Tabor Electronics 5251, User Manual

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4
Remote Programming Reference
Modulated Waveforms Control Commands
4-55
FSK:FREQuency:MARKer<index>(?)
Description
Programs where on the data stream the 5251 will generate a pulse, designated as FSK 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 FSK data list.
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 5251 will return the present marker position.
FSK:DATA<fsk_data>
Description
Loads the data stream that will cause the 5251 to hop from carrier to shifted frequency and visa versa. Data
format is a string of "0" and "1" which define when the output generates carrier frequency and when it shifts
frequency to the FSK value. "0" defines carrier frequency,"1" defines shifted frequency. Note that if you
intend to program marker position, you must do it before you load the FSK data list.
Below you can see how an FSK data table is constructed. The sample below shows a list of 10 shifts. The
5251 will step through this list, outputting either carrier or shifted frequencies, depending on the data list:
Zero will generate carrier frequency and One will generate shifted frequency. Note that the waveform is
always sinewave and that the last cycle is always completed.
Sample FSK Data Array
0 1 1 1 0 1 0 0 0 1
Parameters
Name Type Description
<fsk_data> ASCII Block of ASCII data that contains information for the
generator when to shift from carrier to shifted
frequency and visa versa.