features of µC/FS are: 

·  MS-DOS/MS-Windows compatible FAT12 and FAT16 support. 

·  Multiple device driver support. You can use different device drivers with µC/FS, which allows           you to access different types of hardware with the file system at the same time. 【在該文件系統(tǒng)中可同時(shí)支持多個(gè)設(shè)備驅(qū)動(dòng)】

·  Multiple media support. A device driver does allow you to access different medias at the same            time. 

·  OS support. µC/FS can easily be integrated into any OS. In that way you can make file operations        in a multithreaded environment. 

·  ANSI C stdio.h like API for user applications. An application using standard C I/O library can             easily be ported to use µC/FS. 

·  Very simple device driver structure. µC/FS device drivers need only very basic functions for                 reading and writing blocks. Therefore it is very simple to support your custom hardware. 

·  Generic device driver for SmartMedia cards, which can easily be used with any kind of card                  reader hardware. 

·  Generic device driver for MultitMedia & SD cards using SPI mode, which can be easily integrated.

上面的圖是FATFS,但與UC/FS的是一樣的

   1：API層【類似于linux的VFS層】

      The API layer is the interface between µC/FS and the user application. It does contain a library of ANSI C oriented file functions, such as  FS_FOpen, FS_FWrite etc. The API layer does transfer these calls to the file system layer. Currently there is only a FAT file system layer available for µC/FS, but the API layer can deal with different file system layers at the same time. So it is possible to use FAT and any other file system at the same time with µC/FS.  

    API層是µC/FS 提供給用戶使用的接口層（fs_api.h），API層將各種調(diào)用傳輸?shù)?/span>file system layer（文件系統(tǒng)層），目前對(duì)µC/FS（文件管理實(shí)現(xiàn)機(jī)制）來(lái)說(shuō) 只有一個(gè) FAT文件系統(tǒng)層被使用，API層可以處理不同的文件系統(tǒng)層，因此µC/FS可同時(shí)支持多種文件系統(tǒng)（API層類似于linux中的虛擬文件系統(tǒng)VFS，他的功能是提供給童用戶標(biāo)準(zhǔn)的系統(tǒng)調(diào)用接口，VFS層下面才是具體實(shí)際的文件系統(tǒng)層，有FAT、EXT2等等，這個(gè)根據(jù)硬件的情況（格式化時(shí)使用什么文件系統(tǒng)）來(lái)調(diào)用具體的文件系統(tǒng)）。

   2：File System Layer 文件系統(tǒng)層【這層與linux是一樣的，是具體的管理文件所用的文件系統(tǒng)】

   The file system layer translates file operations to logical block operations. After such a translation, the file system calls the logical block layer and specifies the corresponding device driver for a device.

   文件系統(tǒng)層將文件操作轉(zhuǎn)換為邏輯塊操作，之后，具體的文件系統(tǒng)調(diào)用邏輯塊層函數(shù)并指定設(shè)備相應(yīng)的驅(qū)動(dòng)；【linux中，文件系統(tǒng)將各種系統(tǒng)調(diào)用轉(zhuǎn)換為各種IO請(qǐng)求（系統(tǒng)請(qǐng)求即是對(duì)底層相應(yīng)的扇區(qū)、柱面、等操作），IO請(qǐng)求被放到對(duì)應(yīng)設(shè)備的IO請(qǐng)求隊(duì)列中去，再由一個(gè)系統(tǒng)內(nèi)核線程一直讀取請(qǐng)求隊(duì)列中的請(qǐng)求，沒有請(qǐng)求時(shí)就睡眠，拿到請(qǐng)求就通過設(shè)備驅(qū)動(dòng)實(shí)現(xiàn)具體的操作】

    uC_FS\FSL\fat\ 下面就是FAT文件系統(tǒng)的各個(gè)文件。

   3：Logical Block Layer 邏輯塊層

   the main purpose of the logical block layer is to synchronize accesses to a device driver and to have an easy interface for the file system layer.  The logical block layer does call a device driver to make a block operation. 

   邏輯塊層的主要目的是同步訪問設(shè)備驅(qū)動(dòng)與文件系統(tǒng)的簡(jiǎn)易接口，邏輯塊層調(diào)用設(shè)備驅(qū)動(dòng)來(lái)實(shí)現(xiàn)設(shè)備的塊操作。

 

   1:調(diào)用FS_Init()初始化文件系統(tǒng)，在使用uC/FS的任何功能函數(shù)之前須要首先調(diào)用該函數(shù)進(jìn)行初始        化；

           2：調(diào)用應(yīng)用程序中的函數(shù)_write_file()【非uc/fs的函數(shù)】

     讀： FS_FOpen()->FS_FRead()->FS_FClose()

   1：Create a simple project without µC/FS 

      We recommend, that you create a small “hello world” program for your system. That project should already use your OS and there should be a way to display text on a screen or serial port. 

   2: Add your µC/FS configuration

      In order to configure  µC/FS for your system, you should create a new sub-directory in µC/FS’s config directory and copy the files  fs_conf.h  and fs_port.h from one of the other sub-directories to your directory. For the following chapters, we assume that you have created a directory FS\CONFIG\myconfig. Usually, the only file  you have to modify is fs_conf.h. For an easy startup, we recommend, that you disable all drivers except the RAM disk driver. Please check out the chapter “Configuration of µC/FS” for detailed information about the configuration.  

     Add all source files in the following directories:

     and their sub-directories to your project.  

        FS\API 

        FS\CONFIG\myconfig 

        FS\LBL 

        FS\OS

   5: Add generic sample code

       For a quick and easy test of your µC/FS integration, you should use the code 

       found in FS\sample\main.c.  

 

     This is the main configuration file for the file system. You define which drivers you want to use and, the configurations for these drivers.

      【用戶手冊(cè)中列出了一個(gè)配置樣本】，包括下面的各個(gè)配置項(xiàng)目

    1：OS support 

      You can specify whether you are using uC/OS-II, embOS, Windows or no OS support at all.  Please set  FS_OS_UCOS_II,  FS_OS_EMBOS, FS_OS_WINDOWS to 1, respectively. For no OS support at all, set all of them to 0. If you need support for an additional OS, you will have to provide functions described in the chapter “OS integration”. 

    2：Time/Date support 

      If you want to be able to add date and times to your files, you will need to set 

FS_OS_TIME_SUPPORT  to 1. 

    3：File System Layer Support

      µC/FS can support different file system at the same time. You can enable them by setting FS_USE_XXX_FSL, where XXX is the name of the file system layer. The current version of µC/FS only supports the FAT file system, so you will need to set FS_USE_FAT_FSL to 1.

I      RAM Disk:       to  1

       Windows Driver:    FS_USE_WINDRIVE_DRIVER to 1