National Instruments 5411 - Manual (Page 38)

Chapter 4 Arb Operation
© National Instruments Corporation 4-13 DAQArb 5411 User Manual
Figure 4-9. Single Trigger Mode for Arb Mode
Note: You can settle to a predefined state by making the last stage emulate that
state.
• DDS mode—After the DAQArb 5411 receives a trigger, the
waveform generation starts from the first stage and continues
through to the last stage. The last stage is generated repeatedly until
the waveform generation is stopped. Figure 4-10 illustrates a single
trigger mode of operation for DDS waveform generation mode.
Figure 4-10. Single Trigger Mode for DDS Mode
Assume that one cycle of a sine wave is stored in the DDS lookup
memory. For stage 1, f1 specifies the sine frequency to be
generated for time
∆
T1, f2 and
∆
T2 for stage 2, and so on. If there
are four stages in the staging list, then f4 will be generated
continuously until the waveform generation is stopped.
Continuous Trigger Mode
The waveform you describe in the staging list is generated infinitely by
recycling through all the staging list. After a trigger is received, the
waveform generation starts from the first stage and continues through
to the last stage. After the last stage is completed, the waveform
generation loops back to the start of the first stage and continues until
it is stopped. Only one trigger is required to start the waveform
generation.
Start Trigger
End of All Stages Last Stage Generated Continuously Until Stopped
Start Trigger
Last Stage Generated
Continuously Until Stopped
End of All Stages
f1,
∆
T1 f2,
∆
T2 f3,
∆
T3 f4