This document starts by exploring the common features of a logic analyzer used in viewing and analyzing digital data. The article then dives into how the NI Digital Waveform Editor can be used in conjunction with NI products, such as the NI Logic Analyzer solution, to view and analyze digital waveforms in a graphical and interactive environment.
A logic analyzer is an instrument that captures the response of a digital system for use in debugging and verifying its operation. In order to capture the necessary data, logic analyzers provide the ability to trigger the start of an acquisition, whether it be through a software command or complex sequential pattern matching, as well as the ability to probe or connect to the digital system under test.
Once the data has been acquired, a logic analyzer needs to provide the users with a familiar, easy-to-use interface that allows them to quickly analyze the acquired digital data, which can sometimes be millions of samples long. At the very minimum, a logic analyzer's user interface includes the ability to simultaneously view and analyze multiple channels of digital data so that the state of the digital system can be viewed and the timing relationships between signals determined. The display on most logic analyzers allow users to pan through the acquired data and mark sections of the data for easy location later.
Recent PC-based logic analyzers allow engineers to use the familiar operating environment of their desktop computer to acquire, analyze, and present their digital data. NI offers a Logic Analyzer and Pattern Generator solution that combines interactive software with modular hardware. By leveraging the performance and flexibility of the standard PC, users can store an almost unlimited amount of acquired data to be analyzed by custom algorithms or quickly viewed with software packages, such as the NI Digital Waveform Editor. This paper takes a look at how to get started with the NI Digital Waveform Editor and some of its key features that can be used to view and analyze digital signals.
The NI Digital Waveform Editor is an interactive software tool for creating, editing and importing digital waveforms. The software provides a straightforward user interface for viewing and analyzing large numbers of digital waveforms graphically. While usually used for creating new digital waveforms with automatic fill patterns, with the NI Digital Waveform Editor you can leverage the powerful, interactive environment to display and analyze signals after acquisition. With features such as searching, bookmarks and cursors, the NI Digital Waveform Editor offers a simple but effective interface for managing digital data.
Furthermore, you can link the design and test of your digital device together by importing existing test vectors in ASCII or Value Change Dump (.VCD) file formats from popular spreadsheet and digital simulation packages. This allows you to use a single environment for viewing data not only acquired from your device under test but also from the simulation phases of your product.
The NI Logic Analyzer solution combines an NI 100 MHz Digital Waveform Generator/Analyzer instrument with NI SignalExpress and the NI Digital Waveform Editor application software. This PC-Based logic analyzer solution allows the full power of the computer to be used to perform complex analysis, data logging, and report generation. SignalExpress is a software environment that allows you to interactively create analysis and acquisition programs without requiring any knowledge of programming. Once data is acquired with SignalExpress, you can view, analyze, and edit your saved digital data in the NI Digital Waveform Editor by navigating to Tools » Digital Waveform Editor... in the SignalExpress menu. Once the NI Digital Waveform Editor screen has launched, you can uses the features discussed below to open and analyze your data.
a. Import Acquired or Simulated Test Vectors
b. Cursors
c. Zoom Tools
d. Bookmarks
e. Search for Pattern