Portable Devices on the Gumstix Platform
The Gumstix platform works very well for constructing portable device prototypes. Since the XScale chip on the Gumstix is largely identical to those found on PDAs two or three years ago, the Gumstix is easily usable for portable electronics. However, most of the resources and sample projects on the web that feature Gumstix boards are for headless embedded devices and robots.
We recently built a two-display e-book reader using the Gumstix platform. The hard part was finding all the information that was scattered around the internet. Therefore, we hope a page detailing the steps we used to build a Gumstix-based device with Bluetooth connectivity and an LCD display will be helpful to others trying something similar. Since the prototype we built is part of an ongoing research project, we're constantly adding functionality, discovering problems, and finding workarounds.
In this guide, we describe an open design for a e-book reader, which can easily be extended to other portable devices like PDAs or game systems. The major sections of the guide (which happen to correspond the major components of our reader) consist of:
- Software setup - Getting Windows CE 5.0 running
- Interface board - Breaking out signal lines to interfacing with the Gumstix Mainboard
- Sensors - Attaching additional sensors and switches
- Hooking up an LCD - Connections, backlight, and writing drivers
- Casing - Constructing a box to hold everything
Other resources
We got our information from a variety of other webpages. These will probably be helpful if something isn't listed here.
- The guys at E-Ink use a Gumstix board to power their e-paper displays, and their Thinspace package has excellent examples about how to do low-level embedded programming (i.e. controlling GPIOs) on Linux.
- RoombaNet hooks up a Gumstix to a Roomba. We decided building our own breakout was not out of the question after seeing this page. The page also has some good information about interfacing with power sources other than the standard 4V power adapter from Gumstix.