diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5996a9d..fab5564 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -21,6 +21,7 @@ set(SOURCES
   src/menu/info.c
   src/menu/fat.c
   src/menu/list.c
+  src/menu/test.c
 
   #utils
   src/utils/fs_table.c
diff --git a/include/fsctl/fugue/bits/dirent.h b/include/fsctl/fugue/bits/dirent.h
index ecaf2ce..8c67406 100644
--- a/include/fsctl/fugue/bits/dirent.h
+++ b/include/fsctl/fugue/bits/dirent.h
@@ -18,6 +18,7 @@ struct fugue_dirent
     /* low-level information */
     struct {
         fugue_fs_t fs;
+        int lfn_prev_idx;
     } _private;
 
 };
diff --git a/include/fsctl/fugue/bits/fat.h b/include/fsctl/fugue/bits/fat.h
index 61738a9..38cd6b0 100644
--- a/include/fsctl/fugue/bits/fat.h
+++ b/include/fsctl/fugue/bits/fat.h
@@ -65,11 +65,11 @@ struct fugue_fat_dir
 struct fugue_fat_dir_name
 {
     struct {
-        uint8_t         :2;
+        uint8_t _low0   :1; // must be 0
         uint8_t last    :1;
-        uint8_t         :1;
-        uint8_t id      :4;
-    } DIR_Secquence;
+        uint8_t _low1   :1; // must be 0
+        uint8_t id      :5;
+    } DIR_Sequence;
     uint16_t DIR_Char0;
     uint16_t DIR_Char1;
     uint16_t DIR_Char2;
diff --git a/include/fsctl/fugue/bits/file.h b/include/fsctl/fugue/bits/file.h
index 44025dc..baeb586 100644
--- a/include/fsctl/fugue/bits/file.h
+++ b/include/fsctl/fugue/bits/file.h
@@ -12,6 +12,7 @@
 struct fugue_file
 {
     char name[210];
+    size_t name_len;
     int type;
     uint32_t size;
 };
diff --git a/include/fsctl/menu.h b/include/fsctl/menu.h
index bd04faa..c458834 100644
--- a/include/fsctl/menu.h
+++ b/include/fsctl/menu.h
@@ -2,3 +2,4 @@
 #include "fsctl/menu/rom.h"
 #include "fsctl/menu/info.h"
 #include "fsctl/menu/list.h"
+#include "fsctl/menu/test.h"
diff --git a/include/fsctl/menu/test.h b/include/fsctl/menu/test.h
new file mode 100644
index 0000000..854a747
--- /dev/null
+++ b/include/fsctl/menu/test.h
@@ -0,0 +1,13 @@
+#ifndef FSCTL_MENU_TEST_H
+#define FSCTL_MENU_TEST_H 1
+
+/* test_menu_init() : init menu */
+extern void test_menu_init(void);
+
+/* test_menu_display() : display menu */
+extern void test_menu_display(void);
+
+/* test_menu_keyboard() : handle keyboard */
+extern void test_menu_keyboard(int key);
+
+#endif /* FSCTL_MENU_TEST_H */
diff --git a/src/fugue/core/dirent.c b/src/fugue/core/dirent.c
index 125bd0f..6a8098d 100644
--- a/src/fugue/core/dirent.c
+++ b/src/fugue/core/dirent.c
@@ -29,6 +29,23 @@ static uint8_t _fugue_dirent_checksum(uintptr_t directory)
     return checksum;
 }
 
+/* _fugue_dirent_frag_dump() : decode name fragment */
+static int _fugue_dirent_frag_dump(fugue_file_t *file, uint8_t *frag, int n)
+{
+    while (--n >= 0)
+    {
+        file->name[file->name_len] = frag[0];
+        if ((frag[0] & 0x80) != 0) {
+            file->name[file->name_len] = frag[1];
+            file->name_len += 1;
+        }
+        file->name_len += 1;
+        frag = &frag[2];
+    }
+    file->name[file->name_len] = '\0';
+    return 0;
+}
+
 //---
 // Public
 //---
@@ -39,7 +56,7 @@ int fugue_dirent_init(fugue_dirent_t *dirent, fugue_fs_t *fs)
     if (fs == NULL || dirent == NULL)
         return -1;
     memset(dirent, 0x00, sizeof(fugue_dirent_t));
-    memcpy(&dirent->_private.fs, &fs, sizeof(fugue_fs_t));
+    memcpy(&dirent->_private.fs, fs, sizeof(fugue_fs_t));
     dirent->current_dir_addr   = (uintptr_t)fs->_private.root;
     dirent->cluster_addr_start = (uintptr_t)fs->_private.root;
     dirent->cluster_addr_end   = (uintptr_t)fs->_private.root;
@@ -86,24 +103,49 @@ int fugue_dirent_name_fetch(
     // check directory block validity
     //---
 
