Tabor Electronics 5064, Руководство пользователя

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QAM:DATA<qam_data>
Description
Loads the data stream that will cause the 2074 to hop from vector to vector. Data format is a string of "0
’s"
and "1
’s" which define when the output generates the various vectors. The size of the data word depends
on the QAM type. For 16QAM there are only four bits and for 256QAM there are 8 bits. Note that if you
intend to program marker position, you must do it before you load the PSK data list.
Below you can see how a 16QAM data table is constructed. The 16QAM data table sample below shows a
list of 10 shifts. The 2074 will step through this list, outputting the various vectors in a sequence as defined
by the data list.
Sample 16QAM Data Array
0000 0100 1010 0111 1111 0001 0010 0111 0101 1111
Parameters
Name Type Description
<qam_data> ASCII Block of ASCII data that contains information for the
generator when to step from one vector setting to
another.
QAM:MARKer<index>(?)
Description
Programs where on the data stream the 2074 will generate a pulse, designated as QAM marker, or index
point. The marker pulse is generated at the SYNC output connector. Note that if you intend to program
marker position, you must do it before you load the QAM data list. The QAM:MARK command is common to
all QAM modulation types.
Parameters
Name Range Type Default Description
<index> 1 to
4000 Numeric
(integer only) 1
Programs a marker pulse at an index bit position.
Response
The 2074 will return the present marker position.