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National Instruments Corporation
E-1
PXI-846x and NI-CAN for Windows 98/95
E
RTSI Bus
This appendix describes the RTSI interface on your PXI-846
x
series board.
RTSI, PXI and CompactPCI
Using PXI-compatible products with standard CompactPCI products is an
important feature provided by the
PXI Specification
, Revision 1.0. If you
use a PXI-compatible plug-in device in a standard CompactPCI chassis,
you will be unable to use PXI-specific functions, but you can still use the
basic plug-in device functions. For example, the RTSI bus on your
PXI-846
x
series board is available in a PXI chassis, but not in a
CompactPCI chassis. The CompactPCI specification permits vendors to
develop sub-buses that coexist with the basic PCI interface on the
CompactPCI bus. Compatible operation is not guaranteed between
CompactPCI devices with different sub-buses nor between CompactPCI
devices with sub-buses and PXI. The standard implementation for
CompactPCI does not include these sub-buses. Your PXI-846
x
device will
work in any standard CompactPCI chassis adhering to the
PICMG 2.0 R2.1
CompactPCI
core specification using the 64-bit definition for J2. PXI
specific features are implemented on the J2 connector of the CompactPCI
bus. Table E-1 lists the J2 pins your PXI-846
x
series board uses. Your PXI
board is compatible with any CompactPCI chassis with a sub-bus that does
not drive these lines. Even if the sub-bus is capable of driving these lines,
the board is still compatible as long as those pins on the sub-bus are
disabled by default and not ever enabled. Damage may result if these lines
are driven by the sub-bus.
The PXI-8461 one port and two port boards allow for the connection of four
RTSI input signals and four RTSI output signals.In order to fully support
the fault reporting capabilities of the low-speed transceivers used on the
PXI-8460 one port, PXI-8460 two port, and PXI-8462, three RTSI lines on
those boards are reserved for low-speed CAN fault reporting. This allows
for the connection of three RTSI input signals and two RTSI output signals
to the boards, providing them the real time synchronization benefits of
RTSI without sacrificing low-speed CAN fault reporting.
