Measurement Computing UL for NI LabVIEW User Manual
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Universal Library Virtual Instruments (VIs)
Analog Input VIs
Caution!
You will generate an error if you specify a total A/D rate beyond the capability of the board.
For example, if you specify LowChan = 0, HighChan = 7
(8 channels total) and Rate = 40,000 and you are using a PCI-DAS6025, you will get an error.
You have specified a total rate of 8 x 40,000 = 320,000. The PCI-DAS6025 is capable of
converting 200,000 samples per second. The maximum sampling rate depends on the A/D
board that is being used. It is also dependent on the sampling mode options.
Range
If the selected A/D board does not have a programmable range feature, then this
argument will be ignored. Otherwise the gain can be set to any of the following
ranges that are supported by the selected A/D board. Refer to board-specific
information for the list of ranges supported by each board. See the "
" table on page 19 for valid values.
Refer to board-specific information contained in the Universal Library User's
Guide (available on our we
a list of the A/D ranges supported by each board.
Options
For a detailed explanation of the
Options
field refer to OptAIn.VI on page 30.
The OptAIn.VI must be wired to this input.
InterChannel Delay
Delay in seconds between channels in a scan. Negative values indicate that the
interchannel delay will automatically be minimized. Currently, positive values will
result in interchannel delays corresponding to the
Rate
sampling rate. For example:
1/(
Rate
*(
HighChan
-
LowChan
+1)).
ErrCode
Error code returned from the Universal Library. Zero if no error occurred. Use the
ErrMsg VI to convert
ErrCode
into a readable string.
Important - Read board-specific information in UL User's Guide
In order to understand the functions, read the board-specific information contained in the Universal Library
User's Guide (available on our web site at
example programs should be examined and run prior to attempting any programming of your own.
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