Wrap It Up

Wrap It Up!

This chapter has helped get you started with using LabVIEW to perform data acquisition.

We looked at the concepts of buffering and triggering. Buffering is a method for storing samples temporarily in a memory location (the buffer), and is used for fast and accurate sampling rates. Triggering is a method to initiate and/or end data acquisition dependent on a trigger signal. The trigger can come from the software or from an external signal. We also learned about digital I/O and its terminology, like "port," "line," "direction," and "state."

NI-DAQmx Tasks provide a solid model for signal measurement and generation. We discussed using MAX to create and edit tasks, referencing those tasks in LabVIEW, and generating LabVIEW configuration and examples code directly from your tasks!

Using NI-DAQmx tasks in LabVIEW is easy with the DAQmx VIsnearly all DAQ applications will only need to use the same five or six VIs. This ease of use comes from the polymorphism of the DAQmx VIs. These VIs let you acquire one point (nonbuffered AI) or a whole waveform (buffered AI) from one or multiple channels. They allow you to perform buffered I/O, hardware triggering, and disk streaming. They also allow you to read from and write to the digital lines of a DAQ device. You can read or write either a single line or a whole port (four or eight lines, depending on the DAQ device).

We also learned some advanced DAQ techniques such as timing and triggering, multi-channel acquisition, continuous acquisition, and streaming to file. We explored the interesting world of digital events and timing using counters to count digital pulses and generate pulses.