstEm:cOnFiGuRE. However, SYSTE or CONFIG headers are not allowed and will cause a command error, because they don’t refer to short or long forms.

Example 2. Let’s consider such syntax description :FORMat[:DATA] <format> , where <format> is one of ASCii, REAL or PACKed. Such argument syntax indicates that the argument may be specified as: ASCII, ASC, asc, REAL, real, PACKED, pack, PACK.

Default nodes and arguments

SCPI standard states that some nodes in SCPI commands tree may play role of default nodes. That means that it is not required to specify them in command headers. Same applies for arguments. In this manual optional nodes and arguments are denoted with square brackets.

For example, let’s consider the following syntax description: :FETCh[:SCALar]? [<series name>]

Here square brackets indicate the fact that the node inside them (SCALAR) is default node under its parent node (FETCH). That means that you can specify the header as: :FETCH or :FETCH:SCALAR and result will be same. Same applies for parameters in square brackets. In this syntax <series name> parameter is marked as optional. Exact behavior of a command with omitted parameter is specified separately for each command.

Parameters

Each command defines which type of parameters it accepts.

Numeric Data

Decimal data. Numeric values that may contain both a decimal point and an exponent (base 10). Examples: 2.5, 1e-10, 5
Integer. Integer numbers.

Keywords

In addition to entering decimal data as numeric values, several keywords can exist. The manual explicitly specify which keywords are allowed by a particular command.

Boolean Data

A Boolean parameter specifies a single binary condition which is either true or false.
Boolean parameters can be one of the following:

ON or 1 means condition true.
OFF or 0 means condition false.

Other Data Types

String data. Always enclosed between single or double quotes, for example “This is a string” or ‘This is a string.’
Non-decimal data: For instance, #H3A for hexadecimal data.
Block data: Used to transfer any 8-bit coded data. This data starts with a preamble that contains information about the length of the parameter.

Common SCPI commands

SCPI standard requires that all instrument support a set of common commands and queries. Such commands are described in next paragraphs.

*CLS

Clear Status Command

The *CLS common command clears the status data structures by clearing all event registers and the error queue. It does not clear enable registers. It clears any pending *WAI, *OPC, and *OPC?.

Example:

Send: → *CLS

*ESE

*ESE <integer>

*ESE?

Standard Event Status Enable

Sets or reads out the enable bits of the standard event enable register. This enable register contains a mask value for the bits to be enabled in the standard event status register. A bit that is set true in the enable register enables the corresponding bit in the status register. An enabled bit will set the ESB (Event Status Bit) in the Status Byte Register if the enabled event occurs.

Parameters: <integer> = the sum (between 0 and 255) of all bits that are true.

Event Status Enable Register (1 = enable)
Bit	Weight	Enables
7	128	Reserved
6	64	Reserved
5	32	Reserved
4	16	Reserved
3	8	Reserved
2	4	Reserved
1	2	Reserved
0	1	Operation Complete

Returned Format: <integer> \n

Example:

SEND → *ESE 1

In this example, bit 0 (Operation Complete event) is enabled. This will set the “ESB” bit of the Status Byte Register when long operation completes.
SEND → *ESE?
Reply: 1

*ESR?

Event Status Register.

Reads out the contents of the standard event status register. Reading the Standard Event Status Register clears the register.
Returned Format: <integer> = the sum (between 0 and 255) of all bits that are true.

*IDN?

Identification query

Reads out the manufacturer, model, serial number, and firmware level in an ASCii response data element. The query must be the last query in a program message.

Response is <Manufacturer>, <Model> , <Serial Number>, <Firmware Level>.

Example:

SEND → *IDN?

READ ← Pendulum, CNT-104S, 000024, v1.1.1 2022-11-24

*OPC

Operation Complete

The Operation Complete command causes the device to set the operation complete bit in the Standard Event Status Register when all pending selected device operations have been finished.

*OPC?

Operation Complete Query.

Operation Complete query. The Operation Complete query places an ASCii character 1 into the device’s Output Queue when all pending selected device operations have been finished.

Returned Format: 1 \n

*OPT

Option Identification

Response is a list of all detectable options present in the instrument. When no options are present response is ASCII ‘0’:
<Prescaler option (if present)>, <Oscillator code>, <SW option>, <SW option>…

<Prescaler option> = 10 3GHz / 110 10Ghz / 110/15 15GHz / 110/20 20GHz / 110/24 24GHz.

<Prescaler option> represents maximum frequency that a user is allowed to measure using currently installed HW and SW license option.

<Oscillator code> = TCXO / OCXO30 / OCXO40.

*RST

Reset

The Reset command resets the instrument. The settings will be set to the default, except settings in Network, Date/Time, Display groups. All previous commands are discarded and the counter is prepared to start new operations.

It is a good practice to start working with the instrument by issuing this command to ensure all settings are in known default state.

Example: *RST

Send: → *RST

*SRE

*SRE <integer>

*SRE?

Service Request Enable

The Service Request Enable command sets/reads the service request enable register bits. This enable register contains a mask value for the bits to be enabled in the status byte register. A bit that is set true in the enable register enables the corresponding bit in the status byte register to generate a Service Request.

Parameters: <integer> = the sum (between 0 and 255) of all bits that are true

See table below:

Service Request Enable Register (1 = enable)
Bit	Weight	Enables
7	128	OPR, Operation Status
6	64	RQS, Request Service
5	32	ESB, Event Status Bit
4	16	MAV, Message Available
3	8	QUE, Questionable Data/Signal Status
2	4	EAV, Error Available
1	2	Reserved
0	1	Reserved

Returned Format: <integer>

Where:

<integer> = the sum of all bits that are set.

Example: *SRE 16

In this example, the counter generates a service request when a message is available in the output queue.

*STB?

Status Byte Query

Reads out the value of the Status Byte. Bit 6 reports the Master Summary Status bit (MSS), not the Request Service (RQS). The MSS is set if the instrument has one or more reasons for requesting service.

Returned Format:

<Integer> = the sum (between 0 and 255) of all bits that are true. See table below:

Status Byte Register (1 = true)
Bit	Weight	Name	Condition
7	128	OPR	Enabled operation status has occurred
6	64	MSS	Reason for requesting service
5	32	ESB	Enabled status event condition has occurred
4	16	MAV	An output message is ready
3	8	QUE	The quality of the output signal is questionable
2	4	EAV	Error available
1	2		Reserved
0	1		Reserved

See also: If you want to read the status byte with the RQS bit, use serial poll.

*WAI

Wait-to-continue

The Wait-to-Continue command prevents the device from executing any further commands or queries until execution of all previous commands or queries has been completed.

Instrument configuration and control commands

:INITiate

Initiate (start) a measurement

Command syntax:

:INITiate

Description

This command starts a measurement. Measurement settings must be configured before starting a measurement using SYSTEM:CONFIGURE command. After measurement is complete the instrument doesn’t automatically start any new measurement.

