When you develop products that will employ a Universal Serial Bus (USB) connection, you might need to dive into the nitty-gritty analysis of bus traffic. Previously, that meant struggling through binary, hexadecimal, or other low-level information to find and then interpret transactions. No software developer or hardware engineer wants to work at that level when tools can distance them from bits and bytes.

Total Phase, a supplier of serial-bus analyzers and data-capture pods, has added USB class-level decode capabilities to its Data Center (ver 3.5) software. So, developers have access to detailed information, such as commands, addresses, descriptors, and data, which makes it easier to find and fix bugs in software. So far, the Data Center software covers USB classes for human-interface devices (HIDs) as well as mass-storage, hub, and audio USB devices. The new class-level decoding includes advanced hierarchical transaction grouping, descriptor parsing for individual transactions, and class-level filters. (The company plans to offer add more USB classes to the software.)

The free Data Center software can capture, display, and filter USB, I2C, and SPI bus information in real-time when used with the Beagle hardware protocol analyzers. You can download the software at: www.totalphase.com/categories/software/.

The Beagle USB 480 Protocol Analyzer ($US 1200) provides for complete class-level decoding, while the Beagle USB 12 analyzer ($US 400) supports only USB descriptor parsing. Total Phase also sells products such as a host adapter, programming interface, protocol analyzer, and development kit for I2C and SPI buses. Developers can find more information at: www.totalphase.com/products/.

If you work with--or plan to work with--USB-based devices, I highly recommend Jan Axelson's book, "USB Complete:The Developer's Guide," 4th edition, Lakeview Research, 2009. $54.95, ISBN: 978-1-931448-08-6. Jan also has written, "USB Mass Storage: Designing and Programming Devices and Embedded Hosts," Lakeview Research, 2006. $19.95, ISBN: 978-1-931448-04-8. The Lakeview Research Web site lists many local and national booksellers that stock these helpful books: www.lvr.com/ordering.htm.
--Jon Titus