Racal Instruments 3156B, Руководство пользователя

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3156B User Manual
Programming Reference 5-118 Racal Instrument © 2005
model type is used, this will be used to differentiate
between them. Note that the initialize function may be
used to associate multiple instrument handles with a
single instrument.
FSKzeroFrequency
ViReal64
Selects the frequency where the 3156B will remain when
the controlling bit is zero.
Valid range: 0.01 to 25e6 (Hz)
Default: 1e6
Return Values
Displays the return status of the function call. If the function was successful, it will return a status of
VI_SUCCESS, otherwise it will return an error code. Passing the error code into the function
"ri3156B_error_message()" will return a string describing the error.
Ri3156b_load_FSK_data
Description
Loads the data stream that will cause the 3156B 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
3156B 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.
Channel Dependency: Independent
Sample FSK Data Array
0 1 1 1 0 1 0 0 0 1
C Syntax
ViStatus ri3156b_load_FSK_data (ViSession instrHandle, ViInt16 FSKWordLength, ViBoolean FSKData[])
Parameters
Name
Variable
Type
Description
instrHandle ViSession The Instrument Handle is used to identify the unique
session or communication channel between the driver
and the instrument. If more than one instrument of the
model type is used, this will be used to differentiate
between them. Note that the initialize function may be
used to associate multiple instrument handles with a
single instrument.