:SYSTem:CONFigure

Configure measurement (and other) settings.

Command syntax

:SYSTem:CONFigure <parameters_in_quoted_string>

Where <parameters_in_quoted_string> is a quoted string of key-value pairs like "<param1> = <value1>; <param2> = <value2>; ..."

where param1, param2 are configuration keys and value1, value2 are corresponding configuration values.

Query syntax

:SYSTem:CONFigure? <category>

where <category> is one of

ALL - to get all settings

MEASure - to get only measurement-related settings

NETwork - to get Ethernet interface settings

Query response format

parameters_in_quoted_string in the same format as for command syntax. Only settings belonging to specified category are returned.

Description

Both command parameter and query response represent a quoted string of various settings for the device. The settings are given as key-value pairs separated by semicolon (';') inside quoted string.

When you start programming an instrument that may have unknown configuration, it’s always a good idea to bring the instrument to a default state by sending: *RST; *CLS .This will ensure that all measurement settings are reset to defaults and that error and message buffers are cleared.

SYST:CONF command may be used several times in a raw. The command never changes (adjusts) other (not mentioned) settings implicitly. Neither they are reset to default values. When you want to perform two measurements with very different settings, you may want to use *RST command to reset all settings to known defaults before making new configuration.

If given settings are not compatible with previously configured settings or a command has other problems (e.g. parameters out of allowed range), command execution will result in an error and no new settings will be applied. In other words, the command will either successfully apply all specified settings or will not change instrument configuration at all. Such behavior allows to ensure that the instrument configuration is always in a known predictable state. To check for possible configuration errors use SYSTEM:ERROR? query immediately after configuring the instrument with SYSTEM:CONFIGURE.

Example

SEND → :SYST:CONF "CouplingA=DC; FilterA=100kHz; SampleInterval=500us; SampleCount=10; Function=Positive Pulse Width A"

Configuration parameters for :SYSTEM:CONFIGURE

TriggerMode

This parameter specifies how the instrument selects trigger levels for measurement comparators. Trigger levels can be set automatically by the instrument or specified by the user.

Parameter syntax: TriggerMode<Input>

where <Input> is one of A, B, D, E, for example: TriggerModeA

Possible values: Auto, Relative, Manual

Default value (RST condition): Auto

Description

Auto- Preliminary voltage measurement will be performed to find out signal voltage range and set trigger levels to best values for selected measurement function.

Depending on measurement function selected trigger levels will be automatically set to percentage values of signal voltage range:

10% for the main comparator, 90% for the supplementary comparator for signal edge related functions: RiseTime/FallTime/RiseFallTime/PositiveSlewRate/NegativeSlewRate
70% for the main comparator, 30% for the supplementary comparator for the functions with hysteresis on: Frequency/FrequencyRatio/frequencySmart/PeriodAverage/PeriodAverageSmart/TIE
50% for both main and supplementary comparators for all other functions

Relative- Preliminary measurement is preformed, but you can adjust trigger levels relative to the measured signal voltage range, in percents, using RelativeTriggerLevel parameter.

Manual- Trigger levels are set accordingly to values specified by AbsoluteTriggerLevel parameter. It is recommended to use this mode only in cases when Autoset fails to find the best settings.

Example:

SYST:CONF "TriggerModeA=Auto"

AbsoluteTriggerLevel

Set absolute trigger levels for main and supplementary comparators

Parameter syntax: AbsoluteTriggerLevel<Comparator>

where <Comparator> is one of A, A2, B, B2, D, D2, E, E2. For example: AbsoluteTriggerLevelA2

Possible values:

Any floating point number representing trigger level in Volts, withing voltage measurement range. Voltage measurement range depends on Attenuation and Preamplifier parameters. See description of Attenuation and Preamplifier parameters.

Default value (RST condition): 0

Description

Sets trigger level in volts on main comparator (if numeric index is omitted, for example: A, B, D, E) or on supplementary comparator (if numeric index is 2, for example: A2, B2, D2, E2) of the input. Main comparator is used for all measurements performed on input, generating events to internal measurement core whenever signal crosses set trigger level. Supplementary comparator can be selected explicitly for some measurements from input (e.g. Time Interval A, A2), generating independent events to internal measurement core whenever signal crosses set trigger level. Otherwise it is used implicitly for frequency average and period average measurements (to assure wide hysteresis), for Rise & Fall Time and Slew Rate.

Example:

SEND → SYST:CONF "TriggerModeA=Manual; AbsoluteTriggerLevelA=-2.5; AbsoluteTriggerLevelA2=2.5; TriggerModeB=Manual; AbsoluteTriggerLevelB=0; AbsoluteTriggerLevelB2=1.35"

RelativeTriggerLevel

Sets relative trigger levels in percents relative to signal voltage range, for main and supplementary comparators.

Parameter syntax: RelativeTriggerLevel<Comparator>

where <Comparator> is one of A, A2, B, B2, D, D2, E, E2. For example: RelativeTriggerLevelB2

Possible values: 0 … 100

Default value (RST condition):

70 for the main comparators

30 for the supplementary comparators

Description

Sets trigger level on main (if comparator index is omitted, e.g. just A) or on supplementary comparator (if comparator index is 2, e.g. A2) of input in percents relative to measured signal voltage range. 0% corresponds to signal min value and 100% corresponds to signal max value. Main comparator is used for all measurements performed on input, generating events to internal measurement core whenever signal crosses set trigger level. Supplementary comparator can be selected explicitly for some measurements generating independent events to internal measurement core whenever signal crosses set trigger level. Otherwise it is used implicitly for frequency average and period average measurements (to assure wide hysteresis), for Rise & Fall Time and Slew Rate.

Example

SEND → SYST:CONF "TriggerModeA=Relative; RelativeTriggerLevelA=65; RelativeTriggerLevelA2=35"

Slope

Specifies signal slope that triggers comparator

Parameter syntax: Slope<Comparator>

where Comparator is one of A, A2, B, B2, C, D, D2, E, E2, EA, ER, G, T

Possible values: Positive, Negative

Default value (RST condition): Positive

Description

Positive- Positive slope is used for corresponding input

Negative - Negative slope is used for corresponding input

Example

SYST:CONF "SlopeA=Positive"

Impedance

Specifies input impedance

Parameter syntax: Impedance<Input>

where <Input> is one of A, B, D, E. For example: ImpedanceA

Possible values: 50Ohm, 1MOhm

Default value (RST condition): 1MOhm

Description

50Ohm - 50 Ohm impedance is used for corresponding input

1MOhm - 1 MOhm impedance is used for corresponding input

Example

SEND → SYST:CONF "ImpedanceA = 50 Ohm"

Coupling

Allows to select AC or DC coupling of an input.

