diff --git a/tinyusb/class/msc/msc_device.c b/tinyusb/class/msc/msc_device.c
index 73af4fd87..9da51a910 100644
--- a/tinyusb/class/msc/msc_device.c
+++ b/tinyusb/class/msc/msc_device.c
@@ -40,10 +40,6 @@
 
 #if (MODE_DEVICE_SUPPORTED && CFG_TUD_MSC)
 
-#if CFG_TUD_MSC_MAXLUN == 0 || CFG_TUD_MSC_MAXLUN > 16
-#error MSC Device: Incorrect setting of MAX LUN
-#endif
-
 #define _TINY_USB_SOURCE_FILE_
 //--------------------------------------------------------------------+
 // INCLUDE
@@ -63,9 +59,6 @@ enum
 };
 
 typedef struct {
-  // buffer for scsi's response other than read10 & write10.
-  // NOTE should be multiple of 64 to be compatible with lpc11/13u
-  uint8_t scsi_data[64];
   CFG_TUSB_MEM_ALIGN msc_cbw_t  cbw;
 
 #if defined (__ICCARM__) && (CFG_TUSB_MCU == OPT_MCU_LPC11UXX || CFG_TUSB_MCU == OPT_MCU_LPC13UXX)
@@ -74,10 +67,11 @@ typedef struct {
 
   CFG_TUSB_MEM_ALIGN msc_csw_t csw;
 
-  uint8_t interface_num;
-  uint8_t ep_in, ep_out;
+  uint8_t  interface_num;
+  uint8_t  ep_in;
+  uint8_t  ep_out;
 
-  uint8_t stage;
+  uint8_t  stage;
   uint16_t data_len;
   uint16_t xferred_len; // numbered of bytes transferred so far in the Data Stage
 }mscd_interface_t;
@@ -156,10 +150,9 @@ tusb_error_t mscd_control_request_st(uint8_t rhport, tusb_control_request_t cons
   }
   else if (MSC_REQUEST_GET_MAX_LUN == p_request->bRequest)
   {
-    // Note: lpc11/13u need xfer data's address to be aligned 64 -> make use of scsi_data instead of using max_lun directly
     // returned MAX LUN is minus 1 by specs
-    p_msc->scsi_data[0] = CFG_TUD_MSC_MAXLUN-1;
-    usbd_control_xfer_st(rhport, p_request->bmRequestType_bit.direction, p_msc->scsi_data, 1);
+    _mscd_buf[0] = CFG_TUD_MSC_MAXLUN-1;
+    usbd_control_xfer_st(rhport, p_request->bmRequestType_bit.direction, _mscd_buf, 1);
   }else
   {
     dcd_control_stall(rhport); // stall unsupported request
@@ -209,24 +202,23 @@ tusb_error_t mscd_xfer_cb(uint8_t rhport, uint8_t ep_addr, tusb_event_t event, u
 
         if ( p_cbw->xfer_bytes == 0)
         {
-          p_csw->status = tud_msc_scsi_cb(rhport, p_cbw->lun, p_cbw->command, p_msc->scsi_data, &p_msc->data_len) ? MSC_CSW_STATUS_PASSED : MSC_CSW_STATUS_FAILED;
+          p_csw->status = tud_msc_scsi_cb(rhport, p_cbw->lun, p_cbw->command, NULL, &p_msc->data_len) ? MSC_CSW_STATUS_PASSED : MSC_CSW_STATUS_FAILED;
           p_msc->stage  = MSC_STAGE_STATUS;
         }
         else if ( !BIT_TEST_(p_cbw->dir, 7) )
         {
-          TU_ASSERT( sizeof(p_msc->scsi_data) >= p_msc->data_len, TUSB_ERROR_NOT_ENOUGH_MEMORY); // needs to increase size for scsi_data
-          TU_ASSERT( dcd_edpt_xfer(rhport, p_msc->ep_out, p_msc->scsi_data, p_msc->data_len), TUSB_ERROR_DCD_EDPT_XFER );
+          // OUT transfer
+          TU_ASSERT( dcd_edpt_xfer(rhport, p_msc->ep_out, _mscd_buf, p_msc->data_len), TUSB_ERROR_DCD_EDPT_XFER );
         }
         else
         {
-          p_csw->status = tud_msc_scsi_cb(rhport, p_cbw->lun, p_cbw->command, p_msc->scsi_data, &p_msc->data_len) ? MSC_CSW_STATUS_PASSED : MSC_CSW_STATUS_FAILED;
+          p_csw->status = tud_msc_scsi_cb(rhport, p_cbw->lun, p_cbw->command, _mscd_buf, &p_msc->data_len) ? MSC_CSW_STATUS_PASSED : MSC_CSW_STATUS_FAILED;
 
