VTI Instruments EX1629, Руководство пользователя

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VTI Instruments Corp.
234 EX1629 Command Set
vtex1629_set_arm_delay
F
UNCTION
P
ROTOTYPE
ViStatus vtex1629_set_arm_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 arm 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 arm delay for the EX1629. This indicates the amount of time, in seconds, that the EX1629 will
wait after receiving an ARM event before it transitions the trigger state machine from the ARM layer into the TRIG
layer.
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 arm delay is set to a value less than 0.5 ms, the
EX1629 will experience no delay. If the arm 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_arm_delay or a
vtex1629_set_sample_frequency call is performed to determine the actual delay.
E
XAMPLE
ViSession instrumentHandle;
ViStatus status;
…
status = vtex1629_set_arm_delay(instrumentHandle, 0.01);