diff --git a/software/platform/raspberry-pico-w/msc_disk.c b/software/platform/raspberry-pico-w/msc_disk.c
index 906f536..e88e04d 100644
--- a/software/platform/raspberry-pico-w/msc_disk.c
+++ b/software/platform/raspberry-pico-w/msc_disk.c
@@ -4,6 +4,7 @@
 
 #include "pico.h"
 #include "filesystem.h"
+#include "debug.h"
 
 // whether host does safe-eject
 static bool ejected = false;
@@ -75,6 +76,7 @@ bool tud_msc_start_stop_cb(uint8_t lun, uint8_t power_condition, bool start, boo
 }
 
 static uint8_t blockBuf[512];
+static uint8_t WrBlockBuf[512];
 
 #include "fs_task.h"
 #include "qor.h"
@@ -89,7 +91,14 @@ void msc_disk_initialize()
 void fs_read_cb(bool success)
 {
   (void)success;
-  static uint8_t dummy;
+  static const uint8_t dummy = 0x42;
+  qor_mbox_notify(&ReadFsMailBox, (void **)&dummy, QOR_MBOX_OPTION_SEND_BACK);
+}
+
+void fs_write_cb(bool success)
+{
+  (void)success;
+  static uint8_t dummy = 0x88;
   qor_mbox_notify(&ReadFsMailBox, (void **)&dummy, QOR_MBOX_OPTION_SEND_BACK);
 }
 
@@ -99,16 +108,17 @@ int32_t tud_msc_read10_cb(uint8_t lun, uint32_t lba, uint32_t offset, void *buff
 {
   (void)lun;
 
-  // out of ramdisk
-  // if (lba >= DISK_BLOCK_NUM)
-  //   return -1;
-
   fs_task_read_block(lba, blockBuf, fs_read_cb);
 
-  uint8_t *ev;
-  uint32_t res = qor_mbox_wait(&ReadFsMailBox, (void **)&ev, 200);
+  uint8_t *ev_ptr = NULL;
+  uint32_t res = qor_mbox_wait(&ReadFsMailBox, (void **)&ev_ptr, 200);
 
-  // printf("lba 0x%x, bufsize %d, offset %d\n",lba, bufsize, offset);
+  if (res != QOR_MBOX_OK)
+  {
+    return 0;
+  }
+
+  debug_printf("lba 0x%x, bufsize %d, offset %d\n", lba, bufsize, offset);
   // uint8_t const *addr = msc_disk[lba] + offset;
 
   uint8_t const *addr = blockBuf + offset;
@@ -129,7 +139,19 @@ bool tud_msc_is_writable_cb(uint8_t lun)
 int32_t tud_msc_write10_cb(uint8_t lun, uint32_t lba, uint32_t offset, uint8_t *buffer, uint32_t bufsize)
 {
   (void)lun;
-  printf("write - lba 0x%x, bufsize%d\n", lba, bufsize);
+  // debug_printf("write - lba 0x%x, bufsize%d\n", lba, bufsize);
+
+  memcpy(WrBlockBuf, buffer + offset, bufsize);
+
+  fs_task_write_block(lba, WrBlockBuf, fs_write_cb);
+
+  uint8_t *ev_ptr = NULL;
+
+  uint32_t res = qor_mbox_wait(&ReadFsMailBox, (void **)&ev_ptr, 200);
+  if (res != QOR_MBOX_OK)
+  {
+    return 0;
+  }
 
   return (int32_t)bufsize;
 }
diff --git a/software/platform/raspberry-pico-w/usb_descriptors.c b/software/platform/raspberry-pico-w/usb_descriptors.c
index f516ab9..5849633 100644
--- a/software/platform/raspberry-pico-w/usb_descriptors.c
+++ b/software/platform/raspberry-pico-w/usb_descriptors.c
@@ -1,6 +1,9 @@
 #include "tusb.h"
 #include "class/msc/msc.h"
 #include "device/usbd.h"
+
+#include "fs_task.h"
+
 /* A combination of interfaces must have a unique product id, since PC will save device driver after the first plug.
  * Same VID/PID with different interface e.g MSC (first), then CDC (later) will possibly cause system error on PC.
  *
@@ -43,6 +46,9 @@ tusb_desc_device_t const desc_device =
 
         .bNumConfigurations = 0x01};
 
+#include "debug.h"
+#include "usb_task.h"
+
 // Invoked when received GET DEVICE DESCRIPTOR
 // Application return pointer to descriptor
 uint8_t const *tud_descriptor_device_cb(void)
@@ -154,6 +160,8 @@ uint8_t const *tud_descriptor_configuration_cb(uint8_t index)
 //--------------------------------------------------------------------+
 
 /*
+Caractéristiques USB de la Lunii
+
 T:  Bus=03 Lev=03 Prnt=04 Port=00 Cnt=01 Dev#= 75 Spd=480 MxCh= 0
 D:  Ver= 2.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
 P:  Vendor=0c45 ProdID=6840 Rev=01.00
diff --git a/software/system/fs_task.c b/software/system/fs_task.c
index 4061187..40dbf2c 100644
--- a/software/system/fs_task.c
+++ b/software/system/fs_task.c
@@ -36,6 +36,7 @@ typedef enum
     FS_LOAD_INDEX,
     FS_LOAD_STORY,
     FS_READ_SDCARD_BLOCK,
+    FS_WRITE_SDCARD_BLOCK,
     FS_AUDIO_NEXT_SAMPLES
 } fs_state_t;
 