-    if (lfn->DIR_Attr != FUGUE_DIR_ATTR_LFN)
+    if (lfn->DIR_Attr != FUGUE_DIR_ATTR_LFN) {
+        fugue_logger_write(log, "[WARN] %p: LFN type error\n", lfn);
         return -1;
-    if (lfn->DIR_Type != 0x00)
+    }
+    if (lfn->DIR_Type != 0x00) {
+        fugue_logger_write(log, "[WARN] %p: LFN attribute error\n", lfn);
         return -2;
-    if (lfn->DIR_FstClus != 0x0000)
+    }
+    if (lfn->DIR_FstClus != 0x0000) {
+        fugue_logger_write(log, "[WARN] %p: cluster info error\n", lfn);
         return -3;
-    //TODO : check Secquence validity
+    }
+    if (lfn->DIR_Sequence._low0 != 0 || lfn->DIR_Sequence._low1 != 0) {
+        fugue_logger_write(log, "[WARN] %p: dirty sequence\n", lfn);
+        return -4;
+    }
     if (lfn->checksum != _fugue_dirent_checksum(dirent->current_dir_addr)) {
-        fugue_logger_write(log, "[WARN] checksum error at %p", lfn);
+        fugue_logger_write(log, "[WARN] %p: checksum error\n", lfn);
         return -5;
     }
 
+    //---
+    // check sequence validity
+    //---
+
+    if (lfn->DIR_Sequence.last != 0)
+    {
+        if (dirent->_private.lfn_prev_idx != 0)
+            fugue_logger_write(log, "[WARN] %p: multiple LFN entry\n", lfn);
+        dirent->_private.lfn_prev_idx = lfn->DIR_Sequence.id + 1;
+    }
+    if (dirent->_private.lfn_prev_idx != lfn->DIR_Sequence.id + 1) {
+        fugue_logger_write(log, "[WARN] %p: LFN sequence error\n", lfn);
+        return -6;
+    }
+    dirent->_private.lfn_prev_idx = lfn->DIR_Sequence.id;
+
     //---
     // Dump name fragment
     //---
 
-    //TODO: dump
-    (void)file;
-    fugue_logger_write(log, "[ERR] name dump error at %p", lfn);
+    _fugue_dirent_frag_dump(file, (uint8_t*)&lfn->DIR_Char0, 5);
+    _fugue_dirent_frag_dump(file, (uint8_t*)&lfn->DIR_Char5, 5);
+    _fugue_dirent_frag_dump(file, (uint8_t*)&lfn->DIR_Char11,2);
     return -1;
 }
diff --git a/src/fugue/dir.c b/src/fugue/dir.c
index 7a21782..5381c09 100644
--- a/src/fugue/dir.c
+++ b/src/fugue/dir.c
@@ -3,6 +3,7 @@
 #include "fsctl/fugue.h"
 #include "fsctl/fugue/bits/fat.h"
 #include "fsctl/fugue/dirent.h"
+#include "fsctl/fugue/logger.h"
 #include "fsctl/fugue/utils.h"
 #include "fsctl/utils/fs_table.h"
 
@@ -31,6 +32,7 @@ int fugue_fs_readdir(fugue_dirent_t *dirent, fugue_file_t *file)
 {
     struct fugue_fat_dir *dir;
     fugue_dirent_t dirent_backup;
+    fugue_logger_t *log;
     bool error;
     bool vfat;
 
