Chapter 2
Analog Input
2-30
ni.com
Figure 2-14.
NI-DAQmx Create Virtual Channel.vi
Analog Input Timing Signals
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.
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:
1/sample period = sample rate
÷
200
RTSI 7
20 MHz
Timebase
Onboard
Clock
PFI 0–9,
RTSI 0–6
Onboard
Clock
ai/SampleClock
Timebase
ai/SampleClock
Ctr0InternalOutput
PFI 0–9,
RTSI 0–6
Divisor
Master
Timebase
Onboard
Clock
Divisor
ai/ConvertClock
Timebase
PFI 0–9,
RTSI 0–6
Ctr0InternalOutput
ai/Convert
Clock
÷
÷