MDO3000 Programmer Manual.pdf - 第135页

Command Groups Ta b l e 2 - 4 8 : W a v eform T ransfer Commands Command Description CURV e The CURV e command transfers the w aveform data poi nts TO the oscilloscope’s internal reference memory location (REF1–4), which…

Command Groups

Table 2-47: Digital Collection: 8 Byte Data (cont.)

Bit Number Description

CH1 transition state M SB

D15transitionstateMSB

...

D1 transition state MSB

D0 transition state MSB

31 — 20 not used

CH4 transition state LSB

CH3 transition state LSB

CH2 transition state LSB

CH1 transition state LSB

D15 transition state LS B

...

D1 transition state LSB

D0 transition state LSB

For example, to ﬁnd the transition state of the digital channel D0, set

DATa:SOUrce to

DIGITAL and DATa:WIDth to 8. Look at bits 0 and 32 in the

ata returned by the

CURVe? or WAVFrm? queries, where bit 0 is the transition

state LSB and bit 32 is the transition state MSB for D0.

2-104 MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual

Command Groups

Table 2-48: Wav

eform Transfer Commands

Command

Description

CURVe The CURVe command transfers the w aveform data points TO the oscilloscope’s internal

reference memory location (REF1–4), which is speciﬁed by the

DATa:DESTination

command. The

CURVe? query transfers data F ROM the oscilloscope; the source waveform

is speciﬁed by the

DATa:SOUrce command. The ﬁrst and last data points are speciﬁed by

the

DATa:STARt and DATa:STOP commands.

Associated

with each waveform transferred using the

CURVe command or query is a

waveform preamble that provides the data format, scale and associated information needed

to interpret the waveform data points. The preamble information for waveforms sent TO the

oscillosco

pe is speciﬁed using the

WFMInpre commands. The preamble information for

waveforms transferred FROM the oscilloscope is speciﬁed or queried using the

WFMOutpre

commands. If the waveform is not displayed, the query form generates an error.

The

CURVe c

ommand and

CURVe? query transfer waveform data in ASCII or binary

format. ASCII data is sent as a comma-separated list of decimal values. Binary data is sent

with the IEEE488.2 binary block header immediately followed by the binary d ata.

DATa

These commands specify the format and location of waveform data that is transferred

using the

CURVe command, or return the format and location of the w aveform data that

is transferred with the CURVe? query. You can use the

INIT argument to reset all of

the

DATa parameters to default values. (Note that the *RST and FACtory commands

do not re

set the

DATa parameters.) You can use the SNap argument to automatically

set the

DATa:STARt and DATa:STOP values to the starting and stopping point of the

waveform cursors (if on). Note that setting

DATa:STARt and DATa:STOP automatically

sets

WFM

Outpre:NR_Pt.

DATa:D

ESTination

This co

mmand speciﬁes the reference memory location (REF1–4) for storing waveform data

transferred into the oscilloscope using the CURVe command.

DATa:ENCdg This command speciﬁes the encoding format for outgoing waveform data. This command is

equivalent to setting WFMOutpre:ENCdg, WFMOutpre:BN_Fmt, and WFMOutpre:BYT_Or.

Setti

ng the

DATa:ENGdg value causes the corresponding WFMOutpre values to be

updated.

DATa:SOUrce This command speciﬁes the s ource waveform to be transferred from the oscilloscope

using the

CURVe? query. The valid waveform sources are CH1-CH4, MATH,

REF1

-REF4, D0-D15, DIGital, RF_AMPlitude, RF_FREQuency,

RF_PHASe, RF_NORMal, RF_AVErage, R F_MAXHold, and RF_MINHold.

Setting DATa:SOUrce automatically constrains the fo llowing to valid values for the

spe

ciﬁed source waveform:

WFMOutpre:BYT_Nr, W FMOutpre:BIT_Nr and

WFMOutpre:BN_Fmt.

NOTE. The RF time domain traces, RF_AMPlitude, RF_FREQuency and

RF_PHASe, are only available on the MDO4000/B/C series models.

DATa:STARt This command speciﬁes the starting data point for incoming or outgoing waveform transfer

ing the

CURVe command or query. (Use DATa:STOP to specify the ending data point.)