@@ -97,6 +98,18 @@ static void show_duration(uint32_t millisecondes)
     debug_printf("Temps : %d minutes, %d secondes, %d millisecondes\r\n", minutes, secondes, reste);
 }
 
+static bool UsbConnected = false;
+
+void fs_task_usb_connected()
+{
+    UsbConnected = true;
+}
+
+void fs_task_usb_disconnected()
+{
+    UsbConnected = true;
+}
+
 void FsTask(void *args)
 {
     ost_fs_event_t *message = NULL;
@@ -192,6 +205,14 @@ void FsTask(void *args)
                 }
                 break;
 
+            case FS_WRITE_SDCARD_BLOCK:
+                sdcard_sector_write(message->addr, message->mem);
+                if (message->cb != NULL)
+                {
+                    message->cb(true);
+                }
+                break;
+
             default:
                 break;
             }
@@ -215,6 +236,17 @@ void fs_task_read_block(uint32_t addr, uint8_t *block, fs_result_cb_t cb)
     qor_mbox_notify(&FsMailBox, (void **)&ReadBlockEv, QOR_MBOX_OPTION_SEND_BACK);
 }
 
+void fs_task_write_block(uint32_t addr, uint8_t *block, fs_result_cb_t cb)
+{
+    static ost_fs_event_t WriteBlockEv = {
+        .ev = FS_WRITE_SDCARD_BLOCK};
+
+    WriteBlockEv.mem = block;
+    WriteBlockEv.addr = addr;
+    WriteBlockEv.cb = cb;
+    qor_mbox_notify(&FsMailBox, (void **)&WriteBlockEv, QOR_MBOX_OPTION_SEND_BACK);
+}
+
 void fs_task_scan_index(fs_result_cb_t cb)
 {
     static ost_fs_event_t ScanIndexEv = {
diff --git a/software/system/fs_task.h b/software/system/fs_task.h
index 0cc7dc5..395b623 100644
--- a/software/system/fs_task.h
+++ b/software/system/fs_task.h
@@ -12,5 +12,8 @@ void fs_task_image_start(char *image);
 void fs_task_sound_start(char *sound);
 void fs_task_play_index();
 void fs_task_read_block(uint32_t addr, uint8_t *block, fs_result_cb_t cb);
+void fs_task_write_block(uint32_t addr, uint8_t *block, fs_result_cb_t cb);
+void fs_task_usb_connected();
+void fs_task_usb_disconnected();
 
 #endif // FS_TASK_H
diff --git a/software/system/usb_task.c b/software/system/usb_task.c
index 0343c4f..e511de8 100644
--- a/software/system/usb_task.c
+++ b/software/system/usb_task.c
@@ -27,10 +27,13 @@
 // ===========================================================================================================
 // DEFINITIONS
 // ===========================================================================================================
+
+#define USB_EV_CONNECTED 0x42
+
 typedef struct
 {
     uint8_t ev;
-} ost_hmi_event_t;
+} ost_usb_event_t;
 
 typedef enum
 {
@@ -48,9 +51,9 @@ static uint32_t UsbStack[4096];
 
 static qor_mbox_t UsbMailBox;
 
-static ost_hmi_event_t UsbEvent;
+static ost_usb_event_t UsbEvent;
 
-static ost_hmi_event_t *UsbQueue[10];
+static ost_usb_event_t *UsbQueue[10];
 
 static ost_system_state_t OstState = OST_SYS_WAIT_INDEX;
 
@@ -62,18 +65,40 @@ static ost_context_t OstContext;
 void UsbTask(void *args)
 {
 
-    ost_hmi_event_t *e = NULL;
+    ost_usb_event_t *message = NULL;
 
     // init device stack on configured roothub port
     tusb_init();
 
+    bool ConnectedState = false;
+    uint32_t res = 0;
+
     while (1)
     {
-        // tud_task(); // tinyusb device task
-        qor_sleep(10);
+        // res = qor_mbox_wait(&UsbMailBox, (void **)&message, 5);
+
+        // if (res == QOR_MBOX_OK)
+        // {
+        //     if (message->ev == USB_EV_CONNECTED)
+        //     {
+
+        //         ConnectedState = true;
+        //     }
+        // }
+
+        tud_task(); // tinyusb device task
+        qor_sleep(5);
     }
 }
 
+void usb_task_connected()
+{
+    static ost_usb_event_t message;
+
+    message.ev = USB_EV_CONNECTED;
+    qor_mbox_notify(&UsbMailBox, (void **)&message, QOR_MBOX_OPTION_SEND_BACK);
+}
+
 #include "msc_disk.h"
 
 void usb_task_initialize()
@@ -93,13 +118,17 @@ void usb_task_initialize()
 // Invoked when device is mounted
 void tud_mount_cb(void)
 {
+    debug_printf("[USB] Connected\r\n");
     // blink_interval_ms = BLINK_MOUNTED;
+    // fs_task_usb_connected();
 }
 
 // Invoked when device is unmounted
 void tud_umount_cb(void)
 {
     // blink_interval_ms = BLINK_NOT_MOUNTED;
+    debug_printf("[USB] Disconnected\r\n");
+    // fs_task_usb_disconnected();
 }
 
 // Invoked when usb bus is suspended
diff --git a/software/system/usb_task.h b/software/system/usb_task.h
index 248f492..421234b 100644
--- a/software/system/usb_task.h
+++ b/software/system/usb_task.h
@@ -4,5 +4,6 @@
 #include <stdint.h>
 
 void usb_task_initialize();
+void usb_task_connected();
 
 #endif // USB_TASK_H