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A Different Kind of USB Scope GUI

Summary: We need a new way to interact with those inexpensive USB scopes and logic analyzers.

I've evaluated many small USB scopes and logic analyzers over the years (most recently the Logic16: http://www.embedded.com/electronics-blogs/break-points/4420012/Logic16). These devices are generally pocket sized, very inexpensive, offer a lot of functionality for the money, and use your PC for the UI. Most have beautiful screens.

But I'm not a fan of screen-based controls. Obviously, one saves a ton of money by leveraging the PC's resources, but it is frustrating to have to grab a mouse and then carefully move a virtual control to change a channel's vertical resolution or fiddle with the triggering or time base. You just can't beat a stand-alone instrument for ease of use when holding two probes in your hands, a third in your mouth and another between two toes. Somehow one manages to just barely nudge that vertical control with the knuckles or nose. The PC interface is far less amenable in those circumstances.

Owning an iPhone and iPad I find myself occasionally trying the two-finger squeeze on my 4 year old MacBook when using one of these USB instruments. One quickly gets used to new interfaces and it's a bit jarring when the Mac doesn't respond to touch commands.

While at Best Buy the other day, trying to avoid the 18 year old salespeople, I looked at a variety of PCs with touch screens. The screens worked surprisingly well. Clearly touch and gesture (see my comments about Microchip's GestIC (http://www.ganssle.com/tem/tem231.html) will dominate over the next few years.

When will the USB instrument folks provide a touch-screen interface? I envision one with large controls that can be activated by the crudest of motions for those times all four limbs are holding probes. A little nose action could move a vertical gain slider up or down; a brush of the elbow changes the time/division.

What about voice activation? That might be even better than the UI provided by a bench scope. "Scope: trigger at 2.4 volts." "Scope: 20 msec/division." It might be hard to choke out an intelligible command with a X10 in your mouth, but perhaps a grunt filter could translate. Just a few days ago my assistant had to stand over my bench and punch the "single sweep" button when I asked because my hands were balancing three probes; it sure would have been nice to just command "Scope: single sweep."

The instruments would need addresses of course, so in a lab full of engineers Joe's commands won't drive Bob's scope.

Shortly after saving this article to disk, an email arrived from the NSA. They seem to know my Agilent's IP address, and wrote that if I say "NSA: single sweep" near the PC's mike they'll take care of it for me.

Published May 24, 2013