National Instruments 321645c-01 用户手册

Chapter 2

Function Reference — WFM_Rate

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NI-DAQ FRM for PC Compatibles

Converts a waveform generation update rate into the timebase and update-interval values 
needed to produce the rate you want.

rate is the waveform generation update rate you want. rate is expressed in either pts/s or 
seconds per point (s/pt), depending on the value of the units parameter.

Range:

Roughly 0.00153 pts/s through 500,000 pts/s or 655 s/pt through 0.000002 s/pt.

units indicates the units used to express rate.

0:

pts/s.

1:

s/pt.

timebase is a code representing the resolution of the onboard clock signal that the device uses 
to produce the update rate you want. You can input the value returned in timebase directly to 

WFM_ClockRate

. timebase has the following possible values:

–3:

20 MHz clock used as a timebase (50 ms) (E Series only).

–1:

5 MHz clock used as timebase (200 ns resolution) (AT-MIO-16F-5, 
AT-MIO-64F-5, and AT-MIO-16X only).

1:

1 MHz clock used as timebase (1 µs resolution) (Am9513-based MIO 
devices only).

f64

update rate you want

i16

units used

i16

resolution of clock signal

u32

number of timebase units