Change zoom to scroll on a Microsoft Natural keyboard

Question

I've got a new Microsoft Natural Ergonomic Keyboard 4000 (what a great product name), and I'm using it under OS X Snow Leopard. The zoom nub in the middle is pretty much useless to me, so I'd rather make it scroll. How do I do that?

The same question, but for Windows: Change Zoom Action to scroll in a MS Natural Keyboard 4000

Answer 1

Unlike Windows, the Mac Microsoft keyboard driver doesn't use a commands.xml file for the configuration. Instead, it uses a binary file, which makes it tough to modify. The configuration file is stored at:

/Users/YOUR_NAME/Library/Preferences/com.microsoft.keyboard.pref

With a bit of reverse-engineering, it's possible to determine enough of the binary file format to modify it and remap the zoom slider. I have created a modified pref file that remaps the zoom slider to UP and DOWN arrow key presses. Unfortunately when I tried remapping it to the SCROLL function, it didn't autorepeat, so UP/DOWN seemed like a better option.

There is a trick to installing a new pref file and getting the keyboard driver to reload it:

1. Make sure System Preferences is closed
2. Download the modified pref file (above)
3. Navigate to /Users/YOUR_NAME/Library/Preferences/
4. Back up the com.microsoft.keyboard.pref file (e.g. rename it to com.microsoft.keyboard.pref.old)
5. Move the modified pref file into that folder
6. Open System Preferences, and open the Microsoft Keyboard preference panel (this causes the pref file to be reloaded)
7. The zoom slider should now send UP/DOWN keypresses (Note: changing any of the zoom preferences within the System Preferences window will overwrite the remapping - reverting it back to zoom!)

If you're interested in remapping the zoom slider to something else, I've described the reverse engineering process in more detail on my blog - it involves taking hex dumps of the binary pref file and comparing those hex dumps when you change particular items from the control panel.