fatfs可配置项很多，相关的配置均在ffconfig.h文件中
/*---------------------------------------------------------------------------// Function Configurations 功能配置/---------------------------------------------------------------------------*/#define _FS_READONLY 0 //是否只读，只读模式下所有和写操作相关的api均被移除/* This option switches read-only configuration. (0:Read/Write or 1:Read-only)/ Read-only configuration removes writing API functions, f_write(), f_sync(),/ f_unlink(), f_mkdir(), f_chmod(), f_rename(), f_truncate(), f_getfree()/ and optional writing functions as well. */#define _FS_MINIMIZE 0 //通过移除基本API来裁剪代码，使代码最小/* This option defines minimization level to remove some basic API functions.// 0: All basic functions are enabled. 所有基本功能有效/ 1: f_stat(), f_getfree(), f_unlink(), f_mkdir(), f_chmod(), f_utime(),/ f_truncate() and f_rename() function are removed./ 2: f_opendir(), f_readdir() and f_closedir() are removed in addition to 1.- / 在1的基础上移除目录相关函数
/ 3: f_lseek() function is removed in addition to 2. 在2的基础上移除f_lseek函数 */#define _USE_STRFUNC 0 // 是否使能字符串函数/* This option switches string functions, f_gets(), f_putc(), f_puts() and/ f_printf().// 0: Disable string functions./ 1: Enable without LF-CRLF conversion. 使能字符串函数，但不包括LF-CRLF（不同系统下的换行）转换/ 2: Enable with LF-CRLF conversion. */#define _USE_FIND 0 // 配置文件夹查找过滤及相关函数/* This option switches filtered directory read feature and related functions,/ f_findfirst() and f_findnext(). (0:Disable or 1:Enable) */- #define _USE_MKFS 0
/* This option switches f_mkfs() function. (0:Disable or 1:Enable) */#define _USE_FASTSEEK 0 // 快速查找/* This option switches fast seek feature. (0:Disable or 1:Enable) */#define _USE_LABEL 0 // 磁盘卷标/* This option switches volume label functions, f_getlabel() and f_setlabel()./ (0:Disable or 1:Enable) */#define _USE_FORWARD 0 // 数据流转法/* This option switches f_forward() function. (0:Disable or 1:Enable)/ To enable it, also _FS_TINY need to be set to 1. *//*---------------------------------------------------------------------------// Locale and Namespace Configurations // 地区和命名空间配置/---------------------------------------------------------------------------*/#define _CODE_PAGE 932 // 配置目标系统OEM code/* This option specifies the OEM code page to be used on the target system./ Incorrect setting of the code page can cause a file open failure./ 错误的配置会导致文件打开失败/ 1 - ASCII (No extended character. Non-LFN cfg. only)/ 437 - U.S./ 720 - Arabic/ 737 - Greek/ 771 - KBL/ 775 - Baltic/ 850 - Latin 1/ 852 - Latin 2/ 855 - Cyrillic/ 857 - Turkish/ 860 - Portuguese/ 861 - Icelandic/ 862 - Hebrew/ 863 - Canadian French/ 864 - Arabic/ 865 - Nordic/ 866 - Russian/ 869 - Greek 2/ 932 - Japanese (DBCS)/ 936 - Simplified Chinese (DBCS)/ 949 - Korean (DBCS)/ 950 - Traditional Chinese (DBCS)*/#define _USE_LFN 0 // 长文件名#define _MAX_LFN 255 // LFN缓冲区，LFN禁止时无效/* The _USE_LFN option switches the LFN feature.// 0: Disable LFN feature. _MAX_LFN has no effect./ 1: Enable LFN with static working buffer on the BSS. Always NOT thread-safe./ 启用LFN,并使用BSS上的静态缓冲区/ 2: Enable LFN with dynamic working buffer on the STACK. 使用堆上的动态缓冲区/ 3: Enable LFN with dynamic working buffer on the HEAP.// When enable the LFN feature, Unicode handling functions (option/unicode.c) must- / 如果使用LFN功能，optin/unicode.c必须添加到工程里，
