--- Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Src/usbd_msc_scsi.c	(date 1511202099000)
+++ Middlewares/ST/STM32_USB_Device_Library/Class/MSC/Src/usbd_msc_scsi.c	(revision )
@@ -190,14 +190,27 @@
                    INVALID_CDB);
     return -1;
   }  
-  
-  if(((USBD_StorageTypeDef *)pdev->pUserData)->IsReady(lun) !=0 )
+
+  // XXX THIS SECTION IS MODIFIED FOR NOTIFY!
+  // https://www.microchip.com/forums/m401735.aspx
+  int8_t changeStatus = ((USBD_StorageTypeDef *)pdev->pUserData)->IsReady(lun);
+  if(changeStatus != 0)
   {
-    SCSI_SenseCode(pdev,
-                   lun,
-                   NOT_READY, 
-                   MEDIUM_NOT_PRESENT);
-    
+    if (changeStatus == -1)
+    {
+      SCSI_SenseCode(pdev,
+                     lun,
+                     UNIT_ATTENTION,
+                     MEDIUM_HAVE_CHANGED);
+    }
+    else
+    {
+      SCSI_SenseCode(pdev,
+                     lun,
+                     NOT_READY,
+                     MEDIUM_NOT_PRESENT);
+    }
+
     hmsc->bot_state = USBD_BOT_NO_DATA;
     return -1;
   }