Test Automation with NI X Series

1. What Is Test Automation?
2. Addressing Test Automation Needs with Data Acquisition
3. X Series for Test Automation
4. NI TestStand
5. Next Steps

What Is Test Automation?

Test automation is the use of software to automate a test that was previously performed manually or using multiple instruments. Examples of automated tests include stimulus and response testing, product verification, and accelerated life testing (ALT). Many test automation systems have a need to record data, use high-channel counts, or integrate analog I/O and digital I/O.

Addressing Test Automation Needs with Data Acquisition

Data acquisition meets many test automation challenges. One benefit of using data acquisition for test automation systems is that it is extremely easy to record and analyze data acquired with a data acquisition system. With Express VIs such as the DAQ Assistant and Write to Measurement File, you can quickly acquire and record your measurement readings. Figure 1 shows an example of the block diagram code needed to acquire and record the data from two analog inputs.

Figure 1. Block Diagram Code for Acquiring and Recording Data

National Instruments provides many ways for you to both record and view your test automation data. You can choose from several methods to save your data including comma-separated values (CSV) , Microsoft Excel, or Technical Data Management Streaming (TDMS). Saving data as a TDMS file has many benefits. You can view TDMS files in NI LabVIEW software and in separate applications such as NI DIAdem and Microsoft Excel. In addition, TDMS files have fast read/write rates and can store meta-information about your data such as date, time, and so on. Figure 2 shows the data from two analog signals in the TDMS File Viewer.

Figure 2. With the TDMS File Viewer, you can easily record and view test automation data.

Data acquisition devices also provide extremely high-channel counts and the ability to integrate multiple signals into one measurement task. With X Series devices, you can synchronize channels from multiple cards and read them within the same task. Figure 3 shows how you can use different types of analog inputs in the same NI-DAQmx task.

Figure 3. Use an NI-DAQmx task with several types of virtual channels.

By using multifunction data acquisition devices, you can easily integrate and implement multiple subsystems including analog input (AI), analog output (AO), digital input/output (DIO), and counters. With NI-DAQmx and LabVIEW, you can quickly and easily create test automation systems using several types of inputs and outputs. Figure 4 shows how easy it is to begin acquiring and generating data using multiple subsystems.

Figure 4. This block diagram example shows parallel AI, AO, DIO, and counters using the DAQ Assistant.

X Series for Test Automation

X Series devices are ideal for many test automation applications. They address the need for high-channel counts by providing up to 32 analog inputs, four analog outputs, and 48 digital I/O lines. In addition, X Series devices offer tight synchronization and timing of AI, AO, and DIO with NI-STC3 timing and synchronization technology. This technology also provides four enhanced counters and an improved 100 MHz timebase.

X Series devices are available for USB, PCI Express, and PXI Express. PXI (PCI eXtensions for Instrumentation) is an open, PC-based platform for test and control. PXI Express, the latest iteration of the PXI platform, offers up to 2 GB/s dedicated per-slot bandwidth and the industry’s highest-performance timing and synchronization capabilities. 

You can synchronize multiple USB X Series devices by connecting their PFI lines with external wiring and exporting sample clocks. For improved performance and ease of use, you can use PCI Express and PXI Express X Series devices and multidevice tasks, which are a simplified programming method in NI-DAQmx for acquiring data from two or more X Series devices. You can synchronize PCI Express X Series devices with a Real-Time System Integration (RTSI) cable and PXI Express X Series over the PXI backplane. With more than 1,500 modules for the PXI platform, PXI Express gives you the ability to easily upgrade your test automation systems.

With X Series and LabVIEW, you can create custom graphical user interfaces and sophisticated test sequences. LabVIEW is a graphical programming language that helps you quickly develop advanced test and measurement software. With LabVIEW and the multithreaded NI-DAQmx driver, you can easily develop test automation software that takes advantage of multicore CPUs. You can develop applications using NI-DAQmx with C, C++, C#, Visual Basic .NET, and LabVIEW. PCI Express and PXI Express X Series devices require NI-DAQmx driver software Version 9.0 or later, and USB X Series devices require NI-DAQmx Version 9.2 or later.

NI TestStand

X Series devices integrate well with NI TestStand, which is ready-to-run test management software designed to help you develop automated test and validation systems faster. You can use this software for device characterization, validation testing, and manufacturing testing. NI TestStand was designed to simplify and accelerate complex sequence development, increase code and test system reusability and maintenance, and improve test system execution performance.

Figure 5. NI TestStand Sequence Editor

Next Steps

Explore the X Series Test Automation Starter System 

Read NI test automation success stories

View the X Series for Test Automation webcast

See X Series specifications and pricing 

3 Ratings | 3.67 out of 5

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