©NationalInstruments Corporation E-1 PXI-846xand NI-CAN for Windows NT
E

RTSI Bus

Thisappendix describes t he RTSIinterface on your PXI-846xseries board.

RTSI, PXI and CompactPCI

Using PXI-compatible products with standard CompactPCI products is
an important feature providedby the PXI Specification,Revision1.0.
Ify ou use a PXI-compatible plug-in devicein a standard Com pactPCI
chassis,you will be unable to use PXI-specific functions, but you can
still use the basic plug-in device functions. For example, the RTSIbus
onyour PXI-846xseries board is availablein a PXI chassis, but not in
aC ompactPCI chassis. The CompactPCI specification permits vendors
to developsub-buses that coexist with the basic PCI interface on the
CompactPCI bus.Compatible operation is not guaranteed between
CompactPCId eviceswith different sub-buses nor between CompactPCI
deviceswith sub-buses and PXI. The standard implementation for
CompactPCI does not include these sub-buses. YourPXI-846xdevice
willwork in any standard CompactPCI chassis adhering to the PICMG 2.0
R2.1CompactPCI core specification using the 64-bit definition for J2. PXI
specificfeatures are implemented on the J2 connector of the CompactPCI
bus.Table E-1 lists the J2 pins your PXI-846xseries board uses. YourPXI
boardis compatible with any CompactPCI chassis with a sub-bus that does
not drivethese 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 bydefault and not ever enabled. Damage may result if these
linesare driven by the sub-bus.
ThePXI-8461 one port and two port boards allow for the connection of four
RTSIinput signals and four RTSI output signals. In order to fully support
the faultreporting capabilities of the low-speed transceivers used on the
PXI-8460one port, PXI-8460 two port, and PXI-8462,three RTSI lines on
those boards are reservedfo r low-speedCAN fault reporting. This allows
forthe connection of three RTSI input signals and two RTSI output signals
to the boards, providing them the real time synchronization benefits of
RTSIwithout sacrificing low-speed CAN fault reporting.