Advantech iDAQ-900 Series User Manual page 37

The start and stop of the generation are controlled by the start trigger and stop trig-
ger, respectively. When configuration is complete, the acquisition engine of the iDAQ
chassis is at standby state. After receiving a start trigger, generation becomes active
and each rising edge of the sample clock converts one analog output sample. The
generation active period lasts until a stop trigger is received, which ends the genera-
tion. This is shown in Figure 3.19.
Figure 3.19 Start and stop of the analog output waveform generation
The start and stop of generation can also be delayed in number of samples after
receiving the corresponding trigger signal. As shown in Figure 3.20, the start of gen-
eration is delayed by 3 samples after receiving a start trigger, and the stop of genera-
tion is delayed by 2 samples after receiving a stop trigger.
Figure 3.20 Start and stop of the analog output waveform generation with delay
Refer to 3.1.1 Signal Routing for possible signal routings and configurations for these
timing signals (start trigger, stop trigger, and sample clock).
Buffered analog output waveform generation has several advantages over static ana-
log output update:
The start and stop time of generation (or duration of the generation) can be pre-

cisely controlled by hardware trigger signals.
DAC conversion rate is configurable, and update rate can be much higher by

using hardware sample clock signal.
Time between samples is deterministic.

27 iDAQ-900 User Manual