Advantech iDAQ-934, User Manual

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iDAQ-934_964 User Manual 28
3.5.2 Instant Digital Input Acquisition
With instant digital input acquisition, the software controls the sample timing. Each
time the software sends a “read instant digital input sample” command, the state of all
digital input channels is sampled as shown in Figure 3.26.
Figure 3.26 Instant digital input acquisition
3.5.3 Buffered Digital Input Acquisition
With buffered digital input acquisition, the sample rate and the duration of the acquisi -
tion is controlled by hardware timing signals. All samples are stored in the buffer
memory before sending back to the host computer as shown in Figure 3.27.
Figure 3.27 Buffered digital input acquisition