Chapter 10 Easy I/O for DAQ Library
© National Instruments Corporation 10-7 LabWindows/CVI Standard Libraries
Channel String for Analog Output Functions
The second parameter to most of the analog output functions is the channel string containing the
analog output channels that are to be driven.
Refer to the chapter specific to your DAQ device in the DAQ Hardware Overview Guide to
determine what channels are valid for your hardware. The document is an Adobe Acrobat file,
daqhwov.pdf, that you can view on screen and also print. daqhwov.pdf is part of a set of
.pdf files that come with every DAQ device sold by National Instruments.
The syntax for the Channel String is as follows:
• If you are using a DAQ device without SCXI, list the channels to be driven, as in the
following example:
"0,2,5" /* drives channels 0, 2, and 5 */
"0:3" /* drives channels 0 through 3 inclusive */
• If you are using SCXI, you can address SCXI channels when you attach one or more SCXI
chassis to a plug-in data acquisition board.
The SCXI channel syntax is as follows:
"SCx!MDy!a" /* channel a on the module in slot y of the chassis with ID x */
"SCx!MDy!a:b" /* channels a through b inclusive on the module in slot y of
the chassis with ID x */
SCXI channel ranges cannot cross module boundaries. SCXI channel ranges must always
increase in channel number.
Valid Counters for the Counter/Timer Functions
The second parameter to most of the counter/timer functions is the counter used for the
operation. The valid counters you can use depends on your hardware as shown in Table 10-2.
Table 10-2. Valid Counters
Device Type Valid Counters
DAQ-STC Devices 0 and 1
Am9513 MIO boards 1, 2, and 5
PC-TIO-10 1 through 10
EISA-A2000 2