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Chapter 5
Functional Overview
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National Instruments Corporation
5-5
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VXI interrupt
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For more advanced features, please contact National Instruments
The NI-VXI/VISA software makes it easy to use NI WatchDOG. The
NI WatchDOG has a 32 kHz reference clock to clock an 8-bit prescaler that
then clocks an 8-bit counter to accommodate timeouts up to 2 seconds.
Real-Time Clock
The VXIpc 870 Series uses a standard Y2K compliant real-time clock with
a user-replaceable battery for backing up the CMOS setting.
BIOS
The VXIpc 870 Series uses a 2 Mb flash device for BIOS code. The BIOS
code is based on the AWARD Modular BIOS. The BIOS code incorporates
the VIDEO BIOS and SCSI BIOS in one device. The BIOS is user
upgradable though a flash update utility.
Programmable Reset Circuitry
The programmable reset circuitry on the VXIpc 870 Series simplifies
software development. You can program the circuitry to reset the PC based
on VXI SYSRESET or reset the VXI bus only using NI-VXI.
VXI Voltage Monitor Circuitry
The VXIpc 870 Series has onboard logic to check all VXI backplane
voltages. The
PWROK
status LED indicates when all voltages are present.
This LED can give you a quick indication that something is wrong with the
system. The voltage monitor can be configured to monitor all VXI power
on just the voltages needed by the VXIpc 870 Series.
Fused Power Protection
The VXIpc 870 Series uses resettable fuses on all voltages 5 V.
The +5 V power is a user-replaceable fuse accessible through the rear of
the unit.