The same is true for rebuilding the kernel. You will need to do this if you add peripheral support or you want the applications to be part of the system flash-memory image. Likewise, you need to rebuild if you want to add or delete features to the Linux runtime. The base system features support for a number of network applications, including SSH, but if you want to drop on something like the Apache web server then be prepared to do some work. In general, you only need to configure your PC to rebuild properly once. From then on it is a matter of running a batch file or make file.
I also had my hands on a RoboStix (see Fig. 3). This is an interesting combination. It provides connections for power and it has its own 8-bit AVR microcontroller. You will need a JTAG emulator and AVR tools if you plan on reprogramming the AVR, but it is very easy to do once you know what you are dealing with and have some AVR expertise. The complete hardware documentation for this and the other Gumstix boards is available online, so the only mystery is how long it will take for you to find what you want.
The more likely route is to use the system as is with the XScale processor telling the AVR how to manage the PWM (pulse width modulation) and other interfaces on the board. Sample code is available online. Again, once you get the AVR management basics down you can concentrate on your application. You do not need to know anything about the AVR to control its interfaces.
Gumming Up The Works
Gumstix modules can be used in production products, although their connectors and hole positions will require custom mounting, host boards, or cases. Still, the results can be extremely compact and the low power requirements lend themselves to mobile applications.
Roboticists will be especially pleased with the selection of products. The Bluetooth support makes the systems ideal for mobile robots. There are a number of robot projects using the modules. Links for these can be found on Gumstix Wiki and forums.
Gumstix is improving the software support, but at this point the initial setup is best handled by someone with some minimal Linux expertise. Otherwise, be prepared for a learning curve of about a week if you’re primarily a hardware jock. Getting familiar with the Gumstix hardware and software is worth the effort if you don’t need a product or project done in a couple weeks.
Bottom line: highly recommended for the technical at heart.
Read next review: Xscale Module Kit Delivers PCI And VGA Support