Local Bus; Trigger Bus; Figure 1-3. Pxi Local Bus And Star Trigger Routing - National Instruments PXI PXITM -1000 User Manual

Chapter 1 Getting Started

Local Bus

Trigger Bus

PXI-1000 User Manual
The PXI backplane's local bus is a daisy-chained bus that connects each
peripheral slot with its adjacent peripheral slots to the left and right, as
shown in Figure 1-3.
For example, a given peripheral slot's right local bus connects to the
adjacent slot's left local bus and so on. Each local bus is 13 lines wide and
can pass analog signals between cards or provide a high-speed side-band
communication path that does not affect the PXI bandwidth.
Local Bus signals may range from high-speed TTL signals to analog
signals as high as 42 V. Initialization software keys adjacent boards to
prohibit the use of incompatible boards. This software uses the
configuration information specific to each peripheral board to evaluate
compatibility. This method is a flexible way to define local bus
functionality that is not limited by hardware keying.
Local Local
Bus Bus
PCI Arbitration and Clock Signals

Figure 1-3. PXI Local Bus and Star Trigger Routing

The eight PXI trigger lines are bused to each slot. You can use the trigger
lines in a variety of ways. For example, you can use triggers to synchronize
the operation of several different PXI peripheral modules. In other
applications, one module can control carefully timed sequences of
Star Triggers
1-6
Local
Bus
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