Capture or Generate Hundreds of Millions of Samples Using PC Memory

Temecula, Calif.---CWAV announces the addition of the USBee ZX Digital Test Pod to the USBee product family. The USBee ZX Digital Test Pod is a high performance USB High-Speed based pod that provides an assortment of digital test and control functions, such as Logic Analyzer, Signal Generator, Data Logger, Frequency Counter, Frequency Generator, Async Serial Controller and Monitor, Pulse Counter, PWM Controller, and Remote Controller functions, all in one compact and easy to use unit. Also included is the USBee ZX Tool Builder software that allows the creation of custom test tools using Visual Basic or C++.

The USBee ZX Digital Test Pod utilizes the USB High-Speed bus to turn an existing PC into a high powered Logic Analyzer or Signal Generator that can store enough samples to fill available PC memory.

"USBee ZX users are now routinely storing over 200 million samples per Logic Analyzer trace," states Tim Harvey, CWAV's Director of Marketing, "which allows visibility into an embedded design that was previously only available on dedicated test equipment costing tens of thousands of dollars. Since the USBee ZX pod can generate hundred-million-sample waveforms as well, it opens the door to a type of control and analysis that was not cost feasible before for many embedded developers."

CWAV has designed the USBee ZX system to take advantage of already existing PC resources. The USBee ZX pod streams data over the High-Speed USB bus to and from the PC, allowing the PC to perform all of the triggering and data storing. This makes possible an affordable USBee ZX, while pushing the sample storage capabilities orders of magnitudes beyond that of traditional dedicated logic analyzers or signal generators. The USBee ZX Digital Test Pod can utilize available PC memory as the sample buffer, allowing selectable sample depths from one to many hundreds of millions of samples.

The USBee ZX Digital Test Pod can capture and generate samples up to a maximum of 24 million samples per second depending on the PC configuration. The USBee ZX Auto-Calibration feature automatically reduces the sample rate to ensure accurate and reliable timing, even on systems with slower processor and USB bus speeds.

Unlike other PC-based digital test equipment, the USBee ZX Digital Test Pod provides many different test and control capabilities depending on the software that is run on the PC. The software for the USBee ZX is provided for free at www.cwav.com and will run in demonstration mode with no USBee ZX Pod attached to the PC. The USBee ZX is priced at $895 USD and can be purchased directly from http://www.cwav.com.

For additional information, please contact CWAV by e-mail at info@cwav.com, or by mail at: CWAV, PO Box 892661, Temecula, Calif. 92589. Phone: (909) 693-3065. On-line. eeProductCenter's Alex Mendelsohn Says ...

The 480-Mbit/s speed of Universal Serial Bus v2.0 (over USB v1.1, the so-called Full Speed version) really proves its worth in CWAV's USBee ZX product. Kudos to CWAV for comprehending that USB is a quick and dirty way to leverage communications with a lab PC.

With this product, CWAV joins a handful of vendors that supply PC-hosted USB-connected test-and-measurement gear. The closest competitive product----at least from the logic analysis point of view----is Saelig's (Fairport, New York) ANT8 logic analyzer (reviewed previously at ChipCenter). It sells for less than $200. Saelig offers a 16-channel version of this instrument, too, at about $300.

The USB-powered ANT8 and ANT16 pods are powered solely from a PC's USB port. The ANT8, for example, samples eight channels (3072 samples deep) at a screaming 500-MHz sampling speed. The matchbox-sized ANT8 runs on any recent version of Windows, and its software features simple and complex triggering. The ANT8's captured traces can be viewed on-screen, or they can be saved as text or .csv files.

Windows Wares

Not mentioned in CWAV's press release is the fact that this slower product (compared to Saelig's ANT8 and ANT16 pods) also uses Windows. Communication with the PC uses USB, but Windows is where all the action takes place.

Unlike Saelig's logic analyzer-only pods, CWAV's products can adapt to perform more instrumentation functions---although logic analysis isn't as fast as Saelig's dedicated pods. "You pays yer money and takes yer choice."

Anyway, CWAV's USBee ZX runs on any suitable Windows 98, Windows 2000, or Windows XP PC. The platform must run a Pentium (or later) microprocessor, and have at least one USB port. It will also need at least 32 Mbytes of RAM, and about 25 Megs of free disk space to house the executables.

