How To Add a USB Keyboard to an Android Phone

Are those puny hardware buttons or the quirky on-screen QWERTY keyboards not quite cutting it for you in Android? As it turns out, Google’s (s goog) mobile platform appears to support USB keyboards natively on some stock builds. Of course, you can’t simply attach a big, honking external keyboard to your phone and expect it to work. You have to enable USB-OTG, or USB On The Go host mode, and have the proper USB cable, says MAKE. Luckily, Chris Paget’s blog shares the steps to make this happen. The whole process reminds me of a similar project that modders got into back in 2008 with the Nokia N810 Internet Tablet. I was scared of the soldering then, and sadly, I’m no closer to having a comfort level.

Chris makes the magic happen on his Droid (s mot) with three parts: a car charging cable, a micro USB cable and a USB extender cable — all pretty basic parts. The charging cable is only needed for the end piece — it becomes a micro USB dongle that tells Android there’s a USB device to install, which enables USB-OTG mode for the current session. The other two cables are needed for their ends and get spliced together: one end plugs into the handset and the other accepts a male USB wire from a keyboard. Maybe I could handle the wee bit of soldering on this one since it’s only needed to short out one resistor on the micro USB dongle. I think I’ll just search for a pre-made cable to do the trick.

Armed with the proper pieces, it’s just a matter of booting up Android with the dongle in the phone. Once the handset sees the dongle and continues to boot, you simply remove the dongle and plug in a USB keyboard with the spliced cable. Android sees the keyboard, and as Chris says, “It Just Works.” A similar process was replicated and tested successfully on an HTC Hero as well, so odds are decent that many other Android phones can use USB-OTG to host a keyboard. No additional drivers were needed for either the Droid or the Hero, so keyboard support has to be built within Android itself. Of course, that means it could go away in any future Android updates, but for now, you can enjoy a full-sized keyboard on your pint-sized phone.

Image courtesy of Andrew de Quincey

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