Parameter syntax: Coupling<Input>

where <Input> is one of A, B, D, E. For example: CouplingA

Possible values: DC, AC

Default value (RST condition): AC

Description

AC coupling allows to block unnecessary DC offset that may be present in the signal.

DC - DC coupling is used for corresponding input

AC - AC coupling is used for corresponding input

Example

SEND → SYST:CONF "CouplingA = AC"

Filter

Selects whether low-pass filter is enabled for an input

Parameter syntax: Filter<Input>

where Input is one of A, B, D, E. For example: FilterA

Possible values: Off, 10kHz, 100kHz

Default value (RST condition): Off

Description

Off - Filter is not used for corresponding input

10kHz - 10 kHz low pass filter is used for corresponding input

100kHz - 100 kHz low pass filter is used for corresponding input

Example

SYST:CONF "FilterA = Off"

Attenuation

Enables or disables signal attenuation on an input

Parameter syntax: Attenuation<Input>

where Input is one of A, B, D, E. For example: AttenuationA

Possible values: 1x, 10x, Auto

Default value (RST condition): 1x

Description

This setting allow to enable attenuation for situations when measurement signal amplitude is too big for an input.

1x - 1x attenuation is used for corresponding input (corresponds to no attenuation)

10x - 10x attenuation is used for corresponding input (signal is decreased 10 times).

Auto - Attenuation is auto-selected is used for corresponding input.

Correct auto-trigger operation operation and voltage measurements are possible for the following input signal voltage ranges depending on attenuation and preamplifier settings.

	Preamplifier=off	Preamplifier=on
Attenuation=1x	-5 … +5 V	-1.5 .. +1.5 V
Attenuation=10x	-50 ... +50 V	-15 .. +15 V
Attenuation=Auto	-50 ... +50 V	-1.5 .. +1.5 V

Note! When measuring voltage-related signal characteristics, measurement results displayed on the screen and provided by SCPI queries are not decreased 10 times when attenuation is enabled. Even though the signal is attenuated inside the instrument, resulting data are scaled back to original scale.

Example

SYST:CONF "AttenuationA = 10x"

Preamplifier

Enables or disables signal amplification inside the instrument for an input.

Parameter syntax: Preamplifier<Input>

where Input is one of A, B, D, E. For example: PreamplifierA

Possible values: Off, On

Default value (RST condition): Off

Description

Allows to amplify input signal. It is recommended to turn amplification on only if input signal has low amplitude.

Off - Preamplifier in off for corresponding input

On - Preamplifier in on for corresponding input

Correct auto-trigger operation and voltage measurements are possible for the following input signal voltage ranges depending on attenuation and preamplifier settings.

	Preamplifier=off	Preamplifier=on
Attenuation=1x	-5 … +5 V	-1.5 .. +1.5 V
Attenuation=10x	-50 ... +50 V	-15 .. +15 V
Attenuation=Auto	-50 ... +50 V	-1.5 .. +1.5 V

Example

SYST:CONF "PreamplifierA = On"

ArmOn

When arming is enabled, defines whether sample block or each sample within the block should be armed.

Parameter syntax: ArmOn

Possible values: Block, Sample

Default value (RST condition): Block

Description

When arming is enabled, defines whether sample block or each sample within the block should be armed. Block of samples is a group of samples captured during a measurement (number of samples is defined by SampleCount parameter). This setting is available for modification only when arming is enabled. See StartArmingSource parameter.

Block - Arm on Block mode: entire sample block is being armed. Please note: when arming on Block and stop arming is not Off - the resulting number of samples in the block might be less than SampleCount.

Sample - Arm on Sample mode: each individual sample inside the block is being armed.

Example

SYST:CONF "ArmOn = Block"

Function

Selects measurement function and inputs

Parameter syntax: Function=<function name> <input_or_comparator>[,<input_or_comparator>, ...]

where

<function name> is one of Frequency, SmartFrequency, PeriodAverage, SmartPeriodAverage, PeriodSingle, TimeInterval, TimeIntervalSingle, AccumulatedTimeInterval, Phase, AccumulatedPhase, TIE, PositiveDutyCycle, NegativeDutyCycle, PositivePulseWidth, NegativePulseWidth, RiseTime, FallTime, RiseFallTime, PositiveSlewRate, NegativeSlewRate, Totalize, TotalizeX+Y, TotalizeX-Y, TotalizeX/Y, Vmin, Vmax, Vpp, Vminmax, DC Offset

input_or_comparator is one of A, A2, B, B2, C, D, D2, E, E2, EA, ER, G, T. See description below for limitations.

Possible values:

Note, that this parameter is combination of function name, space character and a list of inputs/comparators, separated by comma. Each measurement function supports different maximum number of inputs or comparators. See description below for possible values, their meanings and limitations.

Default value (RST condition): Frequency A

Description

Allows to select measurement function of the instrument.