           TU_ASSERT( p_cbw->xfer_bytes >= p_msc->data_len, TUSB_ERROR_INVALID_PARA ); // cannot return more than host expect
-          TU_ASSERT( sizeof(p_msc->scsi_data) >= p_msc->data_len, TUSB_ERROR_NOT_ENOUGH_MEMORY); // needs to increase size for scsi_data
 
           if ( p_msc->data_len )
           {
-            TU_ASSERT( dcd_edpt_xfer(rhport, p_msc->ep_in, p_msc->scsi_data, p_msc->data_len), TUSB_ERROR_DCD_EDPT_XFER );
+            TU_ASSERT( dcd_edpt_xfer(rhport, p_msc->ep_in, _mscd_buf, p_msc->data_len), TUSB_ERROR_DCD_EDPT_XFER );
           }else
           {
             // application does not provide data to response --> possibly unsupported SCSI command
@@ -252,7 +244,7 @@ tusb_error_t mscd_xfer_cb(uint8_t rhport, uint8_t ep_addr, tusb_event_t event, u
         }
         else
         {
-          p_csw->status = tud_msc_scsi_cb(rhport, p_cbw->lun, p_cbw->command, p_msc->scsi_data, &p_msc->data_len) ? MSC_CSW_STATUS_PASSED : MSC_CSW_STATUS_FAILED;
+          p_csw->status = tud_msc_scsi_cb(rhport, p_cbw->lun, p_cbw->command, _mscd_buf, &p_msc->data_len) ? MSC_CSW_STATUS_PASSED : MSC_CSW_STATUS_FAILED;
         }
       }
 
diff --git a/tinyusb/tusb_option.h b/tinyusb/tusb_option.h
index 85f828843..755413c2e 100644
--- a/tinyusb/tusb_option.h
+++ b/tinyusb/tusb_option.h
@@ -134,14 +134,6 @@
 #define CFG_TUSB_OS OPT_OS_NONE
 #endif
 
-#if (CFG_TUSB_OS != OPT_OS_NONE) && !defined (CFG_TUD_TASK_PRIO)
-  #error CFG_TUD_TASK_PRIO need to be defined (hint: use the highest if possible)
-#endif
-
-//#ifndef CFG_TUSB_CONFIGURATION_MAX
-//  #define CFG_TUSB_CONFIGURATION_MAX 1
-//  #warning CFG_TUSB_CONFIGURATION_MAX is not defined, default value is 1
-//#endif
 
 #ifndef tu_malloc
 #include <stdlib.h>
@@ -163,11 +155,6 @@
     #define CFG_TUD_ENDOINT0_SIZE    64
   #endif
 
-
-  #if CFG_TUD_ENDOINT0_SIZE > 64
-    #error Control Endpoint Max Package Size cannot larger than 64
-  #endif
-
   #ifndef CFG_TUD_ENUM_BUFFER_SIZE
     #define CFG_TUD_ENUM_BUFFER_SIZE 256
   #endif
@@ -201,6 +188,26 @@
   //------------- CLASS -------------//
 #endif // MODE_HOST_SUPPORTED
 
+
+/*------------------------------------------------------------------*/
+/* Config Verification
+ *------------------------------------------------------------------*/
+
+#if (CFG_TUSB_OS != OPT_OS_NONE) && !defined (CFG_TUD_TASK_PRIO)
+  #error CFG_TUD_TASK_PRIO need to be defined (hint: use the highest if possible)
+#endif
+
+#if CFG_TUD_ENDOINT0_SIZE > 64
+  #error Control Endpoint Max Package Size cannot larger than 64
+#endif
+
+#if CFG_TUD_MSC_MAXLUN == 0 || CFG_TUD_MSC_MAXLUN > 16
+  #error MSC Device: Incorrect setting of MAX LUN
+#endif
+
+//#if CFG_TUD_MSC_BUFSIZE
+
+
 #endif /* _TUSB_OPTION_H_ */
 
 /** @} */