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Linux: Pocket Linux Guide - Linux Pocket Guide. LFS - News. The Swiss Army Knife of Embedded Linux. BusyBox combines tiny versions of many common UNIX utilities into a single small executable. It provides minimalist replacements for most of the utilities you usually find in GNU coreutils, util-linux, etc. The utilities in BusyBox generally have fewer options than their full-featured GNU cousins; however, the options that are included provide the expected functionality and behave very much like their GNU counterparts. BusyBox has been written with size-optimization and limited resources in mind. It is also extremely modular so you can easily include or exclude commands (or features) at compile time. This makes it easy to customize your embedded systems. To create a working system, just add /dev, /etc, and a Linux kernel.

BusyBox is extremely configurable. After the compile has finished, you should use 'make install' to install BusyBox. BusyBox is a multi-call binary. You can also invoke BusyBox by issuing a command as an argument on the command line. Acpid Options: addgroup adduser ar arp cp. GNU/Linux comme système d'exploitation embarqué. Sous-sections De plus en plus d'objets quotidiens embarquent avec eux de l'intelligence.

Un ordinateur embarqué se définit généralement par le fait qu'il n'est pas visible en tant que tel, mais est intégré dans un équipement doté d'une autre fonction ; on dit aussi que le système est enfoui, ce qui traduit plus fidèlement le terme anglais embedded. Un inventaire à la Prévert serait nécessaire pour citer les systèmes informatiques embarqués que nous utilisons quotidiennement: gestion de l'ascenseur, auto radio, calculateur d'``air bag'', distributeur de boissons, routeur Internet ou téléphonique, téléphone mobile, distributeur de billets, une console de jeux, une carte graphique (bientôt un raton laveur car le chien électronique existe déjà !!))... Nous voyons bien que les contraintes imposées à tous ces systèmes ne sont pas les mêmes: qu'y a t'il de commun entre un satellite et une imprimante, à part le fait de contenir des processeurs ?

Architectures matérielles Plates-formes logicielles. :: Thinstation FAQ :: Embedded. Booting Linux from Compact Flash - Gumph. Use a silent Compact Flash card to boot your pc, for either reduced noise, or a long life solution, with no moving parts. Ideal for firewalls, routers, or small servers. Compact Flash is not really designed to replace your harddrive, but to just provide space you can load a filesystem image into ram from. It is not suited to the continual read/writes of normal hardrive use, so a ramdisk is loaded from the CF card, into memory, and linux run from there. This means that linux is running fast, but you need enough memory for both the filesystem image, and the operating system to use. In fact you need enough memory for over two filesystem images in order to boot, as Linux copies the filesystem image in memory when it boots.

In the example setup I used a 97Mb filesystem image (which compressed to 35Mb) , 256 MB Ram and a 256 MB CF card. A 64MB CF card would have sufficed. So whats involved in getting linux onto the compact flash I hear you ask, Installing Linux >> Make a filesystem Image. Applications : How to use a Ramdisk for Linux. How to use a Ramdisk for Linux Abstract: This article shows how to use RAM as a virtual harddisk. Introduction to RamDisk This is a brief article about how to setup a RamDisk on a RedHat 6.0 system. What is a RamDisk?

Here are some more resources to help you. How to use RamDisk Well, it is very easy to use a ramdisk. . # create a mount point: mkdir /tmp/ramdisk0 # create a filesystem: mke2fs /dev/ram0 # mount the ramdisk: mount /dev/ram0 /tmp/ramdisk0 Those three commands will make a directory for the ramdisk , format the ramdisk (create a filesystem), and mount the ramdisk to the directory "/tmp/ramdisk0". The default size of the ramdisk is 4Mb=4096 blocks. Mke2fs 1.14, 9-Jan-1999 for EXT2 FS 0.5b, 95/08/09 Linux ext2 filesystem format Filesystem label= 1024 inodes, 4096 blocks 204 blocks (4.98%) reserved for the super user First data block=1 Block size=1024 (log=0) Fragment size=1024 (log=0) 1 block group 8192 blocks per group, 8192 fragments per group 1024 inodes per group Comments. The Linux Bootdisk HOWTO. User-space device drivers. [Posted January 20, 2004 by corbet] Peter Chubb works with the Gelato project, which works toward better Linux performance on the IA-64 architecture.