`<function name>`	Description
`Frequency`	Average frequency over gate time (set by Sample Interval parameter). This is back-to-back measurement (every period of the signal can be captured) for frequencies up to 20 MHz. Up to 4 signals can be measured in parallel. All inputs/comparators can be used.
`FrequencyRatio`	Ratio of frequency averages. This mode is just additional math applied over frequency measurements.All inputs/comparators can be used. Minimum two inputs/comparators must be specified. When two inputs/comparators are specified then the frequency ratio of second to first input/comparator is measured. When three inputs/comparators are specified then ratios of 2nd to 1st and 3rd to 1st are measured. When 4 inputs/comparators are specified then ratios of 2nd to 1st and 4th to 3rd are measured.
`SmartFrequency`	Smart Frequency function makes use of regression analysis to increase the resolution of the measurement at the expense of measurement speed. Please, note: this mode assumes signal frequency is static within gate time (set by Sample Interval). All inputs/comparators can be used.
`PeriodAverage`	Average period over gate time (set by Sample Interval parameter). This is back-to-back measurement (every period of the signal can be captured) for frequencies up to 20 MHz. Up to 4 signals can be measured in parallel. All inputs/comparators can be used.
`SmartPeriodAverage`	Smart Period Average function makes use of regression analysis to increase the resolution of the measurement at the expense of measurement speed. Please, note: this mode assumes signal frequency is static within gate time (set by Sample Interval parameter). All inputs/comparators can be used.
`PeriodSingle`	Allows to capture single signal periods for periods less than 20 MHz at expense of 50 ns dead-time.All inputs/comparators can be used. Maximum is 2 inputs.
`TimeInterval`	Time Interval between up to 4 periodic signals. Result is normalized to the range of -0.5 to +1 signal period.All inputs except C can be used.
`TimeIntervalSingle`	Time Interval between single events from up to 4 inputs.All inputs except C can be used.
`AccumulatedTimeInterval`	Same as Time Interval, but the result is not normalized.All inputs except C can be used.
`Phase`	Phase difference between 2 periodic signals. Result is normalized to the range of -180° to +360°.All inputs except C can be used.
`AccumulatedPhase`	Same as Phase, but the result is not normalized.All inputs except C can be used.
`TIE`	Time Interval Error (TIE) between up to 4 independent clock sources.All inputs can be used.
`PositiveDutyCycle`	Ratio of a pulse signal Positive Pulse Width to its Period.Inputs A, B, D, E can be used. One input only.
`NegativeDutyCycle`	Ratio of a pulse signal Negative Pulse Width to its Period.Inputs A, B, D, E can be used. One input only.
`PositivePulseWidth`	Positive Pulse Width of a pulse signal.Inputs A, B, D, E can be used. Maximum is 2 inputs.
`NegativePulseWidth`	Negative Pulse Width of a pulse signal.Inputs A, B, D, E can be used. Maximum is 2 inputs.
`RiseTime`	Measures how much time it takes for the signal to go from 10% to 90% of its voltage range.Inputs A, B, D, E can be used. Maximum is 2 inputs.
`FallTime`	Measures how much time it takes for the signal to go from 90% to 10% of its voltage range.Inputs A, B, D, E can be used. Maximum is 2 inputs.
`RiseFallTime`	Measures how much time it takes for the signal to go from 10% to 90% of its voltage range and back.Inputs A, B, D, E can be used. One input only.
`PositiveSlewRate`	Measures how fast signal voltage increases from 10% to 90% of its range.Inputs A, B, D, E can be used. Maximum is 2 inputs.
`NegativeSlewRate`	Measures how fast signal voltage decreases from 90% to 10% of its range.Inputs A, B, D, E can be used. Maximum is 2 inputs.
`Totalize`	Counts number of events on up to 4 input channels in parallel.All inputs except C can be used.
`TotalizeX+Y`	Totalize with additional maths applied.All inputs except C can be used. Minimum is 2 inputs.
`TotalizeX-Y`	Totalize with additional maths applied.All inputs except C can be used. Minimum is 2 inputs.
`TotalizeX/Y`	Totalize with additional maths applied.All inputs except C can be used. Minimum is 2 inputs.
`Vmin`	Minimum voltage level of a signal.Inputs A, B, D, E can be used.
`Vmax`	Maximum voltage level of a signal.Inputs A, B, D, E can be used.
`Vpp`	Signal maximum and minimum voltage levels difference.Inputs A, B, D, E can be used.
`Vminmax`	Minimum and maximum voltage levels of a signal.Inputs A, B, D, E can be used. One input only.
`DC Offset`	Measure DC offset voltage of a signal. Note: DC coupling must be enabled for corresponding input.

Example

:SYST:CONF "Function = Frequency A"

:SYST:CONF "Function=Period Average A,B2,EA"

HoldOff

Dead time between consecutive trigger events

Parameter syntax: HoldOff

Possible values: 0 - 2.683 s

Default value (RST condition): 0 s

Description

Adds dead time between consecutive trigger events. Used to cope with contact bouncing or signal oscillations.

Example

SYST:CONF "HoldOff = 0.555 s"

LimitBehaviour

Enables of disables limits for measurements. Defines instrument behavior when specified limits are exceeded.

Parameter syntax: LimitBehaviour

Possible values: Off, Capture, Alarm, AlarmStop

Default value (RST condition): Off

Description

Defines how the instrument will react on limits. Limit criterion is set by Limit Type, Upper Limit and Lower Limit. For all limit behavior choices except Off the following is true: If measured value has fell off the limit criterion during measurement session then red exclamation mark indicator is displayed.

Off- Limits are disabled.

Capture - Only samples meeting the limit criterion are captured, the rest are discarded. Limit status is displayed

Alarm - All samples are captured, limit status is displayed

AlarmStop - Measurement session stops if measured value doesn't meet the limit criterion

Example

SYST:CONF "LimitBehaviour = Alarm"

LimitLower

Specifies lower limit.

Parameter syntax: LimitLower

Possible values: any decimal

Default value (RST condition): 0

Description

Lower limit (used if LimitType=Above or LimitType=Range and LimitBehaviour is not Off)

Example

SYST:CONF "LimitLower = 0 Hz"

LimitSeriesName

Specifies name of series for which limit is applies to.

Parameter syntax: LimitSeriesName

Possible values: All, A,B,A/B,A+B,Vmin, etc.

Default value (RST condition): All

Description

Name of the series that the limit is applied to, or “All“ if applied to all series. This parameter can be used only when limits are enabled (LimitBehaviour is not Off)

Example

SYST:CONF "LimitSeriesName = A/B"

LimitType

Specifies limit type.

Parameter syntax: LimitType

Possible values: Above, Below, Range

Default value (RST condition): Above

Description

Above- Results above set Lower Limit will pass

Below - Results below set Upper Limit will pass

Range - Results within the set limits will pass

This parameter can be used only when limits are enabled (LimitBehaviour is not Off)

Example

SYST:CONF "LimitType = Range"

LimitUpper

Specifies upper limit

Parameter syntax: LimitUpper

Possible values: any decimal

Default value (RST condition): 0

Description

Upper limit (used if LimitType=Below or LimitType=Range and LimitBehaviour is not Off)

Example

SYST:CONF "LimitUpper = 24.7 Hz"

MathCoeffK, MathCoeffL, MathCoeffM

Specifies values for coefficients K, L, M, when mathematical formula is enabled.

Parameter syntax: MathCoeff<Coefficient>

where Coefficientis one of K, L, M,. For exampe: MathCoeffL

Default value (RST condition):

MathCoeffK = 1

MathCoeffL = 0

MathCoeffM = 1

Description

K, L, M constants used in Math formula.

Example

SYST:CONF "MathCoeffM = 1"

MathCustomUnit

Overrides result units when mathematical formula is applied.

Parameter syntax: MathCustomUnit

Description

When math formula is applied, measurement results units are usually determined automatically. This parameter allows to override the unit of the value after math formula is applied. The length of the custom unit must not exceed 4 characters

Example

SYST:CONF "MathCustomUnit = Emu"

MathMode

Selects mathematical formula to apply for results

Parameter syntax: MathMode

Possible values: Off, K*X+L, K/X+L, (K*X+L)/M, (K/X+L)/M, X/M-1

Default value (RST condition): Off

Description

Allows to apply math over measurement results. Please note, some of available formulae change unit of original value.

Example

SYST:CONF "MathMode = K/X+L"

MathSeriesName

Select series to apply math formula to.

Parameter syntax: MathSeriesName

Possible values: All, A, B, A/B, A+B, Vmin, etc.

Default value (RST condition): All

Description

Name of the series that MathMode is applied to, or “All“ if applied to all series

Example

SYST:CONF "MathSeriesName = A+B"

PulseOutputMode

Controls the rear Pulse Output of the device.

