Daily Archives: September 15, 2011

USB Host mode on Touchpad

So, this is pretty spiffy.  USB host mode works actually on the Touchpad.  This means you can in theory, add stuff like memory sticks, 3G dongles, hard drives, etc to your HP Touchpad.  Of course, there’s a catch. :)   (always a catch).  The Touchpad does not supply any power from it’s USB port.  Even tho it’s auto-sensing that it can switch between host and device, it never ends power there.  So, that presents a slight challenge, but not too hard.

With a few simple cables and a power source I was able to get it to read and mount a little 2Gb USB thumb drive.  You just need the proper cables and power.  The cables are all found on eBay fairly easily from Hong Kong for a few bucks.

First, here’s a pic of the rigging. :)

A little messy but not too bad. :)    On screen is an XTerm via Xecutah. As far as I know WebOS  has no real way to know about this stuff on it’s own.  You’ll need to get to a local console to actually activate/use anything you plug in.

Here’s a screenshot with the details.  The USB stick showed up as /dev/sda.  I mounted to a temp mountpoint under root’s homedir.

Here’s a closeup of the cables used.  I used my HP Touchpad’s AC power adapter to provide power with the USB Y-Cable.

And here’s a closeup of the cable going to the Touchpad itself.  Just plug this into the touchpad, the Y “power injector” cable into this one, then your device into the female end of the Y cable.

And there ya have it!    Now to figure out how to get a 3G WWAN dongle to work. :)

Also, a thought for more portable power.  I’ve got an Energizer Energi-to-Go battery pack.  I may see if I can rig that up somehow to a cable to provide power to the devices.  that’ll give me something smallish to carry in my bag with the Touchpad.

Here’s a few links to the stuff used.

The Micro-USB cable to Female USB A adapter: http://www.ebay.com/itm/110726781644
The USB Y-Adapter (power injection) : http://www.ebay.com/itm/290578498858