diff --git a/build.py b/build.py
index 1c35589..b98113a 100644
--- a/build.py
+++ b/build.py
@@ -92,5 +92,5 @@ def linker(): #交叉编译链接
 if a != 0:
     exit(-1)
 
-os.system("qemu-system-i386 -kernel isodir\\sys\\kernel.elf")
+os.system("qemu-system-i386 -kernel isodir\\sys\\kernel.elf -drive format=qcow2,file=cpos.qcow2")
 
diff --git a/cpos.qcow2 b/cpos.qcow2
new file mode 100644
index 0000000..9907ff2
Binary files /dev/null and b/cpos.qcow2 differ
diff --git a/driver/disk.c b/driver/disk.c
new file mode 100644
index 0000000..c9551cd
--- /dev/null
+++ b/driver/disk.c
@@ -0,0 +1,73 @@
+#include "../include/disk.h"
+#include "../include/io.h"
+
+void wait_disk_ready()
+{
+    while (1)
+    {
+        int data = io_in8(0x1f7);
+        if ((data & 0x88) == 0x08) // 第3位为1表示硬盘控制器已准备好数据传输，第7位为1表示硬盘忙。
+        {
+            return;
+        }
+    }
+}
+
+void select_sector(int lba)
+{
+    io_out8(0x1f2, 1);
+    io_out8(0x1f3, lba);
+    io_out8(0x1f4, lba >> 8);
+    io_out8(0x1f5, lba >> 16);
+    io_out8(0x1f6, (((lba >> 24) & 0x0f) | 0xe0));
+}
+
+void read_disk_one_sector(int lba, unsigned int memory_addrress)
+{
+    while (io_in8(0x1f7) & 0x80)
+        ;
+    select_sector(lba);
+    io_out8(0x1f7, 0x20);
+    wait_disk_ready();
+    for (int i = 0; i < 256; i++)
+    {
+        short data = (short)io_in16(0x1f0);
+        *((short *)memory_addrress) = data;
+        memory_addrress += 2;
+    }
+}
+
+void write_disk_one_sertor(int lba, unsigned int memory_addrress)
+{
+    while (io_in8(0x1f7) & 0x80)
+        ;
+    select_sector(lba);
+    io_out8(0x1f7, 0x30);
+    wait_disk_ready();
+    for (int i = 0; i < 256; i++)
+    {
+        short data = *((short *)memory_addrress);
+        io_out16(0x1f0, data);
+        memory_addrress += 2;
+    }
+}
+
+void read_disk(int lba, int sector_count, unsigned int memory_addrress)
+{
+    for (int i = 0; i < sector_count; i++)
+    {
+        read_disk_one_sector(lba, memory_addrress);
+        lba++;
+        memory_addrress += 512;
+    }
+}
+
+void write_disk(int lba, int sector_count, unsigned int memory_addrress)
+{
+    for (int i = 0; i < sector_count; i++)
+    {
+        write_disk_one_sertor(lba, memory_addrress);
+        lba++;
+        memory_addrress += 512;
+    }
+}
\ No newline at end of file
diff --git a/include/disk.h b/include/disk.h
new file mode 100644
index 0000000..0350aef
--- /dev/null
+++ b/include/disk.h
@@ -0,0 +1,11 @@
+#ifndef CPOS_DISK_H
+#define CPOS_DISK_H
+
+void wait_disk_ready(); //不适用于SATA硬盘
+void select_sector(int lba);
+void read_disk_one_sector(int lba, unsigned int memory_addrress);
+void write_disk_one_sertor(int lba, unsigned int memory_addrress);
+void read_disk(int lba, int sector_count, unsigned int memory_addrress);
+void write_disk(int lba, int sector_count, unsigned int memory_addrress);
+
+#endif
\ No newline at end of file
diff --git a/include/fat16.h b/include/fat16.h
new file mode 100644
index 0000000..b842703
--- /dev/null
+++ b/include/fat16.h