Among other things, Peter is responsible for the 64-bit sector support which went into the 2.5 kernel. At Linux.Conf.Au, Peter discussed device drivers. He pointed out that drivers, while making up roughly 50% of the code in the kernel, are responsible for 85% of all kernel bugs. Drivers tend to be written by people who would not normally be considered kernel hackers: hardware engineers, for example. These people tend to have a hard time dealing with the special nature of kernel programming, where interfaces are fluid, bugs are lethal, and many normal development tools are not available. Driver authors - and their users - might have a much easier time if drivers could be written to run in user space. Peter and company have set out to make user-space drivers possible. Int usr_pci_open(int bus, int slot, int function); UserLevelDrivers - IA64wiki. Most drivers are tightly bound into the kernel, either linked to it, or loaded as modules at runtime.

Some drivers (notably XFree86's X server) run in user space, and map device registers, video memory, etc., into their own address spaces. By moving device drivers out of privileged kernel space into user space, their bugs can be contained. As of linux 2.6.0-test5, user processes can: mmap() /dev/mem to get at MMIO registers (not safe on all architectures) Use inb() etc., for ports below 65536 Read and write the PCI configuration space There is also a patch by Albert Calahan that allows mapping bits of PCI space, at --- this is a better way to go than mapping /dev/mem directly. In 2.6, it should be possible to use ioctl on /proc/bus/pci/XXX to get at the appropriate parts of I/O space. Threads The new Posix Threads Library NPTL provides vary fast threading and mutexes.

Fast System Calls Interrupts We added two new system calls: The third argument looks like this: Device Drivers. The HyperNews Linux KHG Discussion Pages If you choose to write a device driver, you must take everything written here as a guide, and no more. I cannot guarantee that this chapter will be free of errors, and I cannot guarantee that you will not damage your computer, even if you follow these instructions exactly. It is highly unlikely that you will damage it, but I cannot guarantee against it. There is only one ``infallible'' direction I can give you: Back up! What is a Device Driver? What is this ``device driver'' stuff anyway? User-space device drivers It's not always necessary to write a ``real'' device driver.

Device Driver Basics Assuming that you need to write a ``real'' device driver, there are some things that you need to know regardless of what type of driver you are writing. Character Device Drivers This section includes details specific to character device drivers, and assumes that you know everything in the previous section. TTY drivers This section hasn't been written yet. LinuxGraphic.org : 3D, Blender, POVRay, OpenGL, 2D, Gimp, Skencil, Sodipodi.

A 3D animation of Linux source code development. The Labs AfterStep. Last update 2001/07/23 The Labs - Design & Functionality For The Net AfterStep, A alike X11-Window Manager AfterStep is an X11 Window-Manager of one of the best designed. Nowadays Enlightenment and WindowMaker provide more up-to-date design approach, but still lack of a good Pager. AfterStep comes with it where you can create multiple "virtual-screens" which each can be 2x2 to physical size each. There are now two AfterStep developed (fortunatly or unfortunately): AfterStepClassic 1.x (1.0 with bug fixes), check for most recent code. FEATURE:AfterStep is a NeXT-Desktop alike X11-window manager, it has some advanced design and look-and-feel better as many other X11 window managers (twm, fvwm).

So, if you are interested you have a good-looking window-manager, you may consider to use AfterStep for sometime. In the sample.steprc in the distribution are popup menus defined, here two examples: For detailes how to change or add menus, look at sample.steprc. [Léa] Léa, site d'aide Linux francophone. Da Linux French Page.