/ be added to the project. The LFN working buffer occupies (_MAX_LFN + 1) * 2 bytes./ When use stack for the working buffer, take care on stack overflow. When use heap/ memory for the working buffer, memory management functions, ff_memalloc() and/ ff_memfree(), must be added to the project. */#define _LFN_UNICODE 0 // 编码类型/* This option switches character encoding on the API. (0:ANSI/OEM or 1:Unicode)/ To use Unicode string for the path name, enable LFN feature and set _LFN_UNICODE/ to 1. This option also affects behavior of string I/O functions. */#define _STRF_ENCODE // 字符串I/O功能编码，仅在_LFN_UNICODE为1时有效/* When _LFN_UNICODE is 1, this option selects the character encoding on the file to/ be read/written via string I/O functions, f_gets(), f_putc(), f_puts and f_printf().// 0: ANSI/OEM/ 1: UTF-16LE/ 2: UTF-16BE/ 3: UTF-8// When _LFN_UNICODE is 0, this option has no effect. */#define _FS_RPATH 0 // 相对路径/* This option configures relative path feature.// 0: Disable relative path feature and remove related functions./ 1: Enable relative path feature. f_chdir() and f_chdrive() are available./ 2: f_getcwd() function is available in addition to 1.// Note that directory items read via f_readdir() are affected by this option. *//*---------------------------------------------------------------------------// Drive/Volume Configurations // 驱动器/卷标配置/---------------------------------------------------------------------------*/#define _VOLUMES 1/* Number of volumes (logical drives) to be used. */#define _STR_VOLUME_ID 0#define _VOLUME_STRS "RAM","NAND","CF","SD1","SD2","USB1","USB2","USB3"/* _STR_VOLUME_ID option switches string volume ID feature./ When _STR_VOLUME_ID is set to 1, also pre-defined strings can be used as drive/ number in the path name. _VOLUME_STRS defines the drive ID strings for each/ logical drives. Number of items must be equal to _VOLUMES. Valid characters for/ the drive ID strings are: A-Z and 0-9. */#define _MULTI_PARTITION 0 // 多分区/* This option switches multi-partition feature. By default (0), each logical drive/ number is bound to the same physical drive number and only an FAT volume found on/ the physical drive will be mounted. When multi-partition feature is enabled (1),/ each logical drive number is bound to arbitrary physical drive and partition/ listed in the VolToPart[]. Also f_fdisk() funciton will be available. */#define _MIN_SS 512 // 配置支持的扇区大小，硬盘和SD卡多为512.flash 和 光盘可能需要更大的#define _MAX_SS 512/* These options configure the range of sector size to be supported. (512, 1024,/ 2048 or 4096) Always set both 512 for most systems, all type of memory cards and/ harddisk. But a larger value may be required for on-board flash memory and some/ type of optical media. When _MAX_SS is larger than _MIN_SS, FatFs is configured/ to variable sector size and GET_SECTOR_SIZE command must be implemented to the/ disk_ioctl() function. */#define _USE_TRIM 0/* This option switches ATA-TRIM feature. (0:Disable or 1:Enable)/ To enable Trim feature, also CTRL_TRIM command should be implemented to the/ disk_ioctl() function. */#define _FS_NOFSINFO 0 // 精确地剩余空间/* If you need to know correct free space on the FAT32 volume, set bit 0 of this/ option, and f_getfree() function at first time after volume mount will force/ a full FAT scan. Bit 1 controls the use of last allocated cluster number.// bit0=0: Use free cluster count in the FSINFO if available./ bit0=1: Do not trust free cluster count in the FSINFO./ bit1=0: Use last allocated cluster number in the FSINFO if available./ bit1=1: Do not trust last allocated cluster number in the FSINFO.