VTI Instruments EX1629, Руководство пользователя

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EX1629 Command Set 183
vtex1629_get_settling_time
F
UNCTION
P
ROTOTYPE
ViStatus vtex1629_get_settling_time (ViSession vi , ViInt32 channel , ViPReal64 settling_time );
F
UNCTION
P
ARAMETERS
vi = contains a session handle to the instrument. This handle is obtained by the function and remains valid until the
session is closed.
channel = an integer input value that specifies the channel for which the settling time will be returned. Valid input
values: 0 to 47.
settling_time = a real return value that indicates the settling time (in seconds) of the specified channel.
D
ATA
I
TEM
R
ESET
V
ALUE
Not applicable to this function.
D
ESCRIPTION
This function queries and returns the current settling time for a particular channel. Settling time is defined as the
amount of time, in seconds, taken by the EX1629 signal conditioning module to settle to the input vale ± 2% of the
input value after a reset of the signal conditioning path. The signal conditioning path is reset on a sync event. The
settling time is a function of the sampling frequency and the IIR filter settings. As such, disabling the IIR filters does
not make sampling time “0”.
NOTE The signal conditioning path is reset on a sync event, which means that acquisition data will not
reflect the input signals until
settling_time seconds have elapsed. Settling times will vary between
channels, depending on the channel’s filter configuration. The recommended technique is to
configure the instrument completely, query each channel’s settling time delay, and then delay for
the maximum of these settling delays after issue a sync (vtex1629_soft_synch) prior to initiating
acquisition.
E
XAMPLE
ViSession instrumentHandle;
ViStatus status;
ViReal64 settling_time;
…
status = vtex1629_get_settling_time(instrumentHandle, 0, &settling_time);