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Command Groups T able 2-43: Video Picture Commands (cont.) Command Description VIDPic:LOCation:OFFSet Sets (or queries) the video picture line-to-line offset. This is the amount of additional delay time to add between li…

Command Groups

Table 2-42: Vertical Commands (cont.)

Command Description

REF<x>:HORizontal:SCAle This command speciﬁes the horizontal scale for a reference w aveform

REF<x>:LABel

This command speciﬁes the speciﬁed reference waveform label

REF<x>:TIMe? Returns the time that a reference waveform was stored

REF<x>:VERTical:POSition This command speciﬁes the vertical position of the speciﬁed reference

waveform

REF<x>:VERTical:SCAle This command speciﬁes the reference waveform vertical scale in vertical

units/div

SELect? Returns information on which waveforms are on or off and which waveform

is selected.

SELect:{BUS<x>|B<x>} Turnsonoroffthespeciﬁed bus waveform or returns whether the speciﬁed

bus channel is on or off

SELect:CH<x> Turnsonoroffthespeciﬁed waveform or returns whether the speciﬁed

channel is on or off

SELect:CONTROl This command speciﬁes the waveform that is selected as the implied recipient

of channel-related commands

SELect:DAll This command turns on or off all digital channels (D0 — D15).

SELect:D<x> Turns on the display of digital channel <x> and resets the acquisition

SELect{:MATH|:MATH1} Turns on or off the math waveform or returns whether the math waveform is

on or off

SELect:REF<x> Turnsonoroffthespeciﬁed reference waveform or returns whether the

speciﬁed reference waveform is on or off

VideoPictureCommandGroup

The video picture features as well as triggering on a video signal are included

standard with the MDO3000 series models. These features require the DPO4VID

application module for use with MSO/DPO4000B and the MDO4000/B/C models.

Use the video picture commands for video picture functionality.

Table 2-43: Video Picture Commands

Command Description

VIDPic:AUTOContrast Sets (or queries) the video picture automatic contrast state.

VIDPic:AUTOContrast:UPDATERate Sets (or queries) the number of frames between automatic contrast updates

VIDPic:BRIGHTNess Sets (or queries) the video picture brightness level as an integer percentage.

VIDPic:CONTRast Sets (or queries) the video picture contrast level as an integer percentage.

VIDPic:DISplay Sets (or queries) the video picture display state.

VIDPic:FRAMETYPe

Sets (or queries) the video picture frame type (O DD, EVEN or INTERLAced).

VIDPic:LOCation:HEIght Sets (or queries) the video picture height, in rows.

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Command Groups

Table 2-43: Video Picture Commands (cont.)

Command Description

VIDPic:LOCation:OFFSet Sets (or queries) the video picture line-to-line offset. This is the amount of

additional delay time to add between lines of the video picture.

VIDPic:LOCation:STARt:LINE Sets (or queries) the video picture starting l ine number.

VIDPic:LOCation:STARt:PIXel Sets (or queries) the video picture starting pixel in each line

VIDPic:LOCation:WIDth Sets (or queries) the video picture width, in columns.

VIDPic:LOCation:X Sets (or queries) the video picture X origin location, in columns.

VIDPic:LOCation:Y Sets (or queries) the video picture Y origin location, in rows.

VIDPic:SOUrce Sets (or queries) the channel to use for the video picture source waveform.

VIDPic:STANdard Sets (or queries) which video picture standard to use (either NTSC or PAL).

Wa veform Transfer Command Group

(See Table 2-48.)

The

CURVe and other commands and queries in the Waveform Transfer Command

Group are used to transfer waveform data points to and from the oscilloscope.

Thewaveformdatapointsareacollectionofvaluesthatrepresenttheamplitude

of the waveform samples. One data value usually represents one data point inthe

veform record. Only one waveform can be transferred at a time.

Each waveform you transfer has an associated waveform preamble, which

ontains information such as data format, horizontal scale, vertical scale, and the

other settings in effect when the waveform was created. When you transfer a

waveform, you need to specify at least some of the general and preamble settings

(using the

DATa, WF MInpre or WFMOutpre commands) before you specify the

raw data point information (using the

CURVe command or query.)

Waveform data can be transferred to or from the oscilloscope using the Ethernet

or USBTMC interfaces in binary or ASCII format. Binary data transfer is

considerably more efﬁcient than ASCII data transfer. Binary data is transferred to

and from the oscilloscope using the IEEE488.2 arbitrary block format (7.7.6 of

the IEEE488.2 spec) which we refer to in this document as “binary block format”.

A binary block is represented as:

#N<N-Digits><binary data>

Where:

The “#” is the arbitrary block token.

N is a single hexadecimal digit specifying how many decimal digits

immediately follow.

<N-Digits> is a decimal number N digits long, that speciﬁes the number of

binary data bytes to follow.

MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual 2-95

Command Groups

<binary data> i

s the binary data which should be exactly N-Digits bytes in

length.

NOTE. Ifyouwouldliketosaveorrecallawaveformtoorfromaﬁle, use the

SAVe:WAVEform and RECAll:WAVEform commands.

Transferring a Waveform

from an Oscilloscope to a

Computer

Use the DATa commands and WFMOutpre commands to specify the attributes of

the waveform being transferred from the oscilloscope. You must, at a minimum,

specify the waveform source (using the

DATa:SOUrce command) and data format

(using the

DATa:ENCdg and DATa:WIDth commands).

Then, use the

WFMOutpre? query, which provides the context needed to interpret

the waveform data points. Finally, use the

CURVE? query to transfer the waveform

data points. (You can also use the

WAVFrm? query, which concatenates the

WFMOutpre? and CURVe? queries. )

NOTE. In order to guarantee that the waveform data returned from

CURVE?

queries of multiple waveforms are correlated to the same acquisition, you

should use single sequence acquisition mode to acquire the waveform data

from a single acquisition. Single sequence acquisition mode is enabled using

ACQuire:STOPAfter

SEQuence

NOTE. The

WFMOutpre:BYT _Nr

and

WFMOutpre:BIT _Nr

settings are

directly related; setting one causes the other to be set accordingly. For

example,

WFMOutpre:BY T_Nr 2

causes

WFMOutpre_B IT_Nr

to be set to

16 (2 * 8 bits/byte). Similarly, setting

WFMOutpre: BIT_Nr

to 16 causes

WFMOutpre: BYT_Nr

to be set to 2.

Following is an example command sequence that illustrates how to transfer

waveform data from the oscilloscope to the computer.

In this case, let’s say you’d like to transfer 10,000 points from channel 1, in ASCii

format with 1 byte per point, to your computer program.

Table 2-44: Example Command Sequence for Transferring Waveform Data from Oscilloscope to Computer

Item Description

:DATa:SOUrce CH1 Sets the source waveform to be transferred to Channel 1.

:DATa:STARt 1 This, along with DATa:STOP, speciﬁes the portion of the w aveform record that will

be transferred .

:DATa:STOP 10000

:DATa:ENCdg ASCIi Sets the data format to ASCII. (This command replaces WFMOutpre:ENCdg,

WFMOutpre:BN_Fmt

and WFMOutp re:BYT_Or with a single command.)

:DATa:WIDth 1

Sets 1 byte per point (same as

WFMOutpre:BYT_Nr).

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