User`s guide

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Operation Theory
4.2.2.1 Trigger Modes
Post-Trigger Generation
Use post trigger when you want to perform DA waveform right after a
trigger event occurs. In this trigger mode DLY1_Counter is not used and
you don’t need to specify it. Figure 23 shows a single waveform generated
right after a trigger signal is detected. The trigger signal could come from a
software command, an analog trigger or a digital trigger. Please refer to
section 4.5 for detailed information.
(UC _Counter=8, IC_Counter=1)
8 update counts, 1 iteration
DAWR
WFG_in_progress
O
p
eration start
Trigger
Output Waveform
0
2
4
6
3
-4
-2
4
Figure 23: Post trigger waveform generation
(Assuming the data in the data buffer are 2V, 4V, 6V, 3V, 0V, -4V, -2V, 4V)
Delay-Trigger Generation
Use delay trigger when you want to delay the waveform generation after a
trigger event. In figure 24, DA_DLY1_counter determines the delay time
from the trigger signal to the start of the waveform generation.
DLY1_counter counts down on the rising edge of its clock source after the
trigger condition is met. When the count reaches 0, the counter stops and
the DAQ-2214 starts the waveform generation. This DLY1_Counter is
16-bit’s wide and users can set the delay time in units of TIMEBASE (delay
time = DLY1_Counter/TIMEBASE) or in units of update period (delay time
DLY1_Counter * UI_counter/TIMEBASE), such that the delay time can
reach a wider range.