3156B User Manual
Racal Instrument © 2005
Programming Reference 5-73
Ri3156b_set(query)_arb_sampling_freq
Description
Sets the sample clock frequency. Users should be careful not to confuse waveform frequency with sample
clock frequency. The waveform frequency parameter is valid for standard waveforms only and controls
waveform frequency at the output connector. On the other hand, the sample clock frequency parameter is valid
for arbitrary waveforms only and defines the frequency of which the generator clocks data points.
Standard waveform frequency is measured in units of Hz. Arbitrary waveform sample clock frequency is
measured in units of S/s (samples per second). The frequency of a given arbitrary waveform at the output
connector is computed using the sample clock frequency and the number of data points.
Use the following equation for computing the frequency of an arbitrary waveform:
Waveform Frequency = Sample Clock / Number of Data Points
Channel Dependency: Common
C Syntax
ViStatus ri3156b_set_arb_sampling_freq (ViSession instrHandle, ViReal64 samplingClock)
ViStatus ri3156b_query_arb_sampling_freq (ViSession instrHandle, ViReal64 * samplingClock)
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.
samplingClock
ViReal64
Programs the sample clock frequency for the 3156B.
Valid range: 1 to 200e6 (S/s)
Default: 50e6
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.
