Welding System User Manual

Chapter 2 Function Reference — WFM_Rate
NI-DAQ FRM for PC Compatibles 2-438
© National Instruments Corporation
2: 100 kHz clock used as timebase (10 µs resolution).
3: 10 kHz clock used as timebase (100 µs resolution) (Am9513-based MIO devices
only).
4: 1 kHz clock used as timebase (1 ms resolution) (Am9513-based MIO
devices only).
5: 100 Hz clock used as timebase (10 ms resolution) (Am9513-based MIO devices
only).
updateInterval is the number of timebase units that elapse between consecutive writes
(updates) to the D/A converters. The combination of the timebase resolution value and the
updateInterval produces the waveform generation rate you want. You can input the value
returned in updateInterval directly to
WFM_ClockRate.
Range: 2 through 65,535.
Note If you are using an SCXI-1200 with remote SCXI, the maximum rate will depend
on the baud rate setting and updateRate. Refer to the SCXI-1200 User Manual for
more details.
Note C Programmers—timebase and updateInterval are pass-by-reference
parameters.
Using This Function
WFM_Rate produces timebase and update-interval values to closely match the update rate
you want. To calculate the actual 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:
units = 0 (pts/s).
actual rate = 1/(clock resolution
*
updateInterval).
units = 1 (s/pt).
actual rate = clock resolution
*
updateInterval.