National Instruments Welding System 321645c-01 사용자 설명서

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Chapter 2
Function Reference — SCAN_to_Disk
NI-DAQ FRM for PC Compatibles
2-316
©
 National Instruments Corporation
chans is an integer array of a length not less than numChans that contains the onboard 
channel scan sequence to be used. chans can contain any analog input channel number in any 
order. For channel number ranges, refer to Table B-1 in Appendix B, 
. For example, if numChans = 4 and if chans[1] = 7, 
the second channel to be scanned is analog input channel 7, and NI-DAQ scans four analog 
input channels.
Note
The channels contained in the chans array refer to the onboard channel numbers.
If you use one or more external multiplexer devices (AMUX-64Ts), with any MIO or AI 
device except the MIO-64, the total number of channels scanned equals (four-to-one 
multiplexer) * (number of onboard channels scanned) * (number of external multiplexer 
devices), or the total number of channels scanned equals (4) * (numChans) * 
(num_mux_brds). For example, if you use one AMUX-64T and scan eight onboard channels, 
the total number of channels scanned equals (4) * (8) * (1) = 32.
If you use one or more external multiplexer devices (AMUX-64Ts) with the MIO-64, the total 
number of channels scanned equals (4) * (numChans1) * (num_mux_brds) + numChans2
where:
4 represents a four-to-one multiplexer.
numChans1 is the number of onboard channels (of an MIO or AI connector) scanned. 
Range: 0 through 7 differential, 0 through 15 single-ended.
num_mux_brds is the number of external multiplexer devices.
numChans2 is the number of onboard channels (of an analog connector) scanned.
Range: 0 through 23 differential, 0 through 48 single-ended.
If you use SCXI, you must scan the analog input channels on the DAQ device that 
corresponds to the SCXI channels you want. You should select the SCXI scan list using 
SCXI_SCAN_Setup
 before you call this function. Refer to the NI-DAQ User Manual for 
PC Compatibles for more information on SCXI channel assignments.
gains is an integer array of a length not less than numChans that contains the gain setting to 
be used for each channel in the scan sequence selected in chans. NI-DAQ applies the gain 
value contained in gains[n] to the channel number contained in chans[n] when the function 
scans that channel. This gain setting applies only to the DAQ device; if you use 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 an invalid gain, NI-DAQ returns 
an error.