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#783: A Bizarre Keyboard Problem with an Unlikely Solution, RotW: SuperDrive Interconnect, Screenshot Tips


Happy Tuesday,

It’s been quite a week for Vermont. While our headquarters in Waitsfield, VT was safe, the water came alarmingly close to the warehouse. The Mad River inundated much of the Valley, leaving propane tanks, hay bales, buildings, fences, vehicles and most anything you can think of strewn about. The cleanup began immediately last Monday with volunteers helping neighbors, friends and complete strangers. By Thursday, many affected homes in my town, Moretown, were completely emptied, their soaking wet contents piled on front lawns and sidewalks. The destruction pales in comparison to that seen in Waterbury and other communities around the state.

Several Small Dog Employees were stranded in Granville, about 20 miles down Route 100. Many communities were left isolated and relied on their neighbors for supplies; National Guard helicopters were seen all week, bringing more food and water as the week went on.

We will rebuild, and most every area is now easily accessible by car. With foliage season approaching, there’s legitimate concern that tourists will not come, thinking the state is closed for business. We are rebuilding, we are open, and a great way to show your support is to come visit!

The Mad River Valley Community Fund is a well-managed group dedicated to helping those in need throughout the Valley. There’s been so much donation of material goods that managing them is becoming problematic, so please consider sending a monetary donation. There’s always the Red Cross, too!

I know next week will bring better news. As always, thanks for reading.


  A Bizarre Keyboard Problem with an Unlikely Solution  

A MacBook Pro came in last week because it refused to render the “d” character when its key was pressed. This is bizarre behavior that I hadn’t seen before; usually when a customer reports this sort of problem, technicians don’t immediately believe it.

We confirmed it was an issue and tried an external keyboard first. The problem persisted, so we knew it wasn’t the keyboard or top case. In MacBook Pros with silver keys on the keyboard, the keyboard and top case are two separate parts. Confirming it wasn’t either part, we booted the computer up from a known-good external source. Your system’s restore disks are the perfect choice here, but we use a fancy NetBoot system that’s much faster and more versatile.

The problem went away when we booted the computer from the external source, confirming that hardware was not to blame. So, after a restart we started narrowing things down. By creating a new account on the computer, you can determine whether the problem is system-wide or isolated to one particular user. Mac OS X is designed for multiple users, but there are core components that all accounts use.

The new account did not show the symptom. Lowercase “d” worked just fine. This meant we needed to look at the user account.

Knowing from experience that this sort of thing usually is a result of fiddling with the Universal Access preference pane, I headed there to look for the case. No luck. Google searches yielded little, and the replacing of various kernel extensions proved ineffective. By chance, I’d clicked on Macintosh HD once, and the name became editable. I decided to try the “d” key again, and the computer spoke “Macintosh HD.”

Off to the Speech preference pane, where I unchecked “Speak selected text when the key is pressed” from the Text to Speech tab. Somehow, lower-case “d” was set to make the computer speak selected text.

  Repair of the Week: SuperDrive Interconnect  

This week’s repair boggled my mind. A 2.33GHz MacBook Pro came in with the simple problem of not booting up from its internal hard drive. I usually start up holding down the Apple and S keys to get into single user mode, and use fsck (file system consistency check) to check and attempt repair to the hard drive’s file system. If it gives an i/o (input/output) error, I can generally assume that the hard drive needs repair. If it attempts repair but fails, I move on to DiskWarrior, which repairs pretty much anything. If that fails, the file system is so far gone that it needs to be erased.

In this case, I went into single user mode and ran fsck, which stated that no problems existed. Since the machine booted past the progress bar and stopped at the same point each time, I thought the issue was software based. I threw in a trusty Leopard disc and went to do an Archive and Install, a nondestructive reinstallation of the operating system, and once the laptop began to boot from the Leopard disk, the screen went dark.

I plugged the MacBook Pro in, thinking the battery went dead, and tried again—but the computer never turned off. I forced a shut down by holding down the power button and then fired it back up, holding down the trackpad button to force the disk to eject before the startup process, then forced a shut down again. I inserted the machine’s original restore disc and tried to boot from that. Same thing: dark screen.

I then plugged the machine into our NetBoot system to see if any external boot volume would keep the screen on. Same thing happened.

Totally baffled, I put the laptop into target disk mode and hooked it up to my own MacBook Pro to capture a backup of the machine. I then reinstalled the operating system from scratch using target disk mode. When it finished, I tried to start it up, and… you guessed it, the screen stayed dark.

At a total loss, I opened the thing up and started removing components, stripping it to a totally minimal configuration of logic board, inverter, display and a few other components. Gradually, I started plugging components in between restarts, using the process of elimination to figure out which hardware component was causing the problem.

When I finally arrived at the SuperDrive, I had my answer. The machine behaved normally until I reconnected the SuperDrive, so I then took a known-good SuperDrive flex connector cable to see if that little cable could cause all this ruckus. Lo and behold, a $10 part needed replacing.

I restored the customer’s data from the backup I’d created and let him know it was ready for pickup. This was truly one of the most bizarre diagnoses to which I’ve ever come.

  Screenshot Tips  

Many of us already know of the ancient keyboard shortcut Command-Shift-3 to capture your screen to a picture file. It’s been around since System 7, and it’s still with us. We’ve made some significant progress over the years. The Command-Shift-3 trick captures a full-resolution image of your screen and places the PNG file on your desktop. From there, you can open and edit the image as you see fit.

It’s rare, though, to need a full screenshot. For these situations, I use Command-Shift-4, which turns the mouse pointer to a crosshairs to allow for precision selection of a portion of your screen. I often find myself writing documentation for company procedures and posting the information to our company wiki (powered by Mac OS X Server), and taking screenshots is a very effective way to visually convey knowledge. I love saving the step of cropping in Preview.

Command-Shift-4 is more powerful than it might seem, though. You can press the key combination and then press the space bar. The mouse pointer changes to a camera, and individual windows and menus are highlighted when you hover over them. Clicking the mouse yields a screen shot of just that window or menu.

The Grab application, found in your Applications folder, allows you to take a timed screenshot by selecting “Timed Screen” from the Capture menu.

These tips can be taken a step further by taking the screenshot and automatically copying it to your clipboard for pasting wherever you’d like. Simple add the Control key to the shortcuts above and you can paste the screenshot directly into any application.

Snow Leopard takes this concept a bit further by allowing you to record video of your actions on screen in QuickTime Player. It records your voice and your screen by default, and it’s my new favorite tool for producing training materials.

  TT SPECIALS | 9/5/11 - 9/12/11  
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