ADLINK PXIS-3320 - Manual (Page 18)

10 Chassis Overview
Star Trigger Slot
Slot 2 is designated as the Star Trigger (ST) slot. This slot features
a dedicated trigger line between itself and slots 3 to 15. The star
trigger delivers trigger signals with ultra-low skew (<1ns) to periph-
eral modules. To use the star trigger functionality, you must install
a special star trigger controller in Slot 2.
Peripheral Slots
The PXIS-3320 chassis backplane accommodates up to fourteen
6U PXI/CompctPCI peripheral modules.
Local Bus
The PXI backplane’s local bus is a daisy-chained bus that con-
nects each peripheral slot with the slots on its left and right. Each
local bus is 14 lines wide and can pass analog and digital signals
between modules or provide a high-speed, sideband communica-
tion path that does not affect the PCI bandwidth.
Following PXI specifications, the local bus connects all adjacent
slots except Slots 1 and 2.
Trigger Bus
The backplane’s trigger bus is an 8-line bus that connects all slots
in the same PCI segment. Users can use triggers to synchronize
the operation of several PXI peripheral modules, or use one mod-
ule to control accurate timing sequences of operations performed
on other modules in the system. Modules can pass trigger signals
or clock signals to other modules through the trigger bus, allowing
precise timed responses to asynchronous external events that the
system is monitoring or controlling.