Справочник Пользователя для National Instruments Welding System 321645c-01
Chapter 2
Function Reference — DAQ_Rate
©
National Instruments Corporation
2-133
NI-DAQ FRM for PC Compatibles
1:
1 µs.
2:
10 µs.
3:
100 µs.
4:
1 ms.
5:
10 ms.
sampleInterval is the number of timebase units that elapse between consecutive A/D
conversions. The combination of the timebase resolution value and the sampleInterval
produces the DAQ rate you want.
conversions. The combination of the timebase resolution value and the sampleInterval
produces the DAQ rate you want.
Range:
2 through 65,535.
Note
C Programmers—timebase and sampleInterval are pass-by-reference
parameters.
parameters.
Using This Function
DAQ_Rate
produces timebase and sample-interval values to closely match the DAQ rate you
want. To calculate the actual acquisition rate produced by these values, first determine the
clock resolution that corresponds to the value timebase returns. Then use the appropriate
formula below, depending on the value specified for units:
clock resolution that corresponds to the value timebase returns. Then use the appropriate
formula below, depending on the value specified for units:
units = 0 (pts/s):
actual rate = 1/(clock resolution * sampleInterval)
units = 1 (s/pt):
actual rate = clock resolution * sampleInterval