Parameter syntax: PulseOutputMode

Possible values: Off, PulseGenerator, GateOpen, AlarmOutActiveHigh, AlarmOutActiveLow

Default value (RST condition): Off

Description

Controls the rear Pulse Output of the instrument. The amplitude is set to TTL levels into 50 Ohm irrespective to output mode.

Off- No signal on Pulse Output

PulseGenerator - Continuous pulse train with period and pulse width set in next menus

GateOpen - Indicates when measurement is in progress

AlarmOutActiveHigh - High level output when limits alarm is active, low level otherwise

AlarmOutActiveLow - Low level output when limits alarm is active, high level otherwise

Example

SYST:CONF "PulseOutputMode = AlarmOutActiveLow"

PulseOutputPeriod

Set period of pulses generated on rear Pulse Output of the instrument.

Parameter syntax: PulseOutputPeriod

Possible values: 10 ns .. 2.147 s

Default value (RST condition): 1 ms

Description

Set period of pulses generated on Pulse Output if Mode is set to Pulse Generator. Resolution for this parameter is 2 ns.

Example

SYST:CONF "PulseOutputPeriod = 12 ns"

PulseOutputWidth

Set width of pulses generated on rear Pulse Output of the instrument.

Parameter syntax: PulseOutputWidth

Possible values: 4 ns .. 2.146999994 s (but at least 6 ns lower than PulseOutputPeriod)

Default value (RST condition): 500 us

Description

Set width of pulses generated on Pulse Output if Mode is set to Pulse Generator. Resolution for this parameter is 2 ns. Should be at least 6 ns less than PulseOutputPeriod.

Example

SYST:CONF "PulseOutputWidth = 2.1 s"

SampleCount

Defines number of samples to be collected for each measurement series.

Parameter syntax: SampleCount

Possible values: up to 31999999 samples (depends on selected function and inputs/comparators and other settings)

Default value (RST condition): 1

Description

Defines number of samples to be collected for each measurement series.

Example

SYST:CONF "SampleCount = 10000"

SampleInterval

Specifies how often measurement samples are generated and/or define gate time.

Parameter syntax: SampleInterval

Default value (RST condition): 10 ms

Description

Defines gate time for Frequency measurement. Please note, that if signal period is larger than this value then actual sample interval will be equal to signal period.

For Frequency, Sample Interval should be in the range: 1 us .. 10.995 ks Please note: to allow sample interval below 1 us corresponding license is required.

Example

SYST:CONF "SampleInterval = 10 ms"

SignalSource

Specifies whether to use input signals for measurement or internal test generator.

Parameter syntax: SignalSource

Possible values: Inputs, Test

Default value (RST condition): Inputs

Description

Built-in test signal generator is used for performing internal device calibrations but can also be used for testing purposes. This setting must be used only for testing or demonstrational purposes when there is no possibility to connect external source of signal to instrument’s inputs.

Inputs- Normal operation

Test - Using internal test signal generator instead of inputs on front (back) panel. Output of the internal generator are connected to inputs A, B, D, E and can be measured. Please, note: test generator is using independent coarse time base and is not expected to provide accurate frequency. It is not the same generator which drives rear Pulse Output of the device.

Example

SYST:CONF "SignalSource = Test"

StartArmingDelay

Delay for making measurement after arming event.

Parameter syntax: StartArmingDelay

Default value (RST condition): 0 s

Description

Defines time after start arming event when measurement should be started. Start Arming Delay should be in the range: 0 s .. 10.995 ks

Example

SYST:CONF "StartArmingDelay = 8.556 ks"

StartArmingSlope

Signal slope to use as arming event.

Parameter syntax: StartArmingSlope

Possible values: Positive, Negative

Default value (RST condition): Positive

Description

Slope which arms measurement

Negative- Negative slope is used for Start Arming

Positive - Positive slope is used for Start Arming

Example

SYST:CONF "StartArmingSlope = Negative"

StartArmingSource

Input or comparator that will be used to detect arming event.

Parameter syntax: StartArmingSource

Possible values: Off, EA, A, B, D, E, A2, B2, D2, E2

Default value (RST condition): Off

Description

Defines whether signal from one of device inputs should be used to arm start of measurement.

Example

SYST:CONF "StartArmingSource = A"

StopArmingDelay

Delay for stopping measurement after stop arming event.

Parameter syntax: StopArmingDelay

Default value (RST condition): 0 s

Description

Defines time after stop arming event when measurement should be stopped. Stop Arming Delay should be in the range: 0 s .. 10.995 ks

Example

SYST:CONF "StopArmingDelay = 6.652 ks"

StopArmingSlope

Signal slope to use as stop arming event.

Parameter syntax: StopArmingSlope

Possible values: Positive, Negative

Default value (RST condition): Positive

Description

Slope which arms measurement stop

Negative- Negative slope is used for Stop Arming

Positive - Positive slope is used for Stop Arming

Example

SYST:CONF "StopArmingSlope = Negative"

StopArmingSource

Input or comparator to use for stop arming event detection.

Parameter syntax: StopArmingSource

Possible values: Off, EA, A, B, D, E, A2, B2, D2, E2

Default value (RST condition): Off

Description

Defines whether signal from one of device inputs or timer should be used to stop measurement.

Example

SYST:CONF "StopArmingSource = B2"

TestSignalFrequency

Frequency of internal built-in test generator.

Parameter syntax: TestSignalFrequency

Possible values: 1.039 kHz .. 68 MHz

Default value (RST condition): 1 MHz

Description

Sets frequency of built-in test generator. Please, note: test generator is using independent coarse timebase and is not expected to provide accurate frequency. It is not the same generator which drives rear Pulse Output of the device. Test Signal Frequency should be in the range: 1.039 kHz .. 68 MHz

Example

SYST:CONF "TestSignalFrequency = 5.555 kHz"

TieReferenceFrequency A, A2, B, B2, D, D2, E, E2, EA, ER

Reference frequency for input or comparator when doing TIE measurements.

Parameter syntax: TieReferenceFrequency<Input>

where Input is one of A, A2, B, B2, D, D2. For example: TieReferenceFrequencyA

Possible values: 100 mHz .. 400 MHz

Default value (RST condition): 10 MHz

Description

Reference frequency for input A, A2, B, B2, D, D2, E, E2, EA, ER. Should be in the range: 100 mHz .. 400 MHz

Example

SYST:CONF "TieReferenceFrequencyB = 101 mHz"

TieReferenceFrequencyC

Reference frequency for input C when doing TIE measurements.

