I have worked with serial communications from slow 110 bits/second current loops up to CAN bus communications and thus appreciate how much time a protocol analyzer can save.  Working at even higher speeds must tax engineers who rely solely on a scope or logic analyzer without protocol-analysis tools.

Anyone who develops a product that will use a USB 3.0 connection might need to monitor, track, and analyze USB communications to ensure they comply with the latest USB standards. Recently, Total Phase introduced the Beagle USB 5000 SuperSpeed Protocol Analyzer (TP320910) that provides real-time interactive capture and analysis of USB 3.0 and USB 2.0 (as high as 5 Gbits/second) bus operations. The company's free Data Center protocol-analysis software runs under the Windows, Linux, and Mac OS X operating systems. (People often refer to the USB 3.0 specifications as "SuperSpeed USB.")

The software lets product designers and engineers observe class-level decoding that converts protocol-level information (basic bytes) into more useful USB class-level commands and instructions such as Request Sense, Read Capacity, Data Transport, and so on. Individual device classes cover products such as printers, audio devices, cameras, mass-storage equipment, human-interface devices, and others. So, if you have a new USB 3.0-based communication device, for example, you can view the commands and traffic in a format that make sense to you and your device. The Beagle USB 5000 offers both a protocol-level and a class-level view of USB information.

Although the Beagle 5000 specifications note a memory capacity of 2 Gbytes, the instrument streams data to a host PC, so it can capture much more bus information. Because USB traffic generally occurs in bursts, the host PC can "catch up" to data stored locally in the instrument. If you will use other analysis instruments, you can use the Beagle 5000 triggers and digital I/O lines to synchronize data capture with specific bus transactions or external-device trigger signals.

Learn more about the Beagle USB 5000 at: www.totalphase.com/products/beagle_usb5000.  A standard analyzer will cost $US 5000 and customers can purchase two upgrade options: Option A for simultaneous USB 3.0/2.0 monitoring and

advanced triggers (software upgrade only), and Option B, which increases the buffer to 4 Gbytes and includes current/voltage measurements (hardware upgrade, available early 2011).

Find the USB Implementers Forum at: www.usb.org/about.  This group establishes the USB standards, runs compliance workshops, and develops USB tests. --Jon Titus

While at the Embedded Systems Conference two handy tools caught my eye. First, the Mobidapter, an SD-to-USB adapter from Saelig and second the Micro Computer Control i2cStick that gives you a connection between a USB port and an I2C bus.

Years ago, true in-circuit emulator (ICE) pods provided bonded-out processor chips that gave designers access to internal chip signals. Most microcontrollers now support on-chip debug, background debug mode, or JTAG-like interface that simplifies program development and debugging, and usually accommodates programming flash memory from a host computer.

During a conversation about motor controllers, Jonathan Guy, the software and systems manager at Texas Instruments' Stellaris group mentioned an interesting debug technique that links processor code to real-world events. Instead of using software-debug tools to "watch" a variable, Jonathan suggested sending the value to a digital-to-analog converter (DAC) via an SPI or I2C port. That approach makes a lot of sense because those I/O ports require few pins and they can transfer information in near-real-time. And, you can view the output of the DAC along with digital and analog signals from elsewhere in your system on a scope. If you need to watch several variables, you can buy 4-channel SPI or I2C DACs.