You can set the

DATa:STARt and DATa:STOP values automatically to the starting

and stopping points of the waveform cursors, if on, using

DATa SNap. Note that setting

ATa:STARt

and DATa: STOP automatically sets WFMOutpre:NR_Pt.

ATa:STOP

his command speciﬁes the ﬁnal data point that will be transferred when using the CURVe

command or query for incoming or outgoing waveform transfer. (Use

DATa:STARt to

specify the starting data point.)

MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual 2-105

Command Groups

Table 2-48: Waveform Transfer Commands (cont.)

Command

Description

DATa:WIDth

This command speciﬁes the width, in bytes per point, for waveform data transferred from the

scope via the

CURVe? query. (This command is synonymous with WFMOut pre:BYT_Nr

.) When the source isCH1-CH4, REF1-REF4, MATH, D0-D15, RF_AMPlitude,

RF_FREQuency and RF_PHASe,

the default width is 1 byte. When the source is

RF_NORMal, RF_AVERage, RF_MAXHold, or RF_MIN Hold, the default width

is 4 bytes.

NOTE. The RF time domain traces, RF_AMPlitude, RF_FREQuency and

RF_PHASe, are only available on the MDO4000/B/C series models.

WA VFrm? This query returns the waveform preamble and the waveform data for the source waveform

speciﬁed by the

DATa:SOUrce command. This command is equivalent to sending both

WFMOutpre? and CURVe?, with the additional provision that the r esponse to WAVFrm?

is guaranteed to provide a synchronized preamble and curve.

WFMInpre? Returns the waveform formatting and scaling speciﬁcations to be applied to the next

incoming

CURVe command data.

WFMInpre:BIT_Nr

This command speci ﬁes the number of bits per data point in the waveform data to be sent

to the oscilloscope using the

CURVe command. Changing this value also changes the

value of WFMInpre:BYT_Nr.

WFMInpre:BN_Fmt

This command speciﬁes the format of the data for outgoing waveforms when

WFMInpre:ENCdg is set to BINary. The format can either be RI (signed integer), RP

(positive integer) or FP (ﬂoating point).

WFMInpre:BYT_Nr

This command speciﬁ es the number of bytes per data point in the waveform data to be

sent to the oscilloscope using the

CURVe command. Changing this value also changes

the value of WFMInpre:BIT_Nr.

WFMInpre:BYT_Or This command speciﬁes which byte of incoming binary waveform data is transmitted ﬁrst

(the byte order). T he byte order can either be MSB (most signiﬁcant byte ﬁrst) or LSB (least

signiﬁcant byte ﬁrst, also known as IBM format). This speciﬁcation only has meaning when

WFMInpre:ENCdg is set to BINary and WFMInpre:BYT_Nr is 2.

WFMInpre:CENTERFREQuency This command speciﬁes the center frequency of the incoming RF trace (waveform), in hertz.

The center frequency is a precise frequency at the center of the frequency domain display.

In many applications, it is a carrier frequency.

WFMInpre:DOMain This command speciﬁes whether the information being sent to a reference location should

be treated as integer (time domain) information, or ﬂoating point (frequency domain)

information, for the purposes of storing the data internally. The default is

TIMe.This

parameter should be set before using the

CURVe com mand to transfer a waveform from a

PC to an internal reference location.

WFMInpre:ENCdg This command speciﬁes the type of encoding of the incoming waveform data to be sent to

the oscilloscope using the

CURVe command. Supported types are BINary and ASCii.

WFMInpre:NR_Pt

This command speciﬁes the number of data points that are in the incoming waveform record

to be sent to the oscilloscope using the

CURVe command.

WFMInpre:PT_Fmt

This command speciﬁes the format of the data points to be sent to the oscilloscope using the

CURVE command. This can be Y for YT format, or EN V for envelope format (min/max pairs).

Regardless of the argument used, the scale, offset, and so on are interpreted similarly.

When ENV is used, waveform data is interpreted as min-max pairs (the minimum value

precedes the maximum for each pair); when Y is used, it is interpreted over a single point.

2-106 MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual