Using UPnP to Respond to Inquiries
by Edward Steinfeld

UPnP is an architecture of peer-to-peer networking of intelligent machines, appliances, wireless devices, and computers of varying form factors. Edward shows us that UPnP succeeds in answering such questions as what machines are on the Internet, how are operations controlled, and will the machines notify when they have a significant event? With the power of UPnP and the right tools, it can only be easy times ahead.

May 2001

Part 2: All of the Details
by Walter Krawec

Picking up where he left off last month, Walter now takes on the task of building the full file manager. Taking us through the ins and outs of managing the development of projects on the processor and then sharing procedures among projects, you quickly realize how useful this project really is. It's always a good idea to get "all the details" before plunging in.

May 2001

Part 1: Constructing the Platform
by Ed Sutter

Beginning his series this month, Ed addresses the lack of enthusiasm for monitors. Whether you're a monitor champion or resister, you will benefit from looking at both sides of the equation in this article. Bootroms may be overrunning the monitors, but you can come up with a design that enhances the embedded system and endures for years to come. The reward is improvement in your current implementation, or renewed interest in monitor use.

May 2001

May 2001

May 2001

by George Martin

George likes poking fun at Windows98, comparing it to a challenging computer game, but this month he turns his attention to an analog design project involving a custom car. Transducer interfaces and thermocouples became the topic of discussion for his article, along with noise and filtering. Get set for another analog endeavor as he takes us through the many considerations that come with the territory.

May 2001

by Tom Cantrell

As Tom describes it, L.A. is the epitome of "sun and fun overdone." Still, the heart of the entertainment industry sells a lot of hardware. Sponsoring a group of local college students for the Robotica competition and supplying them with the necessary snacks, Tom goes behind the scenes to follow the trials and tribulations of "Noll." A steady stream of M&Ms can only help foster a kid's imagination.

Got Questions? Want Answers?
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Browse Q&As from other engineers or submit your tough technical questions to the ASK US team and let us help keep your project on track or simplify your design decision.

Test Your EQ presents some basic engineering problems for you to test your engineering quotient.

Problem 1—You are out walking your dog at sunset. You notice that there is a light sensor at the top of the streetlight next to you. This sensor is used to activate the lights along the street. The street lamps are around 100 m (100 yards) apart. You notice that as the lights come on, the nearest light comes on first and the farthest light just a fraction later. If you assume that you can distinguish between two different events about 1/60 second apart, how fast did the sensor signal propagate between the lights?

There is only one problem—yesterday you were walking the dog at the other end of the street when the lights turned on. Then the nearest light again came on first, and the light with the sensor on top turned on last!

Problem 2—A 1-GHz clock signal is distributed to other parts of the circuit as shown below, using a 1-mm copper trace on a low loss substrate (microstrip line No. 1). The trace is split into four 1-mm traces so that the clock signal can be delivered to four subsystems. Is this a good design?

If the amplitude of the clock signal is 5 V into Port 1, what would be the voltage seen at the terminations 2 through 5? Assume that the signal travels along the traces without dispersion or loss, and that all the traces are terminated in matched loads. Disregard any inductance or capacitance at the junction.

The rest of this month's questions

Each month Circuit Cellar's Resource Links provide helpful links and information on a variety of featured topics.

Internet Phones
by Rick Prescott

Wireless Networks
by Brant Schroeder

DVD-R, DVD-RAM, and DVD+RW
by Brant Schroeder

System Controller

RAID System

Precision Film-Foil Capacitors

Stepper Motor Controller

Fiber Optic Sensor

Industrial I/O System

EBX Platform

New Product submissions may be sent to Rick Prescott
4 Park St. Vernon, CT 06066

Read Steve Ciarcia's latest editorial exclusively presented by AVNET.

May 2001

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May 2001

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