Tektronix MSO54, Руководство программиста

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Appendix D: Waveform Transfer (WFMOutpre and CURVe Query) Examples
WFMOutpre? Query results Explanation
WFMOUTPRE:BYT_NR 8
This value speci fi es the number of bytes per data point in the waveform data. To change
this value automatically, use the WFMOutpre:BYT_Nr command. Note that changing this
value automatically changes the
BIT_NR
value accordingly. (This value can also be set
using the DATa:WIDth command.)
BIT_NR 64
This value speci fi es the number of bits per data point in the waveform data. To change this
value, use the WFMOutpre:BIT_Nr command. Note that changing this value automatically
changes the
BYT_NR
value accordingly.
ENCDG ASCII
This value speci fi es the encoding of the waveform data. To change this value (the
other possibility is BINARY), use the WFMOutpre:ENCdg command. (This value can
also be set using the DATa:ENCdg command, which provides the ability to set the
WFMOutpre:ENCdg, WFMOutpre:BN_Fmt,
: and
WFMOutpre:BYT_Or
values
using a single command.)
BN_FMT RI
This value speci fi es the binary format, which in this case is RI (signed integer). To change
this value (the other possibility is RP or positive integer), use the WFMOutpre:BN_Fmt
command. Note: this fi eld is not applicable for ASCii encoding.
BYT_OR MSB
This value speci fi es the byte order for the BINARY encoding, which in this case is MSB
(most signi fi cant byte fi rst, also known as IBM format). To change this value to LSB, use the
WFMOutpre:BYT_Or command. Note: this fi eld is not applicable for ASCii encoding.
WFID "Digital, unknown
coupling, 100.0us/div,
10000 points, Digital
mode"
This quoted string represents information about the source waveform that would be returned
by a.
WFMOutpre:WFId?
query. It cannot be changed.
NR_PT 25
This value indicates the number of data points in the waveform record. (If you would like to
determine only this value, use the
WFMOutpre:NR_Pt? query.) Note: this value is typically
equal to the full record length, but you also have the option to transfer only a portion of the
record length by using the
DATa:STARt and DATa:STOP commands.
PT_FMT Y
This value indicates the format of the data points in the waveform record. In this case,
the value represents YT format. This is query only – the returned values can be Y for YT
format or ENV for envelope format (min/max pairs). (If you would like to determine only this
value, use the
WFMOutpre:PT_Fmt? query.)
PT_ORDER LINEAR
This value is always
LINear
.
XUNIT "s"
This value indicates the units of the x-axis of the waveform record. This is determined by the
horizontal settings for the waveform source. Typically, this value is “s”, representing seconds.
When using the math waveform as a source, the value can be “s” or “Hz”. This is query only.
(If you would like to determine only this value, use the
WFMOutpre:XUNit? query.)
XINCR 1.2121E-9
This value indicates the time, in seconds, or frequency, in hertz, between data points in the
waveform record. This is query only. (If you would like to determine only this value, use
the
WFMOutpre:XINcr? query.)
XZER0 -6.0606E-6
This value indicates the time, in seconds, or frequency, in hertz, of the fi rst data point in the
waveform record. This time or frequency is relative to the time of the trigger, which is always
0. So, this XZEro time or frequency can be negative. This is query only. (If you would like to
determine only this value, use the
WFMOutpre:XZEro? query.)
PT_OFF 0
This is a query provided only for compatibility with other Tektronix oscilloscopes. The
returned value is always 0. (If you would like to determine only this value, use the
WFMOutpre:PT_Off? query.)
D-14 MSO54, MSO56, MSO58, MSO58LP Programmer