National Instruments 1128 ユーザーズマニュアル

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Common Questions
This appendix addresses common questions you may have while using 
your SCXI-1127/1128 module.
How fast can I scan with the SCXI-1127/1128 module?
The fastest scan rate for the SCXI-1127 is 100 scans/s, and the fastest scan 
rate for the SCXI-1128 is 1000 scans/s. Typically, when using a DMM to 
make accurate measurements, the DMM requires hundreds of milliseconds. 
Consequently, the DMM becomes the limiting factor in determining the 
scan rate.
What should I do if the software detects the module, but the switches 
do not switch?
Verify that the switches do not switch. Close your application program 
and then launch the soft front panel as described in the Set up and Test 
document you received with your kit. The soft front panel shows the 
state of each relay switch on the module. Try closing and opening the 
switches using the low level switch functions.
Check the return codes of the NI-SWITCH operation to ensure that 
there are no errors (negative values) or warnings (positive values). You 
can also use the NI-Spy utility, which is installed with NI-SWITCH, 
to check for error codes.
Finally, verify that your code is correct. For reference, see the 
examples described in the NI-SWITCH Software User Manual
NI-SWITCH also ships with several examples in source code. 
Compare your algorithm to the ones in the examples.
What should I do if scanning does not work in the handshaking mode 
with a third-party DMM?
Ensure that you have configured the SCXI-1127/1128 and the 
instrument to correctly route all the trigger lines. The output trigger 
of the instrument should connect to the trigger input of the 
SCXI-1127/1128. In addition, make sure the scanner advanced trigger 
of the SCXI-1127/1128 connects to the input trigger of the instrument.