National Instruments 1142 用户手册

下载
页码 86
Appendix C
Common Questions
© National Instruments Corporation
C-3
In LabVIEW, can I use different input limits for the same 
SCXI-1141/1142/1143 channel if I repeat the channel in the SCXI 
channel string array?
No. The SCXI-1141/1142/1143 cannot dynamically change the gain 
settings during scanning. Therefore, group channels with similar input 
ranges together in the channel string array. Make sure that repeated 
channels in different indices of the channel string array have the same input 
limits in the corresponding input limits array.
In LabVIEW, can I use a VI to change my SCXI-1141/1142/1143 
configuration settings?
Yes. You can change the configuration settings in NI-DAQmx using 
NI-DAQmx Tasks. In Traditional NI-DAQ (Legacy) you can use the 
AI Parameter VI to change all the SCXI-1141/1142/1143 configuration 
settings. For more information, refer to Chapter 5, 
Some SCXI modules permit flexible scanning. Does the 
SCXI-1141/1142/1143 module permit flexible scanning?
No. You must scan the channels on the SCXI-1141/1142/1143 module in 
consecutive, ascending order. However, you can start the scan with any 
channel.
Are there any cabling restrictions when using an SCXI-1141/1142/1143 
module with a plug-in E/M Series DAQ device?
Yes. If a chassis contains an SCXI-1520, SCXI-1530/1531, or SCXI-1140 
module, at least one of these modules must be the cabled module. A cabled 
module is the module connected directly to the E/M Series DAQ device. 
This ensures that a timing signal is available for use by all 
simultaneous-sampling SCXI modules in the chassis.
What is the power-on state of the SCXI-1141/1142/1143 multiplexer, 
analog bus switches, and configuration settings?
The multiplexer, analog bus switches, and configuration settings are not in 
a known state immediately after power on. All hardware settings are 
programmed automatically when beginning an acquisition in LabVIEW or 
a test panel in MAX.