National Instruments DAQ X NI 634 Series, User Manual

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X Series User Manual
Using an External Source
You can route any of the following signals as Counter n Sample Clock:
• PFI <0..15>
• RTSI <0..7>
• PXI_STAR
• PXIe_DSTAR<A,B>
• Analog Comparison Event
You can sample data on the rising or falling edge of Counter n Sample Clock.
Routing Counter n Sample Clock to an Output Terminal
You can route Counter n Sample Clock out to any PFI <0..15> terminal. The PFI circuitry inverts
the polarity of Counter n Sample Clock before driving the PFI terminal.
Counter n Internal Output and Counter n TC Signals
The Counter n Internal Output signal changes in response to Counter n TC.
The two software-selectable output options are pulse output on TC and toggle output on TC. The
output polarity is software-selectable for both options.
With pulse or pulse train generation tasks, the counter drives the pulse(s) on the Counter n
Internal Output signal. The Counter n Internal Output signal can be internally routed to be a
counter/timer input or an “external” source for AI, AO, DI, or DO timing signals.
Routing Counter n Internal Output to an Output Terminal
You can route Counter n Internal Output to any PFI <0..15>, RTSI <0..7>, or PXIe_DSTARC
terminal. All PFIs are set to high-impedance at startup.
Frequency Output Signal
The Frequency Output (FREQ OUT) signal is the output of the frequency output generator.
Routing Frequency Output to a Terminal
You can route Frequency Output to any PFI <0..15> or PXIe_DSTARC terminal. All PFIs are
set to high-impedance at startup. The FREQ OUT signal can also be routed to DO Sample Clock
and DI Sample Clock.