3156B User Manual
Programming Reference 5-102
Racal Instrument © 2005
Ri3156b_set(query)_FM_mod_waveform
Description
The modulating waveform can be selected from 4 built-in waveforms: Sine, Triangle, Ramp and Square. In
addition, One may use and arbitrary waveform to modulate the carrier wave; In this case, an arbitrary waveform
data has to be downloaded to the 3156B using the ri3156B_load_arb_FM_mod_data function. Use the
description in the ri3156B_load_arb_FM_mod_data function to properly prepare and download data to the
arbitrary FM waveform memory.
Channel Dependency: Common
C Syntax
ViStatus ri3156b_set_FM_mod_waveform (ViSession instrHandle, ViReal64 FMmodulationWaveform)
ViStatus ri3156b_query_FM_mod_waveform (ViSession instrHandle, ViReal64 * FMmodulationWaveform)
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.
FMmodulationWaveform
ViInt16
Selects one of 4 built-in waveforms, or arbitrary waveform
to modulate the carrier.
Valid range: 0 to 4
0 – selects sine
1 – selects triangle
2 – selects ramp
3 – selects square
4 – selects arbitrary
Default: 0
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.