Chapter 1
Introduction
1-10
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System Controller Slot
The System Controller slot is located in Slot 1 of the chassis as defined by
the PXI specification. It has three controller expansion slots, which are
used for system controller modules wider than one slot. As defined in the
PXI specification, these slots allow the controller to expand to the left so it
does not use up peripheral slots.
Peripheral Slots
The PXI-1050 has seven peripheral slots located in Slots 2 through 8. You
can use PXI modules in peripheral slots to add functionality to the PXI
subsystem not already provided by the system controller. Examples of PXI
peripheral modules are multifunction I/O, digital I/O, and instrument
modules. Some peripheral slots also have special capabilities, such as the
Star Trigger slot and the SCXI Control slot, which are explained in the
following sections.
Star Trigger Slot
The Star Trigger slot is located at Slot 2. This slot has a dedicated trigger
line between each peripheral slot (refer to Figure 1-4) and is intended for
modules with Star Trigger functionality to provide individual triggers to all
other peripherals. However, if you do not require advanced trigger
functionality, you can install any standard peripheral module into this slot.
Local Bus
The PXI backplane local bus is a daisy-chained bus that connects each
peripheral slot with its adjacent left and right peripheral slots, as shown in
Figure 1-4.
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 modules 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 modules to prohibit
the use of incompatible devices. This software uses the configuration
information specific to each peripheral module to evaluate compatibility.
This method is a flexible way to define local bus functionality that is not
limited by keying hardware.
