FAT32文件系统实现单片机MP3播放器 源代码.doc

#include sd.h #include ctype.h /* SD卡MP3播放器 源代码 */ sbit XDCS =P2^2; sbit DREQ =P3^5; sbit XRESET=P3^4; sbit XCS =P2^5; sbit CLK =P3^3; sbit DATA =P2^3; #define VOL_VALUE 0x0000 /* 分区记录结构 */ struct PartRecord { unsigned char Active; //0x80表示此分区有效 unsigned char StartHead; //分区的开始头 unsigned char StartCylSect[2];//开始柱面与扇区 unsigned char PartType; //分区类型 unsigned char EndHead; //分区的结束头 unsigned char EndCylSect[2]; //结束柱面与扇区 unsigned char StartLBA[4]; //分区的第一个扇区 unsigned char Size[4]; //分区的大小 }; /* 分区扇区（绝对0扇区）定义如下 */ struct PartSector { unsigned char PartCode[446]; //MBR的引导程序 struct PartRecord Part[4]; //4个分区记录 unsigned char BootSectSig0; unsigned char BootSectSig1; }; struct FAT32_FAT_Item { unsigned char Item[4]; }; struct FAT32_FAT { struct FAT32_FAT_Item Items[128]; }; /* FAT32中对BPB的定义如下 一共占用90个字节 */ struct FAT32_BPB { unsigned char BS_jmpBoot[3]; //跳转指令 offset: 0 unsigned char BS_OEMName[8]; // offset: 3 unsigned char BPB_BytesPerSec[2];//每扇区字节数 offset:11 unsigned char BPB_SecPerClus[1]; //每簇扇区数 offset:13 unsigned char BPB_RsvdSecCnt[2]; //保留扇区数目 offset:14 unsigned char BPB_NumFATs[1]; //此卷中FAT表数 offset:16 unsigned char BPB_RootEntCnt[2]; //FAT32为0 offset:17 unsigned char BPB_TotSec16[2]; //FAT32为0 offset:19 unsigned char BPB_Media[1]; //存储介质 offset:21 unsigned char BPB_FATSz16[2]; //FAT32为0 offset:22 unsigned char BPB_SecPerTrk[2]; //磁道扇区数 offset:24 unsigned char BPB_NumHeads[2]; //磁头数 offset:26 unsigned char BPB_HiddSec[4]; //FAT区前隐扇区数 offset:28 unsigned char BPB_TotSec32[4]; //该卷总扇区数 offset:32 unsigned char BPB_FATSz32[4]; //一个FAT表扇区数 offset:36 unsigned char BPB_ExtFlags[2]; //FAT32特有 offset:40 unsigned char BPB_FSVer[2]; //FAT32特有 offset:42 unsigned char BPB_RootClus[4]; //根目