ADLINK PXI-2208 - Manual (Page 70)

58 Operation Theory
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 ignored and not be specified. Figure 4-15 shows a single
waveform generated right after a trigger signal is detected and
assuming the data in the data buffer are 2V, 4V, 6V, 3V, 0V, -
4V, -2V, and 4V. The trigger signal could come from a software
command, an analog trigger or a digital trigger. Refer to section
4.5 for detailed information.
Figure 4-15: Post Trigger Waveform Generation
Delay-Trigger Generation
Use delay trigger when you want to delay the waveform gener-
ation after a trigger event. In Table 4-16, DA_DLY1_counter
determines the delay time from the trigger signal to the start of
the waveform generation, assuming the data in the data buffer
are 2V, 4V, 6V, 3V, 0V, -4V, -2V, and 4V. DLY1_counter
counts down on the rising edge of its clock source after the trig-
ger condition is met. When the count reaches 0, the counter
stops and the DAQ-/DAQe-/PXI-2204/2205/2206/2208 card
starts the waveform generation. This DLY1_Counter is 16-bit
wide and you 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),
so the delay time can reach a wider range.
(UC _Counter=8, IC_Counter=1)
8 update counts, 1 iteration
DAWR
WFG_in_progress
Operation start
Trigger
Output Waveform
0
2
4
6
3
-4
-2
4