@@ -0,0 +1,48 @@
+#ifndef CPOS_FAT16_H
+#define CPOS_FAT16_H
+
+#define SECTOR_SIZE 512
+#define FAT1_SECTORS 32                                     //FAT1占用扇区数
+#define ROOT_DIR_SECTORS 32                                 //根目录占用扇区数
+#define SECTOR_NUM_OF_FAT1_START 1                          //FAT1起始扇区号
+#define SECTOR_NUM_OF_ROOT_DIR_START 33                     //根目录起始扇区号
+#define SECTOR_NUM_OF_DATA_START 65                         //数据区起始扇区号，对应簇号为2。
+#define SECTOR_CLUSTER_BALANCE SECTOR_NUM_OF_DATA_START - 2 //簇号加上该值正好对应扇区号。
+#define MAX_FILE_NUM 16                                     //最大文件数
+
+// FAT16目录项结构(32B);
+struct File {
+    // 文件名 如果第一个字节为0xe5，代表这个文件已经被删除；如果第一个字节为0x00，代表这一段不包含任何文件名信息。
+    unsigned char name[8];
+    unsigned char ext[3]; // 扩展名
+    // 属性：bit0只读文件，bit1隐藏文件，bit2系统文件，bit3非文件信息(比如磁盘名称)，bit4目录，bit5文件。
+    unsigned char type; // 0x20 文件 | 0x10 目录
+    unsigned char reserve[10]; // 保留
+    unsigned short time;       // 最后一次写入时间
+    unsigned short date;       // 最后一次写入日期
+    unsigned short clustno;    // 起始簇号
+    unsigned int size;         // 文件大小
+};
+
+void read_root_dir_sector1(struct File *root_entries);
+void save_root_dir_sector1(struct File *root_entries);
+void read_one_cluster(unsigned short clustno, unsigned int memory_addrress);
+int read_root_dir(struct File *file_infos);
+void get_fat1(unsigned short *fat1);
+void save_fat1(unsigned short *fat1);
+void get_file_all_clustnos(unsigned short first_clustno, unsigned short *clustnos);
+void get_file_all_clustnos(unsigned short first_clustno, unsigned short *clustnos);
+void read_file(struct File *file, void *file_addr);
+void check_name_or_ext(char *str, int len);
+void check_name_and_ext(char *name, char *ext);
+void analyse_fullname(char *fullname, char *name, char *ext);
+int find_file(char *name, char *ext, struct File *const file);
+struct File *create_file(char *fullname);
+struct File *create_dir(char *fullname);
+struct File *open_file(char *fullname);
+void alter_file_name(struct File *file, char *new_fullname);
+void alter_dir_entry(struct File *file);
+void save_file(struct File *file, char *content);
+void delete_file(struct File *file);
+
+#endif
\ No newline at end of file
diff --git a/include/multiboot.h b/include/multiboot.h
index 89a7131..0b6abcd 100644
--- a/include/multiboot.h
+++ b/include/multiboot.h
@@ -3,7 +3,7 @@
 
 #include <stdint.h>
 
-#define VERSION "0.0.1"
+#define VERSION "0.0.2"
 #define LOADER_SAVE_GRAPHICS_ADDRESS 0xB8000 // loader中保存显存地址的地址
 #define VARTUAL_GRAPHICS_ADDRESS 0xe0000000
 
diff --git a/include/shell.h b/include/shell.h
index e47feff..bbd0594 100644
--- a/include/shell.h
+++ b/include/shell.h
@@ -10,5 +10,8 @@ void setup_shell();
 
 //内置命令
 void end_echo(int argc,char **argv);
+void cmd_ls();
+void cmd_cat(int argc,char **argv);
+void cmd_read(int argc,char **argv);
 
 #endif
\ No newline at end of file
diff --git a/isodir/sys/kernel.elf b/isodir/sys/kernel.elf
index 5357678..0205b33 100644
