Does this ever happen to you? You're at a cocktail party, let's say, and someone asks you what you do for a living and you know that you'll never be able to explain it in terms they will understand. For that matter, does your mother even know what you do for a living? How about your spouse/spousal equivalent/significant other? That's the question that Jack wrestles with this week in “Can't Get No Respect.” Based on the result so far in this week's poll, most spouses or spousal equivalents have only a vague idea about the embedded world at best.Now on to the rest of what's new on Embedded.com.
In “Incorporating Server Characteristics Into Embedded Design” Bernie Cole says that as tough as real-time development is, it gets even worse when you're dealing with net-centric systems. You have to achieve deterministic behavior across a network. In this column he speculates on potential solutions.
Embedded systems rely on all sorts of sensors because they enable software to detect what is happening in the real world. Temperature sensors are one of the most commonly used kinds of sensors, and they come in a variety of flavors. In ” Temperature Measurement Techniques” Stuart Ball surveys various kinds of temperature sensors and describes how to interface them to a processor.
If it happens on the desktop, sooner or later it will reach embedded systems. This rule of thumb is being borne out with Web services, programmable components that provide a service and are accessible over the Internet. At the enterprise level, Web services, such as .NET, Sun's ONE, HP's e-services, and IBM's Websphere, are rapidly becoming the native language of business applications. Their penetration into the embedded realm won't be far behind according to John Canosa in “Introduction to Web Services.”
ISO 9000 promoters claim quality can be generalized across multiple industries. Even though ISO 9000 compliance is mandated by many government agencies for their suppliers, not everyone agrees that it improves quality. My brother-in-law is an ISO 9000 consultant. His point of view may not be completely in compliance with Niall Murphy's. In “A Question of Quality” Niall offers a skeptical look at the ubiquitous standard and examines some of the controversy surrounding it.
In “Whither Embedded?” Michael Barr ponders the age-old question, “What is an embedded system?” We know what it is not: it's not a desktop computer. But the range of embedded systems is so broad and varied and is distributed among so many vertical markets, one has to ask what do diverse embedded systems share in common. Michael argues that it is the skill set of embedded systems developers that provides that commonality because it is transferable from vertical market to vertical market.
If you've been missing Jack Crenshaw recently, it's because he's been moving his household from Florida to Arizona. Everything that could go wrong did during the move, and it has added names to Jack's list of Good Guys and Bad Guys. You might be surprised to see who winds up where. One thing's for sure: Jack still misses his Kaypro. Read the excruciating details in “Bad Trip.”
While symbolic constants will help your code, you can overuse them, says Dan Saks. In “Symbolic Constant Expressions,” he says that symbolic constant expressions can be just as useful, but without all the clutter.
“Can Hardware Be Trusted?” asks Jack Ganssle. Conventional wisdom says that while software may be suspect, hardware is perfect. Well, perfect except for the occasional glitch. Our long-held assumptions about reliable and deterministic hardware may not be valid much longer, and Jack blames it all on cosmic rays.
Embedded systems are noted for economy of design. Things aren't luxurious “inside the box,” and you won't find many expensive communications solutions there. One method for low-cost, low-speed communication is I2C, which we covered August. Another option is the serial peripheral interface. This month David Kalinsky and Roee Kalinsky explain how it works in “Beginner’s Corner.”
New at embedded download central is a demo of CodeScape, a set of hardware-assisted real-time tools for high-performance embedded systems and DSPs. CodeScape includes compilers, source-level debuggers, code profilers, cycle-accurate processor simulators, real-time bus monitors, and an integrated development environment. These tools are for Hitachi and STMicroelectronics' SuperH-based processors and Imagination Technologies' META processor architecture.
And last, but definitely not least, don't forget to sign up for the Embedded Systems Conference scheduled for March 12 through 16 at San Francisco's Moscone Convention Center. The keynote speaker will be Nobel Prize winning physicist Murray Gell-Mann. You can register here for the biggest embedded event of the year.
Those of you who plan to drive to San Francisco can find parking information here, complete with rates and actual photos of parking lots and garages. If you don't want to try to park in the city, you can always leave the driving to BART or Caltrain.