@@ -43,6 +45,7 @@ int fugue_fs_readdir(fugue_dirent_t *dirent, fugue_file_t *file)
 
     memset(file, 0x00, sizeof(fugue_file_t));
     memcpy(&dirent_backup, dirent, sizeof(fugue_dirent_t));
+    log = dirent->_private.fs._private.logger;
 
     vfat = false;
     error = false;
@@ -63,7 +66,7 @@ int fugue_fs_readdir(fugue_dirent_t *dirent, fugue_file_t *file)
         {
             /* handle free directory */
             case 0x00:
-                //fugue_logger_warn("opendir: wierd empty directory block  ")
+                fugue_logger_write(log, "[WARN] opendir: empty dir block\n");
                 error = true;
                 continue;
 
@@ -73,8 +76,13 @@ int fugue_fs_readdir(fugue_dirent_t *dirent, fugue_file_t *file)
                     memcpy(file->name, ".", 2);
                 if (memcmp(dir->DIR_Name, ".. ", 3) == 0)
                     memcpy(file->name, "..", 3);
-                if (vfat == true)
-                    //fugue_logger_warn("opendir: wierd directory block  ")
+                if (vfat == true) {
+                    fugue_logger_write(
+                        log,
+                        "[WARN] %p:opendir: wierd dir block layout\n",
+                        dir
+                    );
+                }
                 file->type = FUGUE_FILE_TYPE_DIR;
                 file->size = FAT_LONG(dir->DIR_FileSize);
                 return 0;
@@ -82,7 +90,11 @@ int fugue_fs_readdir(fugue_dirent_t *dirent, fugue_file_t *file)
             /* removed entry */
             case 0x05:
             case 0xe5:
-                //fugue_logger_notice("opendir : removed entry");
+                fugue_logger_write(
+                    log,
+                    "[NOTICE] %p:opendir : removed entry\n",
+                    dir
+                );
                 memset(file, 0x00, sizeof(fugue_file_t));
                 vfat = false;
                 continue;
@@ -114,7 +126,11 @@ int fugue_fs_readdir(fugue_dirent_t *dirent, fugue_file_t *file)
 
             /* other attribute not handled */
             default:
-                //fugue_logger_warn("opendir : unsupported attribute ")
+                fugue_logger_write(
+                    log,
+                    "[WARN] %p:opendir : KO attr %02x\n",
+                    dir, dir->DIR_Attr
+                );
                 error = true;
                 break;
         }
diff --git a/src/main.c b/src/main.c
index 4a04643..15c582c 100644
--- a/src/main.c
+++ b/src/main.c
@@ -17,6 +17,7 @@ int main(void)
     info_menu_init();
     fat_menu_init();
     list_menu_init();
+    test_menu_init();
 
     tab = 0;
     while (1)
@@ -26,6 +27,7 @@ int main(void)
         if (tab == 1) { info_menu_display(); }
         if (tab == 2) { fat_menu_display();  }
         if (tab == 3) { list_menu_display(); }
+        if (tab == 4) { test_menu_display(); }
         dupdate();
 
         switch (key = getkey().key)
@@ -42,11 +44,15 @@ int main(void)
             case KEY_F4:
                 tab = 3;
                 break;
+            case KEY_F5:
+                tab = 4;
+                break;
             default:
                 if (tab == 0) { rom_menu_keyboard(key);  }
                 if (tab == 1) { info_menu_keyboard(key); }
                 if (tab == 2) { fat_menu_keyboard(key);  }
                 if (tab == 3) { list_menu_keyboard(key); }
+                if (tab == 4) { test_menu_keyboard(key); }
         }
     }
 
diff --git a/src/menu/info.c b/src/menu/info.c
index 23c9dc2..38446be 100644
--- a/src/menu/info.c
+++ b/src/menu/info.c
@@ -90,11 +90,15 @@ void info_menu_display(void)
         dline(391, 1 + y_start, 391, y_start + y_size, C_BLACK);
         dline(393,           0, 393,              190, C_BLACK);
     }
+    if (line_nb == 0)
+    {
+        dtext(1, 15, C_BLACK, "No logs for now...");
+    }
 
-    dprint(300, 15, C_BLACK, "start=%d", logs_line_start);
-    dprint(300, 26, C_BLACK, "line_nb=%d", line_nb);
 