Parameter syntax: TieReferenceFrequencyC

Possible values: 100 mHz .. 24 GHz

Default value (RST condition): 1 GHz

Description

Reference frequency for input C. Ref Frequency for input C should be in the range: 100 mHz .. 24 GHz

Example

SYST:CONF "TieReferenceFrequencyC = 12 GHz"

TieReferenceFrequencyDetection

Defines if reference frequency is detected automatically or should be set manually

Parameter syntax: TieReferenceFrequencyDetection

Possible values: On, Off

Default value (RST condition): On

Description

Defines if reference frequency is detected automatically or should be set manually

On- Reference frequency for TIE measurement is detected automatically

Off - Reference frequency for TIE measurement is set manually

Example

SYST:CONF "TieReferenceFrequencyDetection = Off"

TieReferenceFrequencyNumberOfDigits

Number of digits detected reference frequency should be rounded to.

Parameter syntax: TieReferenceFrequencyNumberOfDigits

Possible values: 0-10

Default value (RST condition): 5

Description

Defines how many digits detected reference frequency should be rounded to. Ref Frequency Number Of Digits should be in the range: 0 .. 10

Example

SYST:CONF "TieReferenceFrequencyNumberOfDigits = 9"

TimebaseReference

Specifies which reference clock to use for measurements.

Parameter syntax: TimebaseReference

Possible values: Auto, Internal, External

Default value (RST condition): Auto

Description

Defines which reference clock will be used for measurement.

Internal - Internal timebase reference is used

External - External timebase reference is used if it is connected and within expected parameters, otherwise measurement is not performed.

Auto- External timebase reference is used if it is connected and within expected parameters, otherwise internal

Example

SYST:CONF "TimebaseReference = External"

Timeout

Enable of disable measurement timeout.

Parameter syntax: Timeout

Possible values: On, Off

Default value (RST condition): Off

Description

Used to make measurement session to end if signal is missing for more than specified Timeout Time.

On- Timeout is on

Off - Timeout is off

Example

SYST:CONF "Timeout = Off"

TimeoutTime

Set measurement timeout value.

Parameter syntax: TimeoutTime

Possible values: 10 ms .. 1 ks

Default value (RST condition): 100 ms

Description

If Timeout is On, measurement session ends if signal is missing for more than specified Timeout Time.

Example

SYST:CONF "TimeoutTime = 168 ms"

VoltageMode

* * * * * * * * * * * * * *

Parameter syntax: VoltageMode

Possible values: Normal, VerySlow, Slow, Fast, VeryFast

Default value (RST condition): Normal

Description

Defines minimal signal frequency for which voltage measurements and/or auto-trigger works correctly. Please, note: voltage/auto-trigger for lower frequencies are measured at the expense of measurement speed. It is recommended to treat this setting as a fallback for the cases where Autoset fails to find best setting automatically.

VerySlow - Used for signals with frequency in range: < 10 Hz

Slow- Used for signals with frequency in range: 10 Hz to 100 Hz

Normal- Used for signals with frequency in range: 100 Hz to 1 kHz

Fast - Used for signals with frequency in range: 1 kHz to 10 kHz

VeryFast - Used for signals with frequency 10 kHz and above.

DC signals can be measured with any mode.

Example

SYST:CONF "VoltageMode = Fast"

InternalCalibrationMode

Defines when to start internal calibration.

Parameter syntax: InternalCalibrationMode

Possible values: Every30Min, BeforeEveryMeasurement, OnceAfterWarmup

Default value (RST condition): Every30Min

Description

Internal calibration is always done on device start-up and after it has warmed up. More frequent calibration can be done in order to improve timing measurement resolution.

Every30Min - Additional calibration every 30 minutes

BeforeEveryMeasurement- Additional calibration before every measurement

OnceAfterWarmup- No additional calibration

Example

SYST:CONF "InternalCalibrationMode = Every30Min"

NumOfBlankDigits

Number of digits to blank on display.

Parameter syntax: NumOfBlankDigits

Possible values: 0 .. 15

Default value (RST condition): 0

Description

Defines the number of least significant digits to be masked. This can be used to help operator to read out the results of jittery measurements. Please note: it applies only to the current measured value, not statistics. Digits Blank should be in the range: 0 .. 15

Example

SYST:CONF "NumOfBlankDigits = 12"

ScreenSaverTimeout

Timeout to switch off display.

Parameter syntax: ScreenSaverTimeout

Possible values: 5minutes, 10minutes, 30minutes, 1hour, Never

Default value (RST condition): 10minutes

Description

Inactivity timeout for turning device display off

5minutes - Inactivity timeout set to 5 minutes

105minutes- Inactivity timeout set to 10 minutes

305minutes- Inactivity timeout set to 30 minutes

1hour- Inactivity timeout set to 1 hour

Never- Device display is always on

Example

SYST:CONF "ScreenSaverTimeout = Never"

Brightness

Display brightness.

Parameter syntax: Brightness

Possible values: Minimum, Low, Medium, High, Maximum

Default value (RST condition): Maximum

Description

Inactivity timeout for turning device display off

Minimum - Minimum brightness

Low- Low brightness

Medium- Medium brightness

High- High brightness

Maximum- Maximum brightness

Example

SYST:CONF "Brightness = Minimum"

Wired and Wireless network settings

IPAddress/WirelessIPAddress

Specifies static (manual) IPv4 address in Ethernet network

Parameter syntax: IPAddress, WirelessIPAddress

Possible values: IP address (four numbers, dot-separated)

Default value (RST condition): 192.168.0.99

Description

IP address for Ethernet interface when static IP address mode is enabled in IPMode parameter. When DHCP mode is enabled, the IP is assigned by a DHCP server in network and can be read back with SYST:CONF? query)

IP address for Wireless interface (with DHCP, configured address can be read back)

Example

SYST:CONF "IPAddress = 192.168.0.99"

SYST:CONF "WirelessIPAddress = 192.168.0.99"

IPDNS/WirelessIPDNS

DNS servers

Parameter syntax: IPDNS1, WirelessIPDNS1 and IPDNS2, WirelessIPDNS2

Possible values: IP address (four numbers, dot-separated)

Default value (RST condition): 8.8.8.8

Description

DNS server(s) IP addresses for Ethernet interface when static IP address mode is enabled in IPMode parameter. When DHCP mode is enabled, these settings are assigned by a DHCP server in network and can be read back with SYST:CONF? query)

1st nameserver IP address for Wireless interface (with DHCP, configured address can be read back)

Example

SYST:CONF "IPDNS1 = 8.8.8.8; IPDNS2 = 1.1.1.1"

SYST:CONF "WirelessIPDNS1 = 8.8.8.8; WirelessIPDNS2 = 1.1.1.1"

IPGateway/WirelessIPGateway

Default gateway.

