Programming instructions

Chapter 21 Common SCXI Applications
© National Instruments Corporation 21-19 LabVIEW Data Acquisition Basics Manual
Digital Output Application Example
To output digital signals through an SCXI chassis, you can use the
SCXI-1160, SCXI-1161, SCXI-1163, and SCXI-1163R modules and the
digital Easy Digital VI, Write to Digital Port, as shown in Figure 21-12.
Figure 21-12.
Outputting Digital Signals through an SCXI Chassis
Using Easy Digital VIs
If you configure channels using the DAQ Channel Wizard, digital channel
can consist of a digital channel name. The channel name can refer to either
a port or a line in a port. You do not need to specify device, line, or port
width, as theses inputs are not used by LabVIEW if a channel name is
specified in digital channel.
As an alternative, digital channel can be expressed in the
scx!mdy!0
format, where you are trying to output from the digital output module on
slot
y
of chassis
x
. The last identifier is always port 0, because the whole
module is considered one port. In this case, you must also specify device
and port width. The port width should be the number of lines on your
SCXI module if you are operating in multiplexed mode. The SCXI-1160
has 16 relays, the SCXI-1161 has 8 relays, and the SCXI-1163/1163R have
32 relays. You can not use the SCXI-1160 or SCXI-1161 in parallel mode.
For the SCXI-1163/1163R the port width in parallel mode should be the
number of lines on your DAQ device or SCXI-1200 module. The DIO-32F
device can access all 32 lines of the SCXI-1163/1163R modules at once by
using the SCXI-1348 cable assembly. The DIO-24 and the DIO-96 devices
can only access the first 24 lines of the SCXI-1163/1163R when configured
in parallel mode. For the fastest performance in parallel mode, you can use
the appropriate onboard port numbers instead of the SCXI channel string
syntax.
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