Chapter 4 Arb Operation
DAQArb 5411 User Manual 4-16
©
National Instruments Corporation
Figure 4-14. Burst Trigger Mode for Arb Mode
• DDS mode—Figure 4-15 illustrates a burst trigger mode of
operation for DDS mode. The switching from one stage to the other
stage is phase continuous. In this mode the time instruction is not
used. The trigger paces the waveform generation from one
frequency to the other.
Figure 4-15. Burst Trigger Mode for DDS Mode
Marker Output Signal
A marker is equivalent to a trigger output signal and it is available on a
separate pin in the digital I/O connector. You can define this TTL level
trigger output signal at any position in the waveform buffer. You can
place a marker in every stage; however, only one marker per stage is
allowed.
You can specify a marker by giving an offset count (in number of
samples) from the start of the waveform bu ff er spe c ifi ed b y t h e stag e.
If the offset is out of range of the number of samples in that stage, the
marker will not appear at the output. If the buffer is looped multiple
times in a stage, the marker will be generated that many times.
Start Trigger Start Trigger
End
of Stage 1
Start Trigger
End
of Stage 2
End
of Stage 3
Start Triggers
End
of Stage 1
Continues In This
Way of Triggering
Until Stopped
End of All Sta
g
es
f1 f2 f3 f4
Start Trigger Start Trigger Start Trigger Start Trigger Start Trigger
f1