Pxi Express Considerations; Ni Sc Express Clock And Trigger Signals; Pxie_Clk100; Pxie_Sync100 - National Instruments SC Express PXIe-4357 User Manual

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PXI Express Considerations

This chapter details the clock and trigger functionality available through the PXI Express chassis
for the NI PXIe-4357.

NI SC Express Clock and Trigger Signals

PXIe_CLK100

PXIe_CLK100 is a common low-skew 100 MHz reference clock for synchronization of multiple
modules in a PXI Express measurement or control system. The PXI Express backplane is
responsible for generating PXIe_CLK100 independently to each peripheral slot in a
PXI Express chassis. For more information, refer to the PXI Express Specification at
.
www.pxisa.org

PXIe_SYNC100

PXIe_SYNC100 is a common low-skew 10 MHz reference clock with a 10% duty cycle for
synchronization of multiple modules in a PXI Express measurement or control system. This
signal is used to accurately synchronize modules using PXIe_CLK100 along with those using
PXI_CLK10. The PXI Express backplane is responsible for generating PXIe_SYNC100
independently to each peripheral slot in a PXI Express chassis. For more information, refer to
the PXI Express Specification at .
www.pxisa.org

PXI_CLK10

PXI_CLK10 is a common low-skew 10 MHz reference clock for synchronization of multiple
modules in a PXI measurement or control system. The PXI backplane is responsible for
generating PXI_CLK10 independently to each peripheral slot in a PXI chassis.
PXI_CLK10 cannot be used as a reference clock for SC Express modules.
Note

PXI Triggers

A PXI chassis provides eight bused trigger lines to each module in a system. Triggers may be
passed from one module to another, allowing precisely timed responses to asynchronous
external events that are being monitored or controlled. Triggers can be used to synchronize the
operation of several different PXI peripheral modules.
On SC Express modules, the eight PXI trigger signals are synonymous with RTSI <0..7>.
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