Binary files a/isodir/sys/kernel.elf and b/isodir/sys/kernel.elf differ
diff --git a/kernel/fat16.c b/kernel/fat16.c
new file mode 100644
index 0000000..1098416
--- /dev/null
+++ b/kernel/fat16.c
@@ -0,0 +1,357 @@
+#include "../include/fat16.h"
+#include "../include/memory.h"
+#include "../include/disk.h"
+
+void read_root_dir_sector1(struct File *root_entries)
+{
+    read_disk(SECTOR_NUM_OF_ROOT_DIR_START, 1, (unsigned int)root_entries);
+}
+
+void save_root_dir_sector1(struct File *root_entries)
+{
+    write_disk(SECTOR_NUM_OF_ROOT_DIR_START, 1, (unsigned int)root_entries);
+}
+
+void read_one_cluster(unsigned short clustno, unsigned int memory_addrress)
+{
+    read_disk(clustno + SECTOR_CLUSTER_BALANCE, 1, memory_addrress);
+}
+
+int read_root_dir(struct File *file_infos)
+{
+    struct File *root_entries = kmalloc(SECTOR_SIZE);
+    read_root_dir_sector1(root_entries);
+    int n = 0; // 记录文件数
+    for (int i = 0; i < MAX_FILE_NUM; i++)
+    {
+        if (root_entries[i].name[0] == 0)
+        {
+            break;
+        }
+        if (root_entries[i].name[0] != 0xe5)
+        {
+            file_infos[n] = root_entries[i];
+            n++;
+        }
+    }
+    kfree(root_entries);
+    return n;
+}
+
+void get_fat1(unsigned short *fat1)
+{
+    read_disk(SECTOR_NUM_OF_FAT1_START, FAT1_SECTORS, (unsigned int)fat1); // 将FAT1全部读取到内存中。
+}
+
+void save_fat1(unsigned short *fat1)
+{
+    write_disk(SECTOR_NUM_OF_FAT1_START, FAT1_SECTORS, (unsigned int)fat1); // 将FAT1全部写回到内存中。
+}
+
+void get_file_all_clustnos(unsigned short first_clustno, unsigned short *clustnos)
+{
+    unsigned short *fat1 = kmalloc(FAT1_SECTORS * SECTOR_SIZE);
+    get_fat1(fat1);
+    *clustnos = first_clustno;
+    while (1)
+    {
+        unsigned short clustno = *(fat1 + *clustnos);
+        clustnos++;
+        *clustnos = clustno;
+        if (clustno >= 0xfff8) // 大于等于0xfff8表示文件的最后一个簇
+        {
+            break;
+        }
+    }
+    kfree(fat1);
+}
+
+void read_file(struct File *file, void *file_addr)
+{
+    if (file->size == 0)
+    {
+        return;
+    }
+    int cluster_count = (file->size + 511) / 512;
+    unsigned short *clustnos = kmalloc(cluster_count * 2);
+    get_file_all_clustnos(file->clustno, clustnos);
+    for (int i = 0; i < cluster_count; i++)
+    {
+        read_one_cluster(clustnos[i], (unsigned int)file_addr);
+        file_addr += 512;
+    }
+    kfree(clustnos);
+}
+
+void check_name_or_ext(char *str, int len)
+{
+    for (int i = 0; i < len; i++)
+    {
+        if (str[i] == 0)
+        {
+            str[i] = ' ';
+        }
+        else if ('a' <= str[i] && str[i] <= 'z')
+        {
+            str[i] -= 0x20;
+        }
+    }
+}
+
+void check_name_and_ext(char *name, char *ext)
+{
+    check_name_or_ext(name, 8);
+    check_name_or_ext(ext, 3);
+}
+
+void analyse_fullname(char *fullname, char *name, char *ext)
+{
+    int ext_dot_index = -1;
+    for (int i = 11; i >= 0; i--)
+    {
+        if (fullname[i] == '.')
