Product Name/Version: PowerMate
OS X ?: Yes.
Company: Griffin Technology
Category: Input Device
Price: US$45
Requirements:
USB Equipped Mac
Mac OS 8.6 or greater/Mac OS X
Date of Review: 3/15/02
Rating: Overall: 4 bounces – Pure Lust

With the original iMac introduced back in 1998, Apple signaled the beginning of a new era for small computer peripherals such as mice, keyboards, joysticks, bar-code readers, etc. Up until then, Mac users had had to put up with the idiosyncrasies of the Apple Desktop Bus (ADB) architecture, including — most notably — the need to restart your machine every time you wanted to plug or unplug anything.

With the iMac, Apple adopted the (Intel-developed) architecture called Universal Serial Bus (USB). USB is truly plug-and-play, in that you may plug and unplug your USB devices at any time without having to turn off your system. Thanks to its greater throughput, it also supports a wider range of devices, including printers, modems, digital cameras, hard drives, scanners, etc. And you can use lots of USB devices at the same time, as long as you have enough available plugs, and as long as those not directly connected to the computer can draw enough power from their USB connection. (If they have their own power supply, then this shouldn’t be a problem.)

Well, we all know what happened with the iMac. It was a tremendous success, the rest of the industry caught up with Apple, and today we have access to what appears to be a full range of USB devices for our Macintosh computers: mice, keyboards, joysticks, bar-code readers, printers, hard drives, digital cameras, card readers, scanners, etc.

However, in most cases, the emphasis in the computer industry has been more on the “plug” part of plug-and-play than on its “play” part. In that respect, Griffin and its little PowerMate device stand out.

Say Hello to PowerMate

The PowerMate is one of these devices that will automatically elicit the same question from all your friends: “What is that for?” It doesn’t look like any other device, and it brings a new, fun approach to the computing experience. It doesn’t look like much, but it can do lots. And it certainly looks cool.

The first thing you notice about the PowerMate, even before plugging it in, is its heaviness. For a round device that’s 2.1 (53.8 mm) inches in diameter and 1.3 inches (33.4 mm) high, it is just as heavy (0.26 lb/0.11 kg) as a mouse that’s at least twice as big. As you start rotating the device, the feel is immediately recognizable: it’s the feel you get from those big volume knobs you find on quality stereo systems.

It also looks just like one of these knobs, with its brushed-metal appearance. And, indeed, one of its default behaviors, once you’ve installed the required software and restarted your machine (because of its low-level functionality, it requires a restart to become fully operational under OS X), is to act as a volume knob.

The last — but not least — aspect of its visual appearance is that its base is made of translucent plastic. And, when the device is plugged in, two LEDs inside the base come on and start emitting a blue glow that shines uniformly through the circular plastic base of the device. (No separate power supply is required. The device draws all the necessary power from its USB connection.)

Once you start playing with the device, you will also notice that the knob can be slightly depressed by pushing on its top. In other words, you can not only rotate the knob in both directions, but also click (and double-click) with it.

But What Does It Do?

This is all very well, but it doesn’t tell us what the device is good for. To find that out, you need to install the appropriate software. The PowerMate that Griffin sent me a couple of weeks ago came with a CD containing a beta version of the PowerMate software, but, since then, the company has released the final 1.0 version of the software, which is available freely on their website.

Installing it under Mac OS X is very easy, but does require a restart, since it relies on what is called a “kernel extension” to provide its low-level system functionality. In my few weeks of using the software, however, I haven’t noticed any incompatibilities.

The PowerMate installer installs three essential components: the extension itself (a file with a “.kext” suffix, inside your System folder), a “PowerMateDriver” application inside the “Application Support” folder in your Library, and a PowerMate preference pane inside the “PreferencePanes” folder in your Library, which adds a pane for the PowerMate to your System Preferences application (in the “Other” section).

The installer also installs an 11-page PDF manual which is your main documentation source for the PowerMate.

The preference pane is the key to interacting with the PowerMate software and configuring it to suit your needs. A quick look at it reveals the power of the PowerMate:

The section called “Action” contains a number of predetermined configurations for the PowerMate. The first one is called “Global Settings” and is used by the PowerMate by default if no app-specific configuration has been created for the application you are currently using. As you can see in the screen shot above, the default behavior is to set the volume level, just like a volume knob would. It’s the fastest way I have found so far to turn the volume down when your computer starts making unwanted noises that you don’t want your coworkers or your sleeping family members to hear. Finding the Volume Up / Volume Down keys on the keyboard or using the Volume menu module in OS X is never quite as fast.

Any Action

The power of the PowerMate is far greater than this, however. The device basically speaks a 6-word language, corresponding to 6 possible user actions:

Each of these actions, in turn, can be assigned to four different computer actions:

The “Adjust Volume Up”, “Adjust Volume Down” and “Mute Sound” actions are self-explanatory. The important one here is the “Type Keystroke”. Selecting this computer action causes a “Keystroke” field to appear below it, in which you may then enter any combination of keys. For example, in the screen shot below, I am entering the cmd-opt-d keystroke:

If I assign this keystroke to the user action “Double Click” in the configuration “Global Settings”, for example, this means that, from now on, double-clicking on the PowerMate will cause Mac OS X to toggle the “Hiding Dock” option on and off. (If you look in the Apple menu, under “Dock”, you will see that cmd-option-d is the keystroke for turning this option on and off.)

