The Automated Test Blog

Embedded.com recently published an article by an engineer at On Semiconductor about their use of PXI and LabVIEW for the characterization benches.  In the article, Ray Morgan describes the benefits of this system over previous approaches, saying, among other things that “the PXI platform set a new standard for semiconductor design validation, breaking many of the paradigms and constraints of previous testing methodologies”.

I found the article particularly inersting as it articulates some common challenges I’ve been seeing in semiconductor characterization that I believe PXI and LabVIEW are very well-suited to solve.  We are, in fact, seeing a major uptick in the use of these platforms in applications such as these.  Another technolgy that I believe will be important in these applications is the user-programmable FPGA.  I discussed this trend in a previous post on Protocol Aware ATE.

As I stated in my last blog post, I’m planning to discuss one of three industry trends per blog entry over the next few weeks. My 2nd trend is:

Trend#2: Increased Adoption of Parallel Processing Technologies

Multicore technology has become a standard feature in automated test systems and a necessity for today’s electronic devices that are processing unprecedented amounts of data. Software-defined instrumentation takes advantage of the latest multicore processors and high-speed bus technologies to generate, capture, analyze and process the gigabytes of data required to properly design and test electronic devices. Multicore architectures can present a challenge when used with traditional text-based programming environments that are not inherently parallel and require low-level programming techniques. However, test engineers quickly can realize the benefits of multicore technology through inherently higher level programming environments such as LabVIEW, which automatically distributes multithreaded applications across multiple computing cores for maximum performance and throughput.

Many test engineers I talk to are already experiencing the challenge of programming multicore in that, for the first time, they are not seeing an increase in test system performance when updating the PC in the system. In fact, due to the potentially slower clock rates of many multicore processors, their systems may actually run slower!

On the other hand, Alejandro Torres, senior manufacturing test engineer at Sanmina-SCI, provided an example of the potential business benefits attained by using programming tools tuned for multicore technology when he stated, “By leveraging the multicore technology in LabVIEW and the latest NI multicore PXI embedded controller, we were able to increase our test throughput by one additional workday per week. Best of all, we achieved this throughput increase by simply upgrading from a previous-generation PXI single-core embedded controller to the latest NI PXI multicore embedded controller with only minimal changes to our code.”

Another area of growth for software-defined instrumentation is the increase in system-level design tools for FPGAs. Many modular instruments now come equipped with FPGAs, including several released in the past year that offer the high-performance Xilinx Virtex-5 FPGA. These FPGA-based instruments provide test engineers with the ability to implement more complex digital signal processing at faster rates than ever before. Because software programs such as LabVIEW give test engineers the ability to program FPGAs without requiring knowledge of VHDL, the performance benefits of FPGAs are no longer limited to a subset of hardware engineers with extensive knowledge in digital design.

Next week, I’ll post on the third trend, the Expansion of Wireless and Protocol-Aware Test.

As I stated in an earlier blog post, I’m planning to discuss one of five industry trends per blog entry over the next few weeks. My 3^rd trend is:

Growing Popularity of FPGA-Enabled Instrumentation
Another area experiencing rapid expansion in the test industry is the increase in system-level tools for field-programmable gate arrays (FPGAs). FPGAs are powerful because they are inherently parallel, deterministic, and reliable and can be defined and reconfigured in software. While FPGAs are used inside many embedded designs, and even standalone instruments, users are not typically given access to reprogram them. More manufacturers are beginning to include open FPGAs on modular instruments and are giving test engineers the means in software to reprogram them according to their requirements. With this capability, test engineers can embed a custom algorithm into the device to perform in-line processing inside the FPGA or emulate part of the system that requires a real-time response. Historically, most test engineers do not have expertise to program FPGAs because they familiarity with hardware description languages like Verilog or VHDL which use low-level syntax to describe hardware behavior. New system-level tools are emerging that provide test engineers with the ability to rapidly configure FPGAs without writing low-level HDL code. LabVIEW, for example, can target onboard FPGAs and synthesize the necessary hardware directly from a graphical LabVIEW program, dramatically reducing the complexity of the code development. I’ve been amazed at the things our customers, who are often domain exprerts, but not experts in hardware design, have been able to accomplish with LabVIEW FPGA.  Examples include testing RFID devices performing bit-error-rate testing (BERT) of military communication protocols.