 #if 0
+    dprint(300, 15, C_BLACK, "start=%d", logs_line_start);
+    dprint(300, 26, C_BLACK, "line_nb=%d", line_nb);
     int y = 0;
     _printXY(0, ++y, "FS type = %s", fs.props.type);
     _printXY(0, ++y, "capacity = %d", fs.props.capacity);
diff --git a/src/menu/test.c b/src/menu/test.c
new file mode 100644
index 0000000..5c05211
--- /dev/null
+++ b/src/menu/test.c
@@ -0,0 +1,128 @@
+#include "fsctl/menu.h"
+#include "fsctl/fugue.h"
+#include "fsctl/utils/fs_table.h"
+#include "fsctl/utils/display.h"
+
+//---
+// Internal
+//---
+
+/* internal information */
+static int test_selected;
+static int __find_ls;
+static int __find_lb;
+static int __find_fs;
+static int __find_fb;
+
+/* test_search() : search Fugue entry using sector */
+static void __test_search(
+    int *info,
+    uintptr_t start,
+    uintptr_t end,
+    size_t block
+) {
+    uintptr_t saved_start;
+    fugue_fs_t fs;
+    int counter;
+
+    dclear(C_WHITE);
+    _printXY(0, 0, "search from %p...", start);
+    dupdate();
+
+    counter = 0;
+    saved_start = start;
+    while (start < end)
+    {
+        if (fugue_fs_mount(&fs, (void *)start) == 0) {
+            dclear(C_WHITE);
+            _printXY(0, 0, "search from %p...", saved_start);
+            _printXY(0, 1, "- found = %d", counter);
+            dupdate();
+            *info += 1;
+        }
+        start += block;
+    }
+
+    dclear(C_WHITE);
+}
+
+/* test_search_sector() : search Fugue entry using sector */
+static void test_search_sector(int *info, uintptr_t start, uintptr_t end)
+{
+    __test_search(info, start, end, 512);
+}
+
+/* test_search_byte() : search Fugue entry using byte */
+static void test_search_byte(int *info, uintptr_t start, uintptr_t end)
+{
+    __test_search(info, start, end, 1);
+}
+
+//---
+// Public
+//---
+
+/* test_menu_init() : init menu */
+void test_menu_init(void)
+{
+    test_selected = -1;
+    __find_ls = 0;
+    __find_lb = 0;
+    __find_fs = 0;
+    __find_fb = 0;
+}
+
+/* test_menu_display() : display menu */
+void test_menu_display(void)
+{
+    int y;
+
+    y = 0;
+    switch(test_selected)
+    {
+        case 1:
+            test_search_sector(&__find_ls, 0xa1000000, 0xa2000000);
+            break;
+        case 2:
+            test_search_byte(&__find_ls, 0xa1000000, 0xa2000000);
+            break;
+        case 3:
+            test_search_sector(&__find_ls, 0xa0000000, 0xa1000000);
+            break;
+        case 4:
+            test_search_byte(&__find_ls, 0xa0000000, 0xa1000000);
+            break;
+    }
+    test_selected = -1;
+
+    _printXY(0, ++y, "[1] last 16Mo entry search (sector)");
+    _printXY(0, ++y, "[2] last 16Mo entry search (byte)");
+    _printXY(0, ++y, "[3] first 16Mo entry search (sector)");
+    _printXY(0, ++y, "[4] first 16Mo entry search (byte)");
+    _printXY(0, ++y, "");
+    _printXY(0, ++y, "");
+    _printXY(0, ++y, "last 16Mo sector found = %d", __find_ls);
+    _printXY(0, ++y, "last 16Mo byte found = %d", __find_lb);
+    _printXY(0, ++y, "first 16Mo sector found = %d", __find_fs);
+    _printXY(0, ++y, "first 16Mo byte found = %d", __find_fb);
+}
+
+/* test_menu_keyboard() : handle keyboard */
+void test_menu_keyboard(int key)
+{
+    switch (key)
+    {
+        case KEY_1:
+            test_selected = 1;
+            break;
+        case KEY_2:
+            test_selected = 2;
+            break;
+        case KEY_3:
+            test_selected = 3;
+            break;
+        case KEY_4:
+            test_selected = 4;
+            break;
+    }
+}