Though embedded Linux systems differ greatly, the method outlined in this book should readily apply to building any sort of embedded Linux system. It follows from this that it is possible to lay out a set of rules for specifying the particularities of each embedded Linux system. The worksheet presented in this appendix does just that. Once completed, any developer can use a worksheet in conjunction with the explanations in this book to recreate an embedded Linux system without any assistance from the original designers. During development, the worksheet can be used by members of the development team to obtain detailed information regarding each component of the system.
The worksheet contains one section for detailing each aspect of an embedded Linux system. Each section contains a set of attributes pertaining to the aspect of the embedded Linux system it describes. The sections are:
Storage device organization
Bootloader configuration and use
Custom project software
Most sections include a "Main contact" field. This field should be used to specify the name of the person responsible for this particular aspect of the embedded system during development. The person in charge of a certain aspect of the system is expected to be aware of the various caveats and keep up to date with the recent developments of the relevant open source and free software packages. The person responsible for the kernel, for example, should ideally be subscribed to the Linux kernel mailing list and the kernel development list for the architecture the system is based on.
Though the worksheet attempts to be as exhaustive as possible, you may need to modify it and extend it for your project's purposes. The number of entries for listing some system components, such as the "Peripherals" list in the "Hardware summary" section for example, may be insufficient to describe your system. Feel free to add more pages to leave more space for detailing your system's characteristics.
A copy of the blank worksheet is available for download in PDF and OpenOffice format from the book's web site at http://www.embeddedtux.org/. Alternatively, you can photocopy the worksheet included in this appendix. Avoid writing directly in this book, however, as you may want to make changes to your worksheet and use the book across different projects.
The rest of this chapter describes each section of the worksheet in detail. Though the meaning of most fields should be apparent, some fields may require some explanation. Whenever appropriate, references the relevant chapters are provided.