More generally, you may thus assign any command for which a key combination exists to one of the PowerMate’s 6 possible user actions.

Application-Specific Configurations

What I did here, however, was add this behavior to the “Global Settings” configuration. But you can also create an application-specific configuration, that will supersede the “Global Settings” configuration whenever the application in question is active.

For example, the default settings of the PowerMate control pane contain a configuration called “Explorer”, which supersedes the default configuration whenever Internet Explorer is the front-most application. In this “Explorer” configuration, turning the PowerMate to the right or to the left will cause the PowerMate to send the “down” or “up” keystroke (i.e. the Down and Up cursor keys) to Explorer, which in turn will make Explorer scroll up or down the currently active web page.

(The ability to use the Up and Down cursor keys to scroll up and down a web page is not documented in the Explorer interface as far as I can tell, but it is definitely there, and the PowerMate configuration takes advantage of it.)

Similarly, you can create a new configuration for, say, Microsoft Word, in which turning the PowerMate knob to the right will cause it to send a “Page Down” keystroke to Word, which in turn will cause Word to jump down one page in your document.

Current Limitations

The possibilities are nearly endless. The only limitations are the following:
The command you want to control needs to have a keystroke. You cannot use the PowerMate to trigger a function that doesn’t have a keystroke. For example, scrolling up and down a Word document with the arrows in the vertical scroll bar doesn’t have a keyboard equivalent — and you cannot use Word’s Customize command to create one, since clicking on the down arrow or the up arrow in the document scroll bar doesn’t have a Word command equivalent (as far as I could tell anyway).
Any app-specific configuration will supersede your Global Settings. In other words, even if you assign no computer action to the “Turn Right” user action in your Word configuration, the “Volume Up” computer action that is assigned to the “Turn Right” action in “Global Settings” will not apply. This is unfortunate, as turning the volume up and down is something that you might want to do even in applications in which you want to use other actions of the PowerMate for other purposes. Maybe this is something that Griffin Technology will remedy in a future version of the software.
The range of keyboard strokes that you can use with the PowerMate is currently limited to the “bare-bones” keyboard layout illustrated above. This keyboard layout doesn’t include the function keys, nor does it include the extra keys of international keyboard layouts or the numeric pad keys. This still gives you quite a range of possible keystrokes and should cover many of the existing keyboard shortcuts of existing applications, but it would be nice to have the added flexibility.

The default PowerMate settings also include configurations for iTunes and iMovie — but you can customize all this. Sometimes finding the keyboard shortcuts for the commands that you’d like to assign to your PowerMate’s actions takes a little research, but that of course depends on the documentation of the corresponding application.

Another problem I found is that, as the Griffin documentation explains, the responsiveness of the PowerMate depends on the way the OS handles the keyboard buffer (which temporarily stores your keystrokes — and the PowerMate’s own keystrokes as well, obviously — before they can be processed). Because of this, you may find that sometimes, when using the PowerMate to send keystrokes to an application, the PowerMate continues to send keystrokes even though you’ve stopped rotating it. This is pretty much unavoidable given the way the PowerMate operates. Fortunately, Griffin has also included a “sensitivity” setting in the PowerMate preference pane that lets you adjust the behavior of the PowerMate and thereby reduce this unwanted side-effect.

Still, with the still significant responsiveness issues in Mac OS X (that have nothing to do with Griffin, of course), I still find that the PowerMate is sometimes inappropriate for actions that would, in theory, benefit from a “turning knob” approach. Let’s hope that future updates to Mac OS X will make this less of a problem and widen the range of commands that the PowerMate can be used for.

The Blue Glow

You might still wonder what this blue glow effect in the base of the PowerMate is for. Well, apart from making your desk look cool in the dark, it does have a function when used in combination with the Volume Up / Volume Down actions, in that the glow increases and decreases according to the volume level. But that’s it.

You can set the PowerMate to “pulse” in true Aqua fashion either while your computer is asleep or all the time, and the frequency of the pulsing is adjustable, but that serves no particular purpose except for increasing the coolness factor.

Conclusion

The really cool thing about the PowerMate is that it invites you to do things differently. After all, knobs are not part of the traditional family of input devices for your computer (the scrolling wheel in some third-party mouse products is the closest cousin I can think of). Yet they have been part of our way of interacting with electronic devices for a very long time, and they do have their advantages.

A knob effectively builds a new bridge between the analog world in which we live as human beings and the digital world of the computer. Even if you take the limitations noted above into consideration, there are still many possible ways of using the PowerMate to enhance your computing experience, and the main limit here is your imagination — and the software you want to use it with.

At a reasonable price of $US45 (with a USB extension cord included), this device is the ultimate cool gadget with a purpose, and it is a great present for your Mac computing friends… or a perfectly good excuse to treat yourself for once!