+        {
+            ext_dot_index = i;
+        }
+    }
+    if (ext_dot_index == -1) // 没有后缀名的情况
+    {
+        memcpy(name, fullname, 8);
+        memset(ext, ' ', 3);
+    }
+    else if (ext_dot_index == 0) // 没有文件名的情况
+    {
+        memset(name, ' ', 8);
+        memcpy(ext, fullname + 1, 3);
+    }
+    else
+    {
+        memcpy(name, fullname, ext_dot_index);
+        memcpy(ext, fullname + ext_dot_index + 1, 3);
+    }
+    check_name_and_ext(name, ext);
+}
+
+int find_file(char *name, char *ext, struct File *const file)
+{
+    struct File *root_entries = kmalloc(SECTOR_SIZE);
+    read_root_dir_sector1(root_entries);
+    int isfind = 0;
+    for (int i = 0; i < MAX_FILE_NUM; i++)
+    {
+        if (memcmp(root_entries[i].name, name, 8) == 0 && memcmp(root_entries[i].ext, ext, 3) == 0)
+        {
+            if (file != 0)
+            {
+                *file = root_entries[i];
+            }
+            isfind = 1;
+        }
+    }
+    kfree(root_entries);
+    return isfind;
+}
+
+struct File *create_dir(char *fullname){
+    char name[8] = {0};
+    char ext[3] = {0};
+    analyse_fullname(fullname, name, ext);
+    int isfind = find_file(name, ext, 0);
+    if (isfind) {
+        return 0; //文件已存在。
+    }
+
+    struct File *file = (struct File *) kmalloc(32);
+    memcpy(file->name, name, 8);
+    memcpy(file->ext, "   ", 3);
+    file->type = 0x10;
+    file->time = 0;
+    file->date = 0;
+    file->clustno = 0;
+    file->size = 0;
+
+    struct File *root_entries = kmalloc(SECTOR_SIZE);
+    read_root_dir_sector1(root_entries);
+    for (int i = 0; i < MAX_FILE_NUM; i++) {
+        if (root_entries[i].name[0] == 0 || root_entries[i].name[0] == 0xe5) { //找一个空闲的文件项存放。
+            root_entries[i] = *file;
+            break;
+        }
+    }
+    save_root_dir_sector1(root_entries);
+    kfree(root_entries);
+    return file;
+}
+
+struct File *create_file(char *fullname) {
+    char name[8] = {0};
+    char ext[3] = {0};
+    analyse_fullname(fullname, name, ext);
+    int isfind = find_file(name, ext, 0);
+    if (isfind) {
+        return 0; //文件已存在。
+    }
+
+    struct File *file = (struct File *) kmalloc(32);
+    memcpy(file->name, name, 8);
+    memcpy(file->ext, ext, 3);
+    file->type = 0x20;
+    file->time = 0;
+    file->date = 0;
+    file->clustno = 0;
+    file->size = 0;
+
+    struct File *root_entries = kmalloc(SECTOR_SIZE);
+    read_root_dir_sector1(root_entries);
+    for (int i = 0; i < MAX_FILE_NUM; i++) {
+        if (root_entries[i].name[0] == 0 || root_entries[i].name[0] == 0xe5) { //找一个空闲的文件项存放。
+            root_entries[i] = *file;
+            break;
+        }
+    }
+    save_root_dir_sector1(root_entries);
+
+    kfree(root_entries);
+    //open_file_task(file);
+    kfree(name);
+    kfree(ext);
+    return file;
+}
+
+struct File *open_file(char *fullname) {
+    char name[8] = {0};
+    char ext[3] = {0};
+    analyse_fullname(fullname, name, ext);
+    struct File *file = (struct File *) kmalloc(32);
+    int isfind = find_file(name, ext, file);
+    if (!isfind) {
+        kfree(file);
+        file = 0;
+    } else {
+        //set_opened_file(file);
+    }
+    return file;
+}
+
+void alter_file_name(struct File *file, char *new_fullname) {
+    char new_name[8] = {0};
+    char new_ext[3] = {0};
+    analyse_fullname(new_fullname, new_name, new_ext);
+    struct File *root_entries = kmalloc(SECTOR_SIZE);
+    read_root_dir_sector1(root_entries);
+    for (int i = 0; i < MAX_FILE_NUM; i++) {
