NI SCXI-1127 User Manual page 76

Appendix E Common Questions
SCXI-1127 User Manual
• If you use the DMM to initiate the scan, enable scanning on the
SCXI-1127 before configuring the DMM to start taking
measurements. This is the recommended method for scanning.
• Be sure to 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.
• Verify that your code is correct. For reference, see the examples
described in the NI-SWITCH Software User Manual. The NI-SWITCH
driver also ships with several examples in source code. Compare your
algorithm to the ones in the examples.
Do I need to program the SCXI-1127 myself?
The SCXI-1127 comes with the NI-SWITCH driver software that exports
the full functionality of the module. NI-SWITCH handles the complex
issues of register writes to the module and operating system interfacing.
Can I plug a non SCXI-1127 module into a slot that has a high-voltage
analog backplane?
Yes. You can plug in a module that does not support the HVAB. The
non-SCXI-1127 module does not connect to the HVAB or the digital
communication lines on the HVAB backplane adapter.
Must I install the complete high-voltage analog backplane?
No. You do not have to install the complete backplane. There may be
instances where it is necessary for a non SCXI-1127 module to
communicate to a device using a different backplane adapter. For example,
using a separate digital module in parallel mode. In this case, you can
remove that segment of the HVAB although it is important that you do not
remove the section of the HVAB that is controlling the chassis.
Can I use the HVAB for matrix expansion?
Yes. You can use the HVAB backplane to connect the matrix rows together.
For example you can create a 16x8 matrix in a 4-slot chassis. First install
four SCXI-1127s into the chassis. Now you have four independent 8x4
matrices. Now if you install the 2-slot HVAB-backplane adapter behind
slots 3 and 4 you have connected the rows between slot 3 and 4 which
creates a 16x4 matrix. Now install the two 1-slot adapters behind slots 1 and
2. Connect the two 1-slot adapters together with an 8-position HVAB plug.
Do not connect the 2-slot HVAB-backplane adapter to the 1-slot adapters
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