Embedded Linux system learning embedded Linux system knowledge outline carding

To learn embedded knowledge, embedded Linux, you need to learn the embedded Linux system infrastructure knowledge, according to the plan to learn, now let the small taping everyone familiar with the embedded Linux system basic concepts. Things always have a core, complex things can always be modular, hierarchical, embedded Linux is also the case. Learning embedded Linux difficulties, mainly because of the knowledge and concept of too much, so learning embedded Linux needs to find the core, need to be modular, need to be hierarchical division.

Embedded Linux systems are modular and can be divided into bootloader (boot program), Kernel (kernel), FS (file system), Shell (command line interface), Gui (graphics library) and embeded SQL (embedded database) and so on. The above is the embedded Linux System 7 important modules, through which you can develop a variety of apps (applications). such as Internet use Web browser, play songs audio player, play movie video player, various games (such as repeatedly see) and so on.

Embedded Linux Systems--boot programs, bootloader and PC BIOS programs are some types, the biggest is to install the system, just like the PC just bought if not installed operating system, you need to install the operating system, PC installation Windows operating system usually starts from the CD-ROM, Press the FN key to enter the installation mode to read the disc and start the installation process. Embedded Linux is similar to this, bootoader the boot process by pressing any key (U-boot) into the installation mode, except that the installation is not from the optical drive to read the system, but from the serial port (UART) or the network port reading system. There is also a different PC installation file system included in the system, embedded Linux system operating system and file system are separate needs to be installed separately.

Embedded Linux system-the kernel, kernel, is the core of the Linux system, kernel contains drivers, network protocols, memory management, file systems, process management modules, these concepts are more abstract, in the Windows operating system to do program development will encounter similar module division, If only the Windows operating system's application is rarely required to have these concepts, but you use these things. If the external expansion of the device needs to install additional drivers, you use the driver of this thing, you use the file system when you open Office, Internet Protocol, while opening the chin listening and calculator You use the process management. The original embedded Linux system concept has long existed in the Windows operating system, like meeting a familiar person, want to ask "we seem to have met there."

Embedded Linux System--file system, FS, is an important part of Linux system, the file system mainly implements the operation of folders and files (such as Create, delete, open, close, read and write, etc.), which is similar to the file system of Windows operating system. Embedded Linux System file system module usually needs kernel to provide support, and contains shell command package, that is, the embedded Linux file system not only provides support for file operation, but also provides support for Shell package, you may have doubts about what is the shell, please look down.

Embedded Linux system-the command line, the shell is an important part of the operating system, of course, including embedded Linux systems. Under Windows operating system, open "start" point into "run" input "cmd" press "enter" key, you entered a "Soil" window interface, this interface is a Shell, enter "ipconfig" You can see the IP information of this PC. Embedded Linux system also has a similar shell, but not mapped to this machine (such as ARM hardware board), but mapped to the PC serial terminal (here more concepts, it is recommended to remember "map" "Arm board", "PC", "Serial terminal" the key words), That is, through the PC serial terminal can operate the embedded Linux shell, such as the input "ifconfig" can view the ARM hardware Board IP information, this and the above "ipconfig" function the same.

Embedded Linux system-graphics library, that is, the GUI is used to do graphics surface support library. such as the "desktop" under the Windows System, the icon on the "desktop" is implemented using the graphics library. You use the mobile phone display background, display the phone number, text messages are also based on the graphics library to achieve. Embedded Linux system is not necessarily used in the graphics library, so the graphics library is one of the embedded Linux system can be cut, the current popular graphics library has QT/MINIGUI/GTK+2/MFC, in addition to MFC can be used in embedded Linux system.

Embedded Linux system-embedded database, or embeded SQL, is another important cutting module of embedded Linux system, that is to say some embedded Linux system products may be used, some may not be used, the most popular embedded database is Sqlite. So what does an embedded database do, and if you know the database, you can think of the embedded database as a small, lightweight database. If you do not understand, please imagine a class of transcripts (table), each student's performance to review and ranking, then the report card is equivalent to the database, the review process is equivalent to the database search (retrieval), the results of the view as if the search (retrieval) results, Ranking is the equivalent of creating an index on a database member by rank. The simple point-"database is the operation of tables and tables."

After reading how it feels, the basic concept of embedded Linux system is not some understanding, want a deeper understanding of embedded Linux, then to create a college embedded training, with the embedded big God in the embedded training to learn, together to exchange, to use technology to change life!

Embedded Linux system learning embedded Linux system knowledge outline carding