linux-embedded@waste.org

Frequently Asked Questions

The official repositry for Linux documentation is the Linux Documentation Project which we will refer to simply as LDP. Note that most standard linux installations include a lot of this documentation under the tree /usr/doc, whilst man pages can be seen by using the command 'man whatever' (many distros also include facilities for browsing documentation in HTML). In any case, if you cannot find the HOWTO or manage on your own system, then you will always find the most up to date version at LDP. This site also has links that will help you find non-english versions of the documents.


I'm a Linux newbie, how should I start?

Embedded systems tend to be highly efficient and customised. In order to achieve such goals a good general knowledge of the operating system is essential. Most of what is required for an embedded Linux system will be found in a normal general purpose Linux distribution, so the best way to build up your Linux knowledge is to start using it for your everyday tasks, such as reading this FAQ;-)

Most Linux distributions designed for general purpose use are designed to be as plug-and-play as possible, and hide a lot of administration and configuration from the user. Allthougth this is generaly a good thing, if your eventual aim is to use embedded systems, you may like to consider Slackware which is very much a DIY distribution. For more general information on Linux as opposed to embedding:

  • www.linux.org
  • www.linux.com
  • www.linuxnewbie.com
  • These sites may also help you find Local user groups (LUG's), non english sites, and newsgroups/mailing lists for more genral questions such as "Why will X windows not start"

    Comments/Observations?


    Which Linux distribution is good for embedding?

    Linux distributions generaly fall into one of three broad categories. Standard general purpose distibutions (Red Hat, Suse, Turbo, Cladera etc). Distributions designed for specific purposes such as a secure web server or a Linux based router, and minimalist distributions (several of these fit on a single floppy).

    If there is a distribution specificaly designed for what you are trying to do, then that is obviously a good starting point, otherwise you have the choice of trimming down a big general purpose distribution or building up a minimalistic one. The latter approach is probably the most desirable approach, as you know exactly what is going in. Cutting down a big distro runs the risk of breaking things you did not even know were present.

    Need good sites with catalouges of distros

    Need references to distros of particular interest to embedders

    Comments/Observations?


    How may I make Linux boot faster?

    Make the kernel as small as possible by putting as much as possible into modules which can be inserted later. Supply specific hardware parameters to the kernel so that it does not need to probe values. You may also reduce tasks that init launches at boot, see How do I control what gets started at boot?

    Everybodies favourite tips please!

    Comments/Observations?


    Can I boot Linux from EPROM/FLASH?

    I think we could do with a mini howto here, which we put in LDP and reference

    Comments/Observations?


    What about booting from a CDROM or over a network?

    Is the El torito documentated somewhere?

    Diskless PC (net booting) is in the LDP, link to it

    Comments/Observations?


    How do I control what gets started at boot?

    Cover inittab etc.

    Comments/Observations?


    How can I avoid the login process?

    Good question this, answers? mini-howtos?

    Comments/Observations?


    Can I run program code directly from FLASH?

    Who knows the state of the art?

    Comments/Observations?


    Do solid state disks work with Linux?

    Mention IDE types and other solutions with linux support

    Comments/Observations?


    How can I stop my system being corrupted?

    Intend to talk about mounting RO, the filesystem standard, symlinks, perhaps will do a mini-howto.....other suggestions please!

    Comments/Observations?


    Can I run Linux without VIDEO/KEYBOARD?

    Note serial port support in 2.2.x and LP support upcoming in 2.3.x

    Comments/Observations?


    What about alternative input devices (Touchscreens, matrix keypads etc)?

    Well, whats your favourite input gadget?

    Comments/Observations?


    X Windows eats up memory, what alternatives are there?

    Will talk about minimalist window managers, and smaller versions of X. Need good reliable URL's

    Will also mention SVGA(BGI). Anything else?

    Comments/Observations?


    Can I do embedding with non i386 CPU's?

    Here I need good homepage URL's with short comment on the project status and useability

    Comments/Observations?


    How much memory/disk space will I need?

    I would like to do this by example. If people can tell me that their FOO project which does this, that and everything else requires x/y/z, then I will put up a representative cross section (projects will be presented in an anonymous fashion)

    Comments/Observations?


    Is linux embedded a real time OS?

    Will start this off with a quick explanation of real-time vs real-fast (with nice etc), then if readers are still convinced they want real-time, we put the URL's

    Comments/Observations?


    Are there any small alternatives to standard Linux utility programs?

    Apart from ash, what other suggestions do you have?

    Comments/Observations?


    Linux is GPL'd, does that mean we have to supply all the source code?

    Start with quick 'not necessarily for your code' bit, and list the normal solutions for the rest of the GPL stuff.

    Then I would like links to places with long winded explanations, other than the FSF, does anybody know of other good URL's for these topics?

    Comments/Observations?


    Can Linux run on embedded hardware such as credit-card PC's

    Nowdays PC's come in a whole smorgasboard of form factors. Compact PCI, credit card sized modules, PC 104, PC on a DIMM......

    Linux will run on just about all these products, with many manufacturers actively supporting Linux. Make a shortlist of the products that most interest you (or the type of product), and then post to the list in case somebody has tales of woe, or particular recomendations.

    Comments/Observations?


    How can I access (interface to) my proprietry hardware?

    Start by refrencing the IO-ports HOWTO, and then go on to explain about the joys and simplicities of kernel modules. Will cite Alessandro Rubini's book, what about URL's?

    Comments/Observations?


    How can I use industrial interfaces such as CAN, PROFIBUS and IEEE488?

    I know about the stuff for CAN and 488 on the Linux LAB project, anybody have any other pointers/info?

    Comments/Observations?


    What OSS alternatives are there to embedded Linux?

    Need official home URL's for stuff such as PicoBSD and eCos....whatever

    Will also cite ELKS

    Comments/Observations?