Defining NI-Sync Clock Terminals

Using niSync Connect Clock Terminals, you can route clocks between chassis, discipline the PXI backplane clock to the oscillator of a system timing module, or route an external time reference throughout a chassis or to multiple chassis. The VI uses clock terminals to route clock signals between devices. The following terminals are available with NI-Sync:

Note Note  Not all of the following terminals are available on every PXI or PXIe chassis. Refer to your hardware documentation to determine if your device supports a particular source or destination terminal.

Clock Source Terminals

Clock SourceDescription
ClkInThe ClkIn input connector on the front panel of your device. Using ClkIn, you can connect a 10 MHz reference clock directly to the PXI_Clk10_In pin. You also can phase lock a clock connected to ClkIn using a PLL circuit, or you can use a clock connected to ClkIn as the synchronization clock for the front and rear zones of your chassis.
PXI_Clk10The 10 MHz backplane clock of the PXI or PXIe chassis.
OscillatorThe oscillator of the device specified in the instrument handle terminal.
DDS ClockThe DDS signal generated by the device specified in the instrument handle terminal.
PFI_LVDS<n>The PFI low voltage differential signaling (LVDS) input/output connectors on the front panel of your device. PFI LVDS lines consist of paired PFI lines. You can use PFI_LVDS to route clock and trigger signals between multiple PXIe chassis at high speeds. You can achieve faster speeds when using an LVDS line compared to a single-ended PFI line. Signals on PFI LVDS lines use the standard PFI synchronization clock.
PXIe_DStarC<n>The differential star trigger line of your PXIe chassis. Use DStarC lines to route clock and/or trigger signals from a peripheral slot to a system timing slot.
Note Note  Each PXIe_DStarC trigger is mapped to a single slot. This mapping is vendor specific. Refer to your chassis' documentation for more information on the mapping of differential star trigger lines.
PXIe_DStarAThe differential star trigger line of your PXIe chassis. Use DStarA lines to route clock signals from a system timing slot to a peripheral slot.
Note Note  Each PXIe_DStarA trigger is mapped to a single slot. This mapping is vendor specific. Refer to your chassis' documentation for more information on the mapping of differential star trigger lines.

Clock Destination Terminals

Clock DestinationDescription
PXI_Clk10_InThe connector pin that you use to provide the backplane with a reference 10 MHz signal from the system timing slot. When you connect a signal to this pin, PXI_Clk10 and PXIe_Clk100 are phase aligned to this reference.
ClkOutThe ClkOut connector on the front panel of your device. Use this terminal to export clocks to an external device or to another chassis. You can export only clock signals through the ClkOut connector.
BoardClkThe timekeeper used to schedule future time events and timestamping on PXI-6682, PXI-6682H, PXI-6683, and PXI-6683H modules. BoardClk accepts a 10 MHz reference clock and multiplies it by 10 to create a 100 MHz clock for use as a timekeeper. The only two valid sources for BoardClk are the on-board oscillator and PXI_Clk10. You can specify the source of BoardClk using the niSync Connect Clock Terminals VI.
Note Note  BoardClk is a valid terminal only on PXI-668x devices.
PFI_LVDS<n>The PFI_LVDS output connector on the front panel of your device.
PXIe_DStarA<n>The differential star trigger line of your PXIe chassis. Use DStarA lines to route clock signals from the system timing slot to a peripheral slot of your chassis.