MDO3000 Programmer Manual.pdf - 第134页

Command Groups T able 2-47: Digital Collection: 8 Byte Data (cont.) Bit Number Description 48 CH1 transition state M SB 47 D 1 5t r a n s i t i o ns t a t eM S B ... 33 D1 transition state MSB 32 D0 transition state MSB …

Command Groups

In this case, th

e Digital Collection data returned will be 32-bit packed integers,

where each point is represented as follows. Note that the trigger state bit described

below is only available when ACQuire:MAGnivu is 1 (on).

Table 2-46: Digital Collection: 4 Byte Data

Bit number Description

31– 22 not used

21 trigger state

not used (always 1)

CH4 digital state

CH3 digital state

CH2 digital state

CH1 digital state

15 D15 state

...

1 D1 state

0 D0 state

8ByteData. When the data width is set to 8 bytes, the Digital Collection

represents

the transition state information for digital channels D0 – D15 and

the digital representations of analog Channels 1 – 4.

The "transition state" refers to MSB and LSB bits which together represent the

state of the digital channel during the sampling period, as fol

lows:

MSB LSB Transition/State

0 0 Low

01High

Single transition

1 1 Multiple transitions

If the width speciﬁed using the DATa:WIDth command is 8 bytes, the Digital

Collection data returned will be 64-bit packed integers, where each point is

represented as follows:

Table 2-47: Digital Collection: 8 Byte Data

Bit Number Description

63 — 52 not used

CH4 trans ition state MS B

CH3 trans ition state MS B

CH2 trans ition state MS B

MDO4000/B/C, MSO/DPO4000B and MDO3000 Series Oscilloscopes Programmer Manual 2-103

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