Using An Internal Source; Using An External Source; Routing Ai Convert Clock Signal To An Output Terminal; Using A Delay From Sample Clock To Convert Clock - National Instruments NI 6221 User Manual

Chapter 4 Analog Input
M Series User Manual

Using an Internal Source

One of the following internal signals can drive ai/ConvertClock:
• AI Convert Clock Timebase (divided down)
• Counter n Internal Output
A programmable internal counter divides down the AI Convert Clock
Timebase to generate ai/ConvertClock. The counter is started by
ai/SampleClock and continues to count down to zero, produces an
ai/ConvertClock, reloads itself, and repeats the process until the sample is
finished. It then reloads itself in preparation for the next ai/SampleClock
pulse.

Using an External Source

Use one of the following external signals as the source of ai/ConvertClock:
• PFI <0..15>
• RTSI <0..7>
• PXI_STAR
• Analog Comparison Event (an analog trigger)
Routing AI Convert Clock Signal to an Output
Terminal
You can route ai/ConvertClock (as an active low signal) out to any
PFI <0..15> or RTSI <0..7> terminal.
All PFI terminals are configured as inputs by default.

Using a Delay from Sample Clock to Convert Clock

When using an internally generated ai/ConvertClock, you also can specify
a configurable delay from ai/SampleClock to the first ai/ConvertClock
pulse within the sample. By default, this delay is three ticks of
ai/ConvertClockTimebase.
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