Parameter syntax: IPGateway, WirelessIPGateway

Possible values: IP address (four numbers, dot-separated)

Default value (RST condition): 192.168.0.1

Description

Gateway IP for Ethernet interface when static IP address mode is enabled in IPMode parameter. When DHCP mode is enabled, this setting is assigned by a DHCP server in network and can be read back with SYST:CONF? query)

Gateway IP address for Wireless interface (with DHCP, configured address can be read back)

Example

SYST:CONF "IPGateway = 192.168.0.1"

SYST:CONF "WirelessIPGateway = 192.168.0.1"

IPMode/WirelessIPNetmask

Select whether to configure IP address automatically from DHCP server or manually

Parameter syntax: IPMode, WirelessIPMode

Possible values: DHCP, Static

Default value (RST condition): DHCP

Description

IP configuration mode for Ethernet interface

IP netmask for Wireless interface (with DHCP, configured netmask can be read back)

DHCP- IP settings are aquired via DHCP

Static- Static IP configuration. When this mode is selected you should also configure IPAddress and IPNetmask, IPGateway, IPDNS1 (and optionally IPDNS2) parameters.

Example

SYST:CONF "IPMode = DHCP"

SYST:CONF "WirelessIPMode = DHCP"

IPNetmask/WirelessIPNetmask

IP netmask

Parameter syntax: IPNetmask, WirelessIPNetmask

Possible values: IP mask (four numbers, dot-separated)

Default value (RST condition): 255.255.255.0

Description

IP netmask for Ethernet interface when static IP address mode is enabled in IPMode parameter. When DHCP mode is enabled, this setting is assigned by a DHCP server in network and can be read back with SYST:CONF? query)

IP netmask for Wireless interface (with DHCP, configured netmask can be read back)

Example

SYST:CONF "IPNetmask = 255.255.255.0"

SYST:CONF "WirelessIPNetmask = 255.255.255.0"

Other configuration and control commands

:SYSTem:ERRor

Read the Error/Event Queue

You read the error queue with the :SYSTem:ERRor? query.

Example:

SEND → :SYST:ERR?

READ ← -220,"Parameter error;Wrong enum value '25x' for setting 'AttenuationA'"

The query returns the error number followed by the error description.

If more than one error occurred, the query will return the error that occurred first. When you read an error, you will also remove it from the queue. You can read the next error by repeating the query.

When you have read all errors, the queue is empty, and the :SYSTem:ERRor? query will return:

0, "No error"

When errors occur and you do not read these errors, the Error Queue may overflow. Then the instrument will overwrite the last error in the queue with:

-350, "Queue overflow"

If more errors occur they will be discarded.

It is a good practice to check for errors after instrument configuration and before starting a measurement.

:DISPlay:ENABle

Display results on-screen On/Off

This command switches displaying measurement results on-screen on or off. Switching off is useful to boost fetching speed for block measurements. If switched off, the user will see a lock screen that can be unlocked by tapping a button, unless the device is in Remote Locked state.

*RST condition: 1

:ROSCillator:STATE

Query reference clocks (time base) statuses.

Query syntax

:ROSCillator:STATE?

Query response format:

<used_ref_status>, <int_ref_status>, <ext_ref_status>

Where

<used_ref_status> is one of INT, EXT or FAIL

<int_ref_status> is one of OK, FAIL

<ext_ref_status> if one of 1MHz, 5MHz, 10MHz, FAIL

Description

This query provides extensive information about currently used reference clocks and the state of internal and external reference clock signals. The response contains 3 fields separated by commas.

First field indicates which time base is currently in use: internal (INT), external (EXT) or none (FAIL).

Second field indicates status of internal time base reference: OK or FAIL.

Third field indicates whether external reference signal is connected (1MHz, 5MHz or 10MHz) or not (FAIL).

Example:

SEND → :ROSC:STATE?

READ ← EXT, INT OK, EXT 10MHz

Acquisition of measurement data

:FETCh[:SCALar]

Fetch one result

Query syntax

:FETCh[:SCALar]? [<series name>]

where <series names> in measurement function dependent series

Query response format

The format of the returned data is determined by the format commands :FORMAT:TINF and :FORMAT:DATA. See description below.

Description

The fetch query retrieves one measurement result for the given series name without making new measurements. Fetch does not work unless a measurement has been made by the :INITiate command. Series name argument is optional. If ommited, the command will default to first series for current measurement. If the counter has made an array of measurements, the query fetches the first measuring results first. The second query fetches the second result and so on. When the last measuring result has been fetched, the query returns empty string.

Measuring result can be fetched as long as the result is valid, i.e. until the following occurs:

– *RST is received.

– an :INITiate command is executed

– any reconfiguration is done.

The format of the returned data is determined by the format commands :FORMAT:TINF and :FORMAT:DATA:

	:FORMAT:DATA ASCii	:FORMAT:DATA REAL	:FORMAT:DATA PACKED
:FORMAT:TINF OFF	<Val>,<Val>,<Val>…	#18<Val>,#18<Val>,#18<Val>…	#280<Val><Val><Val>…
:FORMAT:TINF ON	<Val>,<TS>,<Val>,<TS>,<Val>,<TS>	#18<Val>,#18<TS>,#18<Val>,#18<TS>,#18<Val>,#18<TS>…	#6000160<Val><TS><Val><TS><Val><TS>….

Val = measurement value (double-precision floating-point format according to IEEE-754 in REAL and PACKed)

TS = timestamp value (double-precision floating-point format according to IEEE-754 in REAL, and 64-bit integer representing the number of picoseconds in PACKed)

#18 and #3160 - are binary data headers. First digit after “#” represent the number of subsequent digits. Those digits specify the size of a binary data (in bytes) that follow the header. For example, in REAL format in the header #18 "1" indicates that there is one more digit to read after “#”. “8” indicates that there will be 8 bytes of binary samples. In PACKED format the header #6000160 shows that there are 6 more digits after '#'. 000160 indicates that there will be 160 bytes of binary data.

In some situations, the instrument may not be able to provide valid results because of a measured value exceeds expected range (for example signal has too big amplitude or frequency is too high). In such situations the samples returned by :FETCh[:SCALar] and :FETCh:ARRay will have special ‘infinity’ value. In ASCII format it will be inf string, and for REAL and PACKED formats it will be bit pattern corresponding to infinity according to IEEE 754.

:FETCh:ARRay

Fetch an array of results

Query syntax

:FETCh:ARRay <fetch array size>, [<series name>]

where <fetch array size> is either an integer number or MAX keyword and <series name> is series name.

Query response format

The format of the returned data is determined by the format commands :FORMat and :FORMat:FIXed. See :FETCh[:SCALar] for formats description.

Description

:FETCh:ARRay? query differs from the :FETCh? query by fetching several measuring results at once.

