Test Data Out

Defects on High-Speed Memory – Part 2

Last month, we saw how defects on memory data lines can cause a system to fail, and yet escape detection by the system boot loader or BIOS. Let’s examine this in more technical detail.

High-Speed Non-Intrusive Board Test | PCI, QPI

Non-intrusive testing according to a dictionary means: “testing that is transparent to the [software] under test, i.e. does not change its timing or processing characteristics. Non-intrusive testing usually involves additional hardware that collects timing or processing  information and processes that information on other platforms”.

Non-intrusive board test. Does such a thing really exist? If by the phrase you mean a test methodology that has no physical effect on the unit being tested, then the answer is yes; it definitely exists.  Non-intrusive board test (NBT) uses soft access to onboard embedded instruments and test technologies like BIST to test circuit boards. All it needs is a single point of connection – the rest is software. Software to access, drive and collect data from test routines, and then to make sense of it all for the user. Almost everything from the processor out can be driven and tested without physical access to anything but the processer itself. And the higher the speed, the more crucial this becomes. Physically probing signals above 5 GHz is not a good thing.

Defect Coverage | Non-intrusive Board Test eBook

Think about it. Test without touching a single bus with probles. Test without expensive fixtures. Soft access through existing board connectors and JTAG ports to create virtual, re-programmable test points. Wherever you want them. Whenever you want them. Clearly, 'mechanical test' is the way of the past and a software-driven approach is the future. But it's here and now. 

This is non-intrusive board test, or NBT, becuase it really does not contaminate your tests results in any physical way. And that is important as speed continues to increase and physical access goes away. Instead, non-intrusive test relies solely on a combination of embedded instrumentation, onboard test structures and tools that access the test object through software or 'soft access'.

Learn all about non-intrusive board test directly from Adam Ley, Chief Technologist at ASSET InterTech, provider of the soft access ScanWorks platform for board debug, validation and test, by registering for our eBook, "Defect Coverage | Non-intrusive Board Test eBook".

PXI meets embedded instrumentation

PXI is a hardware-based modular test standard. If PXI users want to add test capabilities, they have to add another hardware module to a PXI card cage. Now that’s changed with the new ScanWorks® PXI-1000 controller. Let’s say you have ScanWorks and a PXI-1000 controller and you’re doing boundary-scan test (IEEE 1149.1 and 1149.6), but you want to detect a broader spectrum of structural defects so you add another embedded instrumentation test technology like IJTAG (IEEE P1687 Internal JTAG). No, you won’t need another PXI-1000 controller. You just expand the capabilities of ScanWorks and the PXI-1000 that’s already in your PXI chassis takes care of the rest. PXI, meet embedded instrumentation.

Structural Defects on High-Speed Serial I/O

Shorts and open circuits on high-speed serdes buses, such as PCI Express, may have subtle and difficult-to-diagnose effects on system performance. In other words, you might not know about them until customers start complaining and you get warranty returns. What kind of effects are these, and how are they prevented?

Diminishing ICT Test Coverage

Our chief technologist of non-intrusive board test, Adam Ley, recently published an e-Book on solving the problem of diminishing test coverage from In-Circuit Test (ICT). What’s the key take-away from this publication?

e-Book: Solving the Problem of Diminishing Test Coverage from In-Circuit Test (ICT)

Are you investing new capital on an old test strategy that is centered around in-circuit test but getting less of a return on that money?  Much has changed in the decades since ICT was introduced.  These changes are covered in Adam Ley's e-Book: Solving the Problems of Diminishing Test Coverage from In-Circuit Test (ICT).  While test access and test coverage at ICT are diminishing, new standards and techniques continue to emerge to fill the void.

How to eliminate throw-away code

It’s all about time management in product development. Nowhere is time management more critical than during board bring-up, when the bare metal software needs to be integrated with the new hardware platform. The problem is a chicken-or-egg issue. You need the hardware to develop the software. To have functioning hardware, you need some bare-metal software. What happens then?

Adaptive Equalization - Part 2

In a previous blog, I described how fixed and adaptive equalization techniques are used within chips to ensure signal integrity even in adverse system conditions. Why is it important to tune these parameters within a chip?

Single-bit Memory Errors

Ever wonder if a stray cosmic ray or alpha particle might double your bank account, due to an undetected RAM error?