National Instruments Welding System 321645c-01 Manual De Usuario

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Chapter 2
Function Reference — WFM_Op
NI-DAQ FRM for PC Compatibles
2-434
©
 National Instruments Corporation
WFM_Op
Format
status = WFM_Op (deviceNumber, numChans, chanVect, buffer, count, iterations, rate)
Purpose
Assigns a waveform buffer to one or more analog output channels, selects the rate and the 
number of times the data in the buffer is to be generated, and starts the generation. If the 
number of buffer generations is finite, 
WFM_Op
 waits for completion before returning, unless 
you call 
Timeout_Config
.
Parameters
Input   
Parameter Discussion
numChans indicates the number of analog output channels specified in the array chanVect.
chanVect is the array of channel numbers indicating which analog output channels are to 
receive output data from the buffer.
Channel number range:
0 or 1 for most devices.
0 through 5 for AT-AO-6.
0 through 9 for AT-AO-10.
buffer is an array of integer values that DACs convert to voltages. If your device has 12-bit 
DACs, these data will range from 0 to 4,095 in unipolar mode and from –2,048 to 2,047 in 
bipolar mode. If your device has 16-bit DACs, data will range from 0 to 65,535 in unipolar 
mode and from –32,768 to +32,767 in bipolar mode. 
Name
Type
Description
deviceNumber
i16
assigned by configuration utility
numChans
i16
number of analog output channels
chanVect
[i16]
channel numbers
buffer
[i16]
values that are converted to voltages by DACs
count
u32
number of points in the buffer
iterations
u32
number of times the waveform generation steps 
through buffer
rate
f64
desired rate in pts/s