In that environment, a USBee ZX system is also quite expandable (more on this in a moment). Moreover, no separate power supply for the pod (or multiple pods) is required, and the PC's memory serves as a big sample buffer. These two factors keep the cost of this product very reasonable.

Up to 512 Channels

Here's the scoop on expansion. Need more I/O or signal generation capability? All you need do to get that is add USBee ZX pods. It's that easy to get additional channels and features. You can actually build a test system with as many as 512 channels!

In use, the free software modules that CWAV supplies from its Web site tailors your PC for the specific task at hand. You can choose to use CWAV's canned Windows software, but you can also roll your own USBee ZX atmosphere using the company's Toolbuilder application.

Source code libraries, drivers, and DLLs are included with Toolbuilder. Using it, you can write your own VisualBASIC or C applications to control and monitor signal pins on USBee ZX pods. The pod's header lines act as an 8-bit data bus, with Read/Write and trigger signals, and a clock. Using Toolbuilder's libraries and source code you can do byte-wide reads and writes to these signal lines.

Four modes of data transfers are also possible. You can choose logic analysis or signal generator capabilities, or employ one of two bit-banging modes. The first ensures flexibility for the eight signal lines. The second mode supports higher transfer rates. In the high-speed mode, you can also specify the clock rate. Available sample rates are 1-MHz, 3-MHz, 6-MHz, 12-MHz, or 24-MHz. For slower rates you can use the bi-directional mode.

Software Morphing

As mentioned, CWAV's out-of-the-box software morphs one or more of these pods into any of the instruments called out in the company's press release. The logic analyzer software, which includes an I²C bus decoder, operates at any of the above-noted sample rates (the maximum rate is dependent on your PC), providing a sample depth of 1 million samples. You can also enable four trigger states, using any of eight signals.

As you'd expect in a PC tool, you can also save and print captured data and settings. You can then use your files to load the system's signal generator function in order to playback captured signals. For its part, the signal generator is the counterpart of the analyzer. Its eight channels can develop signals at the same PC-dependent sample rates as in Capture mode.

Speaking of I²C, CWAV's system also lets you create and generate I²C bus transactions to any device on the bus. The USBee acts as the bus master running from scripts that you build. It can generate all requisite clocking and data, and can read received data and ACK status into a log file that's useful for post-processing and subsequent analysis.

Using the I²C tools, you can also generate scripts to generate single or multiple IC transactions, with custom Start, Stop, and ACK positioning within a transaction. The files store your settings, read data (from a device), start and stop tokens, and ACK levels during ACK bit times.

Toggling I/O Lines Graphically

For purely digital work, CWAV's USBee Remote Controller module also lets you toggle any of a pod's eight output signals. A simple Windows interface, like the one shown here, gives you the ability to quickly develop a stimulus pattern.

Click for full-size Controller screen image

Similarly, the USBee Data logger module lets you log digital levels of a pod's eight input signals, but over longer periods. In this mode, you write to a file on the PC in a variety of formats. Once grabbed, you can then view your data or post-process it using common Windows programs such as Excel spreadsheets. Sample rates can extend from 250-ms/sample to 300-s/sample.

An adjunct from CWAV is its USB Design Guide. These docs can help you build the same features contained in a USBee Test Pod into your own board-level design. Your hardware will then work with all USBee software modules, including any you custom-craft under Toolbuilder.

The USBee pod can be used to develop early prototypes and software, and then, when your design is finalized, you can use the Design Guide to generate circuits and board layouts.

The Design Guide includes schematics, bills of materials, suggested board layouts, and manufacturing resources. Using the guide, you should be able to rapidly develop applications such as an SPI or I²C controller, or perhaps an FPGA programmer, FIFO interface, or JTAG interface.

USBee Freebies

Lastly, if you're interested in this product line, you can download any of the software modules mentioned in CWAV's press statement, and run these executables on your PC---without ever having to buy or hook up one of CWAV's hardware pods. In a demo mode, you can then examine all the hooks and features of each module, before plunking down any cash for the USBee ZX Digital Test Pod itself.