Chapter 5 Analog Output
NI USB-621x User Manual 5-8 ni.com
AO Sample Clock Signal
Use the AO Sample Clock (ao/SampleClock) signal to initiate AO samples.
Each sample updates the outputs of all of the DACs. You can specify an
internal or external source for AO Sample Clock. You also can specify
whether the DAC update begins on the rising edge or falling edge of
AO Sample Clock.
Using an Internal Source
One of the following internal signals can drive AO Sample Clock:
• AO Sample Clock Timebase (divided down)
•Counter n Internal Output
A programmable internal counter divides down the AO Sample Clock
Timebase signal.
Using an External Source
Use any input PFI line as the source of AO Sample Clock.
Routing AO Sample Clock to an Output Terminal
You can route AO Sample Clock (as an active low signal) out to any output
PFI terminal.
Other Timing Requirements
A counter on your device internally generates AO Sample Clock unless you
select an external source. AO Start Trigger starts the counter and either the
software or hardware can stop it once a finite generation completes. When
using an internally generated AO Sample Clock, you also can specify a
configurable delay from AO Start Trigger to the first AO Sample Clock
pulse. By default, this delay is two ticks of AO Sample Clock Timebase.
To Next Page
Loading...
Need help?
General
