VTI Instruments EX1629, Руководство пользователя

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VTI Instruments Corp.
290 EX1629 Command Set
vtex1629_set_trigger_delay
F
UNCTION
P
ROTOTYPE
ViStatus vtex1629_set_trigger_delay (ViSession vi , ViReal64 delay );
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.
delay = a real input value, in seconds, indicating the desired trigger delay. Valid input values: 0 s to 4294.967295 s.
D
ATA
I
TEM
R
ESET
V
ALUE
delay = 0.000000000
D
ESCRIPTION
This function sets the trigger delay for the EX1629. Specifically, this is the amount of time, in seconds, that the
EX1629 will wait after receiving a TRIG event before it begins to acquire data.
The actual delay exhibited by the EX1629 is dependent on the sample frequency, set by calling the
vtex1629_set_sample_frequency function. The actual delay will be a multiple of the sample time. For example, if
the sample frequency is 1 kHz, the sample time is 1 ms. If the trigger delay is set to a value less than 0.5 ms, the
EX1629 will experience no delay. If the trigger delay is set to a value between 0.5 ms and 1.49 ms, the delay
exhibited will be 1 ms.
As a result, it is best practice to perform a vtex1629_get_arm_delay call after a vtex1629_set_trigger_delay or a
vtex1629_set_sample_frequency call is performed to determine the actual delay.
E
XAMPLE
ViSession instrumentHandle;
ViStatus status;
…
status = vtex1629_set_trigger_delay(instrumentHandle, 0.01);