+        if (memcmp(root_entries[i].name, file->name, 8) == 0 && memcmp(root_entries[i].ext, file->ext, 3) == 0) {
+            memcpy(root_entries[i].name, new_name, 8);
+            memcpy(root_entries[i].ext, new_ext, 3);
+        }
+    }
+    save_root_dir_sector1(root_entries);
+    kfree(root_entries);
+}
+
+void alter_dir_entry(struct File *file) {
+    struct File *root_entries = kmalloc(SECTOR_SIZE);
+    read_root_dir_sector1(root_entries);
+    for (int i = 0; i < MAX_FILE_NUM; i++) {
+        if (memcmp(root_entries[i].name, file->name, 8) == 0 && memcmp(root_entries[i].ext, file->ext, 3) == 0) {
+            root_entries[i] = *file;
+        }
+    }
+    save_root_dir_sector1(root_entries);
+    kfree(root_entries);
+}
+
+void save_file(struct File *file, char *content) {
+    unsigned int file_size = strlen(content); //内容大小
+    if (file_size == 0 && file->size == 0) {
+        return;
+    }
+    file->size = file_size;
+    int sector_num = (file_size + 511) / 512; //将要占用的扇区数
+    unsigned short *fat1 = kmalloc(FAT1_SECTORS * SECTOR_SIZE);
+    get_fat1(fat1);
+    unsigned short clustno = file->clustno;
+    unsigned short next_clustno;
+    if (file->clustno == 0) //第一次写入
+    {
+        clustno = 2; //可用簇号从2开始
+        while (1) {
+            if (*(fat1 + clustno) == 0) //空闲簇号
+            {
+                file->clustno = clustno; //分配起始簇号
+                break;
+            } else {
+                clustno++;
+            }
+        }
+    }
+    int i = 0;
+    while (1) {
+        write_disk(SECTOR_CLUSTER_BALANCE + clustno, 1, (unsigned int) content);
+        if (i == sector_num - 1) { //已写完最后一扇区。
+            break;
+        }
+        i++;
+        content += 512;
+        next_clustno = *(fat1 + clustno);
+        if (next_clustno == 0 || next_clustno >= 0xfff8) { //寻找下一个可用簇号
+            next_clustno = clustno + 1;
+            while (1) {
+                if (*(fat1 + next_clustno) == 0) {
+                    *(fat1 + clustno) = next_clustno;
+                    break;
+                } else {
+                    next_clustno++;
+                }
+            }
+        }
+        clustno = next_clustno;
+    }
+    next_clustno = *(fat1 + clustno);
+    *(fat1 + clustno) = 0xffff; //0xfff8~0xffff表示文件结束，没有下一个簇了。
+    //如果本次写入的内容比上次的少，上次用过的簇号本次用不完，以下将剩下的簇号清零处理。
+    if (1 < next_clustno && next_clustno < 0xfff0) {
+        while (1) {
+            clustno = next_clustno;
+            next_clustno = *(fat1 + clustno);
+            *(fat1 + clustno) = 0;
+            if (next_clustno >= 0xfff8) {
+                break;
+            }
+        }
+    }
+    alter_dir_entry(file);
+    save_fat1(fat1);
+    kfree(fat1);
+}
+
+void delete_file(struct File *file) {
+    //1.标记目录项为已删除。
+    struct File *root_entries = kmalloc(SECTOR_SIZE);
+    read_root_dir_sector1(root_entries);
+    for (int i = 0; i < MAX_FILE_NUM; i++) {
+        if (memcmp(root_entries[i].name, file->name, 8) == 0 && memcmp(root_entries[i].ext, file->ext, 3) == 0) {
+            root_entries[i].name[0] = 0xe5;
+            break;
+        }
+    }
+    save_root_dir_sector1(root_entries);
+    kfree(root_entries);
+    if (file->clustno == 0) {
+        return;
+    }
+    unsigned short *fat1 = kmalloc(FAT1_SECTORS * SECTOR_SIZE);
+    get_fat1(fat1);
+    unsigned short clustno = file->clustno;
+    unsigned short next_clustno = 0;
+    while (1) {
+        next_clustno = *(fat1 + clustno);
+        *(fat1 + clustno) = 0;
+        if (next_clustno >= 0xfff8) {
+            break;
+        }
