Programming instructions

Chapter 19 Hardware and Software Setup for Your SCXI System
LabVIEW Data Acquisition Basics Manual 19-6
© National Instruments Corporation
When you use the analog input VIs, specify the correct onboard channel for
each parallel SCXI channel. If you are using a range of SCXI channels,
LabVIEW assumes the onboard channel numbers match the SCXI channel
numbers. Refer to the
SCXI Channel Addressing
section in Chapter 20,
Special Programming Considerations for SCXI
, for the proper SCXI
channel syntax.
Parallel Mode for the SCXI-1200 (Windows)
In parallel mode, the SCXI-1200 reads only its own analog input channels.
The SCXI-1200 does not have access to the analog bus on the SCXI
backplane in parallel mode. You should use parallel mode if you are not
using other SCXI analog input modules in the chassis with the SCXI-1200.
Parallel Mode for Digital Modules
When you operate a digital module in parallel mode, the digital lines on
your DAQ device directly drive the individual digital channels on your
SCXI module. You must cable a DAQ device directly to every module
operated in parallel mode.
You may want to use parallel mode instead of multiplexed mode for faster
updating or reading of the SCXI digital channels. For the fastest
performance in parallel mode, you can use the appropriate onboard port
numbers instead of the SCXI channel string syntax in the digital VIs. Refer
to the hardware tables in Appendix B,
Hardware Capabilities
, in the
LabVIEW Function and VI Reference Manual
for the digital ports used in
parallel mode on each DAQ device, or refer to the LabVIEW
Online
Reference
, by selecting
Help»Online Reference…
.
Note
If you are using a DIO-96, an AT-MIO-16D, or an AT-MIO-16DE-10 device, you
can also operate a digital module in parallel mode using the digital ports on the
second half of the NB5 or R1005050 ribbon cable (lines 51
– 100). Therefore, the
DIO-96 can operate two digital modules in parallel mode, one module using the
first half of the ribbon cable (lines 1
– 50), and another module using the second
half of the ribbon cable (lines 51
– 100).
SCXI Software Installation and Configuration
After you assemble your SCXI system, you must run the configuration
utility to enter your SCXI configuration. LabVIEW needs the configuration
information to program your SCXI system correctly. Refer to Chapter 2,
Installing and Configuring Your Data Acquisition Hardware
.