Chapter 2
NI 5450 Overview
NI PXIe-5450 User Manual
2-80
ni.com
Trigger Timing
The following figure shows the relationship between Start trigger and the
waveform output. t
s1
is the required pulse width on the Start trigger signal.
t
s2
is the delay from the Start trigger to the waveform output. Refer to the
NI 5450 specifications for more information about these timing parameters.
The NI 5450 also allows you to export signals to trigger other devices based
on the waveform output of the signal generator. The exported Start trigger
Marker event can be exported from the signal generator to signal other
devices that waveform generation has started. NI-FGEN refers to the
exported Start trigger as the Out Start trigger.
The exported Start Trigger event is a slightly delayed version of the Start
trigger used for waveform generation. It is guaranteed to be at least 150 ns
wide. The preceding figure also shows the relationship between Start
trigger and the exported Start trigger. t
s3
is the delay between the Start
trigger and the time the device generates the exported Start trigger. t
s4
is the
pulse width of the exported Start trigger signal.
Filtering Effects
The delay from the time at which the device receives a trigger to the time
at which the analog output signal is generated increases if the digital and/or
analog filters in the Analog Output path are enabled. In the case of digital
filtering, delay also increases with increase in interpolation. Enabling the
onboard signal processing block can also introduce delay.
Note
The digital filter for the signal generator is inside the FPGA, before the Analog
Output path.
