National Instruments Welding System 321645c-01 用户手册
Chapter 2
Function Reference — DAQ_Start
NI-DAQ FRM for PC Compatibles
2-136
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National Instruments Corporation
DAQ_Start
Format
status = DAQ_Start (deviceNumber, chan, gain, buffer, count, timebase, sampInterval)
Purpose
Initiates an asynchronous, single-channel DAQ operation and stores its input in an array.
Input
Output
Parameter Discussion
chan is the analog input channel number. If you are using SCXI, you must use the appropriate
analog input channel on the DAQ device that corresponds to the SCXI channel you want.
Select the SCXI channel using
analog input channel on the DAQ device that corresponds to the SCXI channel you want.
Select the SCXI channel using
SCXI_Single_Chan_Setup
before calling this function.
Refer to the NI-DAQ User Manual for PC Compatibles for more information on SCXI
channel assignments.
channel assignments.
Range:
.
gain is the gain setting to be used for that channel. This gain setting applies only to the DAQ
device; if you are using SCXI, you must establish any gain you want at the SCXI module
either by setting jumpers on the module or by calling
device; if you are using SCXI, you must establish any gain you want at the SCXI module
either by setting jumpers on the module or by calling
SCXI_Set_Gain
. Refer to Appendix B,
, for valid gain settings. If you
use invalid gain settings, NI-DAQ returns an error. NI-DAQ ignores gain for the 516 and LPM
devices and DAQCard-500/700.
devices and DAQCard-500/700.
Name
Type
Description
deviceNumber
i16
assigned by configuration utility
chan
i16
analog input channel number
gain
i16
gain setting
count
u32
number of samples to be acquired
timebase
i16
timebase value
sampInterval
u16
sample interval
Name
Type
Description
buffer
[i16]
used to hold acquired readings