+        clustno = next_clustno;
+    }
+    save_fat1(fat1);
+    kfree(fat1);
+}
\ No newline at end of file
diff --git a/sysapp/shell.c b/sysapp/shell.c
index f61251b..cf18628 100644
--- a/sysapp/shell.c
+++ b/sysapp/shell.c
@@ -5,6 +5,8 @@
 #include "../include/keyboard.h"
 #include "../include/io.h"
 #include "../include/common.h"
+#include "../include/fat16.h"
+#include "../include/memory.h"
 
 extern Queue *key_char_queue;
 
@@ -78,6 +80,59 @@ void cmd_echo(int argc,char **argv)
     vga_putchar('\n');
 }
 
+void cmd_ls()
+{
+    struct File *root = (struct File*) kmalloc(sizeof(struct File) * MAX_FILE_NUM);
+    int files = read_root_dir(root);
+    int index = 0,size = 0;
+    
+    for (int i = 0; i < files; ++i)
+    {
+        struct File file = root[i];
+        if(!strcmp(file.name,"\0")) continue;
+        printf("%s   %s  %d\n",file.name,file.type == 0x20 ? "<FILE>" : " <DIR> ",file.size);
+        index++;
+        size += file.size;
+    }
+    printf("    All File: %d  | All Size: %d\n",index,size);
+    kfree(root);
+}
+
+void cmd_cat(int argc,char **argv)
+{
+    if(argc <= 2) {
+        printf("[Shell-CAT]: If there are too few parameters, please specify the filename and data.");
+        return;
+    }
+    struct File *file = open_file(argv[1]);
+    if(file == NULL){
+        printf("[Shell-CAT]: Not found [%s] \n",argv[1]);
+        return;
+    }
+
+    save_file(file,argv[2]);
+    kfree(file);
+}
+
+void cmd_read(int argc,char **argv)
+{
+    if(argc == 1) {
+        printf("[Shell-READ]: If there are too few parameters, please specify the filename");
+        return;
+    }
+    struct File *file = open_file(argv[1]);
+    char* buffer = (char*) kmalloc(4096);
+    if(file == NULL){
+        printf("[Shell-READ]: Not found [%s] \n",argv[1]);
+        return;
+    }
+
+    read_file(file,buffer);
+    printf("%s\n",buffer);
+    kfree(buffer);
+    kfree(file);
+}
+
 void setup_shell()
 {
     vga_clear();
@@ -106,12 +161,21 @@ void setup_shell()
             cmd_echo(argc,argv);
         else if(!strcmp("clear",argv[0]))
             vga_clear();
+        else if(!strcmp("ls",argv[0]))
+            cmd_ls();
+        else if(!strcmp("cat",argv[0]))
+            cmd_cat(argc,argv);
+        else if(!strcmp("read",argv[0]))
+            cmd_read(argc,argv);
         else if(!strcmp("help",argv[0])||!strcmp("?",argv[0])||!strcmp("h",argv[0]))
         {
             vga_writestring("-=[CrashPowerShell Helper]=-\n");
-            vga_writestring("help ? h   empty   Print shell help info.\n");
-            vga_writestring("version    empty   Print os version.\n");
+            vga_writestring("help ? h   |empty  Print shell help info.\n");
+            vga_writestring("version    |empty  Print os version.\n");
             vga_writestring("echo       <msg>   Print message.\n");
+            vga_writestring("ls         |empty  List all files.\n");
+            vga_writestring("cat <name> <data>  Edit a file\n");
+            vga_writestring("read       <name>  Read a file\n");
         }
         else printf("[Shell]: Unknown command '%s'.\n",argv[0]);
     }
diff --git a/target/disk.o b/target/disk.o
new file mode 100644
index 0000000..1157e27
Binary files /dev/null and b/target/disk.o differ
diff --git a/target/fat16.o b/target/fat16.o
new file mode 100644
index 0000000..75ba598
Binary files /dev/null and b/target/fat16.o differ
diff --git a/target/shell.o b/target/shell.o
index 209c228..fa15757 100644
Binary files a/target/shell.o and b/target/shell.o differ