*//*---------------------------------------------------------------------------// System Configurations 系统配置/---------------------------------------------------------------------------*/#define _FS_TINY 0 // 最小缓冲区/* This option switches tiny buffer configuration. (0:Normal or 1:Tiny)/ At the tiny configuration, size of the file object (FIL) is reduced _MAX_SS/ bytes. Instead of private sector buffer eliminated from the file object,/ common sector buffer in the file system object (FATFS) is used for the file/ data transfer. */#define _FS_NORTC 0 // 是否使用时间戳 0-使用，1-禁止#define _NORTC_MON 1 // 禁用时间戳是使用预设的时间戳#define _NORTC_MDAY 1#define _NORTC_YEAR 2015/* The _FS_NORTC option switches timestamp feature. If the system does not have/ an RTC function or valid timestamp is not needed, set _FS_NORTC to 1 to disable/ the timestamp feature. All objects modified by FatFs will have a fixed timestamp/ defined by _NORTC_MON, _NORTC_MDAY and _NORTC_YEAR./ When timestamp feature is enabled (_FS_NORTC == 0), get_fattime() function need/ to be added to the project to read current time form RTC. _NORTC_MON,/ _NORTC_MDAY and _NORTC_YEAR have no effect. 文件系统配置为只读时无效/ These options have no effect at read-only configuration (_FS_READONLY == 1). */#define _FS_LOCK 0/* The _FS_LOCK option switches file lock feature to control duplicated file open/ and illegal operation to open objects. This option must be 0 when _FS_READONLY/ is 1.// 0: Disable file lock feature. To avoid volume corruption, application program/ should avoid illegal open, remove and rename to the open objects./ >0: Enable file lock feature. The value defines how many files/sub-directories/ can be opened simultaneously under file lock control. Note that the file/ lock feature is independent of re-entrancy. */#define _FS_REENTRANT 0#define _FS_TIMEOUT 1000#define _SYNC_t HANDLE/* The _FS_REENTRANT option switches the re-entrancy (thread safe) of the FatFs/ module itself. Note that regardless of this option, file access to different/ volume is always re-entrant and volume control functions, f_mount(), f_mkfs()/ and f_fdisk() function, are always not re-entrant. Only file/directory access/ to the same volume is under control of this feature.// 0: Disable re-entrancy. _FS_TIMEOUT and _SYNC_t have no effect./ 1: Enable re-entrancy. Also user provided synchronization handlers,/ ff_req_grant(), ff_rel_grant(), ff_del_syncobj() and ff_cre_syncobj()/ function, must be added to the project. Samples are available in/ option/syscall.c.// The _FS_TIMEOUT defines timeout period in unit of time tick./ The _SYNC_t defines O/S dependent sync object type. e.g. HANDLE, ID, OS_EVENT*,/ SemaphoreHandle_t and etc.. A header file for O/S definitions needs to be/ included somewhere in the scope of ff.c. */#define _WORD_ACCESS 0 // 默认，一般不需要改/* The _WORD_ACCESS option is an only platform dependent option. It defines/ which access method is used to the word data on the FAT volume./ Byte-By-Byte模式，可以用在所有平台/ 0: Byte-by-byte access. Always compatible with all platforms./ 1: Word access. Do not choose this unless under both the following conditions.// * Address misaligned memory access is always allowed to ALL instructions./ * Byte order on the memory is little-endian.// If it is the case, _WORD_ACCESS can also be set to 1 to reduce code size./ Following table shows allowable settings of some type of processors.// ARM7TDMI 0 *2 ColdFire 0 *1 V850E 0 *2/ Cortex-M3 0 *3 Z80 0/1 V850ES 0/1/ Cortex-M0 0 *2 x86 0/1 TLCS-870 0/1/ AVR 0/1 RX600(LE) 0/1 TLCS-900 0/1/ AVR32 0 *1 RL78 0 *2 R32C 0 *2/ PIC18 0/1 SH-2 0 *1 M16C 0/1/ PIC24 0 *2 H8S 0 *1 MSP430 0 *2/ PIC32 0 *1 H8/300H 0 *1 8051 0/1// *1:Big-endian. 大端模式/ *2:Unaligned memory access is not supported. 不支持非对齐访问/ *3:Some compilers generate LDM/STM for mem_cpy function. 某些编译器生成LDM/STM内存拷贝功能*/
一般情况下，我们只要配置下面几项即可：
1 #define _FS_READONLY 如果不写入数据可以配置为只读
2 #define _USE_FIND 文件查找过滤
3 #define _CODE_PAGE 编码格式
4 #define _FS_NORTC 时间戳
5 #define _FS_RPATH 是否使用相对路径
6 #define _USE_LFN 0 是否使用长文件名