Analog Input Timing Signals - National Instruments PXI-6071E User Manual

Chapter 2 Analog Input

Analog Input Timing Signals

RTSI 7
Master
Timebase
20 MHz
Timebase
E Series User Manual
Figure 2-14. NI-DAQmx Create Virtual Channel.vi
In order to provide all of the timing functionality described throughout this
section, the DAQ-STC provides an extremely powerful and flexible timing
engine. Figure 2-15 summarizes all of the clock routing and timing options
provided by the analog input timing engine.
PFI 0–9,
RTSI 0–6
Onboard
Clock
÷
200
Figure 2-15. Analog Input Timing Engine Clock Routing and Timing Options.
E Series devices use the ai/SampleClock and ai/ConvertClock signals to
perform interval sampling. As Figure 2-16 shows, ai/SampleClock controls
the sample period, which is determined by the following equation:
Ctr0InternalOutput
ai/SampleClock
Onboard
Timebase
Clock
Divisor
Onboard
Clock
Divisor
ai/ConvertClock
Timebase
1/sample period = sample rate
2-30
PFI 0–9,
RTSI 0–6
ai/SampleClock
÷
ai/Convert
÷
Clock
PFI 0–9,
RTSI 0–6
Ctr0InternalOutput
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