©
National Instruments Corporation
E-1
E
Common Questions
This appendix answers common questions you may have when using the
VXIpc 870 Series.
What do the LEDs on the front of the VXIpc 870 Series mean?
Refer to Appendix B,
, for a description of the front
panel LEDs.
Is something wrong if the red SYSF and FAIL LEDs stay lit after
booting the VXIpc 870 Series?
If either the
SYSF
or
FAIL
LED remains lit, refer to Appendix B,
, for troubleshooting steps.
Can I access 32-bit registers in my VXIbus system from the VXIpc 870
Series?
Yes. The VXIpc 870 Series uses the 32-bit PCI bus to interface to the
VXIbus. In fact, its VXIbus circuitry also supports the VME64 standard for
D64 accesses.
What kind of signal is CLK10 and what kind of signal do I need for an
external CLK10?
CLK10 is a differential ECL signal on the backplane. However, because
the oscillator and the EXTCLK input on the front panel use TTL levels,
you need to supply a TTL-level signal for EXTCLK. Our voltage
converters convert the signal to differential ECL.
What is the accuracy of the CLK10 signal?
The CLK10 signal generated by the VXIpc 870 Series is ±100 ppm (0.01%)
as per the VXIbus specification. If you need a more accurate CLK10 signal,
you can use the CLKI/O connector on the front panel.