This is the time of the year where you see a lot of people making their predictions on the hot trends in 2008 and beyond. Of course, as the old joke goes, predictions are hard, especially the ones about the future. But, anyway, here goes.

Since my company serves a very broad and diverse set of customers, I get the opportunity to talk to electronics designers and test engineers in applications ranging from medical devices manufacturing to high energy physics experimentation. The common thread that continues to resurface is that they are each facing the challenge of testing increasingly complicated designs with shrinking timelines and budgets. These demands have led to five major trends that I believe will significantly influence the Test and Measurement industry over the next three years. Instead of blogging them all here today, I will share one per entry over the next few weeks. The first trend is:

Increased Use of Multicore/Parallel Test Systems
Processor manufactures, such as Intel and AMD, have started developing processors with multiple cores on a single chip to continue realizing performance gains without increasing clock rates (otherwise, PCs would soon be doubling as ovens). With multicore processors, test engineers can develop automated test applications capable of achieving the highest possible throughput through parallel processing. However, this is not as easy as it sounds. Check out a few articles describing the challenge of multicore programming:
• The Free Lunch Is Over : A Fundamental Turn Toward Concurrency in Software
• Dearth of tools could stall multicore onslaught

The summary is that programming multicore puts fundamentally different requirements on software, and most of today’s software tools don’t have very good native and scalable ways to deal with it. Sure, you can create a multithreaded program in C and synchronize it using textual constructs, but try scaling that to 80 cores (the number Intel plans to demonstrate by 2011). Graphical languages, however, such as NI LabVIEW, are able to elegantly represent parallel concepts; in fact, LabVIEW already automatically scales programs to multiple cores and has demonstrated significant performance improvements over single core processors.

Multicore technology is not only an opportunity to increase performance, but as Herb Sutter describes in the ‘Free Lunch’ article above, the performance improvement we have taken for granted with each generation of processor may no longer hold if our programming environment does not take advantage of the parallelism.

Last week was National Instrument’s annual user conference, NI Week. It has become more of a whirlwind every year, and this year set a new bar: over 2500 customers, plus members of the trade press, investors, university professors, partners, and NI employees. I’m still digesting all the feedback and takeaways, but here was my overriding impression: over the past few years, the sophistication of applications that our users have accomplished with NI tools has grown remarkably. I recall judging our application paper contest just a few years ago in the communication category and all the applications submitted were fairly straightforward GPIB-controlled test applications. Today, NI hardware and software are being used in research labs to prototype the latest communication standards, in RF chip validation testers, and in high volume production test of wireless devices. During the NI Week keynotes, we showed leading edge applications of virtual instrumentation, including a ‘mind controlled wheelchair’, a Boeing 787 audio flyover test system, multichannel video streaming, and a cryogenic medical device – all applications of LabVIEW. It really is amazing what our users our accomplishing with our tools.

I am hearing increasingly from customers and other vendors in test and measurement about the need for “Open Analysis”. The need is driven by the increasingly diverse set of applications and thus measurement requirements driven by, among other things, macro trends outlined in the book The Long Tail. As communication standards continue to proliferate, and the pace of change increases, users need tools that can adapt just as rapidly to their changing measurement needs. Instrumentation vendors such as Tektronix, for example, are increasingly offering options for users to plug in third party analysis tools, or export their data to analysis environments for custom processing. Tek’s OpenChoice is “a collection of software libraries, utilities, samples, industry-standard protocols and interfaces”. An example of OpenChoice software is SignalExpress Tektronix Edition, which is used to automate Tektronix instruments and bring data into and open, PC-based environment for further analysis. Tektronix AEs, third parties, or customers themselves can add in their own custom analysis to meet their specific application needs.