Tektronix DSA8300, Руководство программиста

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Command Groups
Waveform Transfer Command Group
Use the commands in the Waveform Transfer Command Group to transfer
waveform data points to and from the instrument. Waveform data points are a
collection of values that de
fi ne a waveform. One data value usually represents
one data point in the waveform record. When working with envelope waveforms,
each data value is either the minimum or the maximum of a min/max pair.
Before you transfer waveform data, you must specify the data format, record
length, and waveform source.
Data Formats
Acquired waveform data uses 19 or more bits to represent each data point. The
number of bits used depends on the acquisition mode speci
fi ed when you acquired
the data. Data acquired in SAMple or ENVElope mode uses 19 bits per waveform
data point. Data acquired in AVERage mode uses up to 24 bits per point.
The instrument can transfer waveform data in either ASCII or binary format. You
specify the format with the DATa:ENCdg command. The instrument uses signed,
4 byte integers and
fl oating point values; it does not support unsigned values.
ASCII data is represented by signed integer or fl oating point values. An example
of an ASCII waveform data string may look like this:
:CURVE -509476864,-512163840,-511115264,-510918656,
-516161536,-484179968,-117112832,207093760,
322437120,351600640,409206784,468451328,
482934784,490668032,495517696,432668672,
482148352,483655680,493617152,495321088,
499843072,493420544,488964096,497221632,
…
ASCII will produce more readable and more easily formatted output than that
produced by binary format. However, ASCII may require more bytes to send the
same values than it does with binary. This may reduce transmission speeds.
Binary data can be represented by signed integer or fl oating-point values. The
de fi ned binary formats specify the order in which the bytes are transferred. The
following are the four binary formats:
RIBinary speci fi es signed integer data-point representation with the most
signi fi cant byte transferred fi rst.
SRIBinary is the same as RIBinary except that the byte order is reversed;
the least signi fi cant byte is transferred fi rst. This format is useful when
transferring data to IBM-compatible PCs.
FPBinary speci fi es fl oating-point data-point representation with the most
signi fi cant byte transferred fi rst.
SFPBinary is the same as RFBinary except that the byte order is reversed;
the least signi fi cant byte is transferred fi rst. This format is useful when
transferring data to IBM-compatible PCs.
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