<fetch array size> must be positive integer value or MAX keyword. Data samples in response are present in the order they were created by the measurement core of the instrument (sorted by time, earliest sample is first). Maximum allowed array size for a single fetch is 1000000. Samples are fetched in FIFO-manner. For example, when the instrument has made a measurement and an array of measurements is available for input 'A' then :FETCh:ARRay? 10, A fetches the first 10 measuring results from the output queue. The second :FETCh:ARRay? 10, A fetches results 11 to 20, and so on. When the last measuring result has been fetched, :FETCh:ARRay? 10, A returns empty string.

:FORMat[:DATA]

Specifies format of the data samples that are returned in response to FETCH:SCALAR? and FETCH:ARRAY? queries.

Command syntax

:FORMat[:DATA] <format>

where <format> is one of ASCii, REAL or PACKed

Query syntax

:FORMat[:DATA]?

Query response

ASCII, REAL or PACKED

Default value: ASCII

Description

ASCii: Returned data samples are represented as floating point numbers in text, separated by comma (for FETCH:ARRAY? query).

REAL: Returned data samples are represented as binary data with “#18” header. Each sample or timestamp consists of 8 bytes.

PACKed: See REAL.

For more details, see :FETCh[:SCALar] query description.

:FORMat:TINFormation

Specifies whether timestamps are included in data samples that are returned in response to FETCH:SCALAR? and FETCH:ARRAY? queries.

Command syntax

:FORMat:TINFormation <boolean>

where <boolean> is one of 1, 0, ON, OFF

1 or ON enable timestamping

0 or OFF disable timestamping

Default value: OFF

Description

This command turns on/off the time stamping of measurements. The setting of this command will affect the output format of FETCh queries.

For more details, see :FETCh[:SCALar] query description.

Connection to the instrument using SCPI

For controlling the instrument over Ethernet connections, HiSLIP (High-Speed LAN Instrument Protocol) is used. Simplest way to communicate with the instrument from a PC is to make use of VISA software, for example NI VISA. For connecting to the instrument, a connection resource string in the following form will be required:

TCPIP::<IP address>::hislip0::INSTR

Replace <IP address> with IPv4 address of the instrument, for example:

TCPIP::192.168.0.25::hislip0::INSTR

IP address of the instrument can can checked in Settings → User Options → Network page in device’s on-screen interface.

Example of a simple measurement

Send this commands to the instrument to make 200 period measurements of the signal on the input D, averaged over 10 ms intervals with auto-trigger and send results. (Signal is assumed to be present on input D).

Queries (commands with '?' sign) assume reading response from the instrument.

*RST; *CLS SYST:CONF "Function=Period Average D; SampleCount=200; SampleInterval=10ms; VoltageMode=VeryFast" :INIT *OPC? FETC:ARR? MAX

Instrument programming in Python environment

Installing prerequisites

Download and install NI VISA software: NI-VISA Download

Download and install latest Python 3 version: Download Python

Checking Python installation

Open command prompt:

on Windows: press Win+R, type cmd, press Enter. You will see a window where you can type commands:

In command prompt type

python --version

python3 --version

followed by Enter to check if python is correctly installed. You should get response indicating installed python version, like this:

Python 3.11.4

On Windows, if Microsoft Store is open when you execute “python” command or the command simply gives no response:

On Windows 11 go to Start Menu → Settings → Apps → Advanced app settings → App execution aliases and disable “python” and “python3” aliases.

On Windows 10 open Start Menu → Settings (“Gear” icon) → Applications → Applications and functions → Link “Application execution aliases”. Disable “python” and “python3” items.

PyVISA library installation

Open source PyVISA library can be used for interaction with NI VISA software which, in turn, provides functionality required to support communication with measurement instruments using protocols such as HiSLIP.

To install PyVisa library open command prompt and type:

pip install pyvisa

If you receive error message saying “'pip' is not recognized as an internal or external command, operable program or batch file.“, then ensure that Python is correctly installed.

Check if communication with Pendulum CNT-104S device is possible from python (at the very basic level):

Ensure your instrument is connected to the network.
Start Python in interactive mode by typing in command prompt:

python

In python command prompt type the following lines replacing 192.168.0.25 with the actual IP address of your instrument (can be checked in Settings → User options → Network → Ethernet IP address):

import pyvisa as visa
rm = visa.ResourceManager()
instr = rm.open_resource('TCPIP::192.168.0.25::hislip0::INSTR')
instr.query('*IDN?')

The last line executes “*IDN?” query which asks the instrument for identification information. You should get response from the instrument like this:

'Pendulum, CNT-104S, 607017, v1.2.0 2023-07-13\n'

Type the following to disconnect from the instrument and exit python:

instr.close() quit()

Examples

More complex scenarios imply using Python in non-interactive mode.

Here is an example showing very basic usage of python programming language to control the instrument.

#!/usr/bin/env python

# REPLACE WITH THE IP ADDRESS OR YOUR INSTRUMENT!
# (See Settings -> Settings -> User options -> Network -> Ethernet IP address)
INSTRUMENT_IP = '192.168.0.25'

import pyvisa as visa

rm = visa.ResourceManager()

def example(resource_str):

    instr = rm.open_resource(resource_str)  # Connect to the instrument
    instr.timeout = 5000  # VISA I/O operations timeout, in milliseconds

    idn = instr.query('*IDN?')  # Send '*IDN?' and read response.
    print('Running example 1 with {} at {}'.format(idn.strip(), resource_str))
    print('In this example frequency measurement is performed on input A')

    instr.write('*RST;*CLS')  # Reset to default settings, clear error and message queues.
    # Configure the measurement: simple frequency measurement, with timeout.
    # (Pay attention to double and single quotes)
    instr.write(':SYSTEM:CONFIGURE "Function=Frequency A; SampleCount=10; SampleInterval=0.01; '
                'Timeout=On; TimeoutTime=1.0"')
    # It's a good practice to check for errors.
    err = instr.query(':SYST:ERR?')
    if err.strip() != '0,"No error"':
        raise Exception('Error configuring measurement: {}'.format(err))

    instr.write(':INIT')

    # Waiting (in a blocking manner) for measurement completion.
    # *OPC? query responds back only when all pending operations (measurement in this case) are completed.
    # Measurement will be complete when all requested samples are collected or if timeout occurs.
    instr.query('*OPC?')  # No need to use response here, because it is always '1' by SCPI standard.

    data_str = instr.query(':FETCH:ARRAY? MAX, A')  # Will return a string of comma-separated numbers
    data_str = data_str.strip()  # to remove \n at the end
    if len(data_str) > 0:
        data = list(map(float, data_str.split(',')))  # Convert the string to python array
    else:
        data = []

    # Display measurement results
    print('Results: {}'.format(data if data else 'no data (signal not connected?)'))
    instr.close()

if __name__ == '__main__':
    resource_str = 'TCPIP::{}::hislip0::INSTR'.format(INSTRUMENT_IP)
    try:
        example(resource_str)
    except visa.VisaIOError as e:
        print('Error occurred: {}'.format(e))