diff --git a/tinyusb/class/cdc/cdc_device.c b/tinyusb/class/cdc/cdc_device.c
index df19cdfc..735a1ff7 100644
--- a/tinyusb/class/cdc/cdc_device.c
+++ b/tinyusb/class/cdc/cdc_device.c
@@ -54,8 +54,8 @@
 CFG_TUSB_ATTR_USBRAM STATIC_VAR cdc_line_coding_t cdcd_line_coding[CONTROLLER_DEVICE_NUMBER];
 
 typedef struct {
-  uint8_t interface_number;
-  cdc_acm_capability_t acm_capability;
+  uint8_t itf_num;
+  cdc_acm_capability_t acm_cap;
 
   // Bit 0:  DTR (Data Terminal Ready), Bit 1: RTS (Request to Send)
   uint8_t line_state;
@@ -63,7 +63,7 @@ typedef struct {
   uint8_t ep_notif;
   uint8_t ep_in;
   uint8_t ep_out;
-}cdcd_data_t;
+}cdcd_interface_t;
 
 // TODO multiple rhport
 #if CFG_TUSB_MCU == OPT_MCU_NRF5X
@@ -81,7 +81,7 @@ FIFO_DEF(_tx_ff, CFG_TUD_CDC_BUFSIZE, uint8_t, false);
 //--------------------------------------------------------------------+
 // INTERNAL OBJECT & FUNCTION DECLARATION
 //--------------------------------------------------------------------+
-STATIC_VAR cdcd_data_t cdcd_data[CONTROLLER_DEVICE_NUMBER];
+STATIC_VAR cdcd_interface_t _cdcd_itf[CONTROLLER_DEVICE_NUMBER];
 
 //--------------------------------------------------------------------+
 // APPLICATION API
@@ -89,12 +89,12 @@ STATIC_VAR cdcd_data_t cdcd_data[CONTROLLER_DEVICE_NUMBER];
 bool tud_n_cdc_connected(uint8_t rhport)
 {
   // DTR (bit 0) active  isconsidered as connected
-  return BIT_TEST_(cdcd_data[rhport].line_state, 0);
+  return BIT_TEST_(_cdcd_itf[rhport].line_state, 0);
 }
 
 uint8_t tud_n_cdc_get_line_state (uint8_t rhport)
 {
-  return cdcd_data[rhport].line_state;
+  return _cdcd_itf[rhport].line_state;
 }
 
 void tud_n_cdc_get_line_coding (uint8_t rhport, cdc_line_coding_t* coding)
@@ -138,7 +138,7 @@ uint32_t tud_n_cdc_write(uint8_t rhport, void const* buffer, uint32_t bufsize)
 
 bool tud_n_cdc_flush (uint8_t rhport)
 {
-  uint8_t  edpt = cdcd_data[rhport].ep_in;
+  uint8_t  edpt = _cdcd_itf[rhport].ep_in;
   VERIFY( !dcd_edpt_busy(rhport, edpt) ); // skip if previous transfer not complete
 
   uint16_t count = fifo_read_n(&_tx_ff, _tmp_tx_buf, sizeof(_tmp_tx_buf));
@@ -156,7 +156,7 @@ bool tud_n_cdc_flush (uint8_t rhport)
 //--------------------------------------------------------------------+
 void cdcd_init(void)
 {
-  memclr_(cdcd_data, sizeof(cdcd_data_t)*CONTROLLER_DEVICE_NUMBER);
+  memclr_(_cdcd_itf, sizeof(cdcd_interface_t)*CONTROLLER_DEVICE_NUMBER);
 
   // default line coding is : stop bit = 1, parity = none, data bits = 8
   memclr_(cdcd_line_coding, sizeof(cdc_line_coding_t)*CONTROLLER_DEVICE_NUMBER);
@@ -180,7 +180,7 @@ tusb_error_t cdcd_open(uint8_t rhport, tusb_desc_interface_t const * p_interface
   }
 
   uint8_t const * p_desc = descriptor_next ( (uint8_t const *) p_interface_desc );
-  cdcd_data_t * p_cdc = &cdcd_data[rhport];
+  cdcd_interface_t * p_cdc = &_cdcd_itf[rhport];
 
   //------------- Communication Interface -------------//
   (*p_length) = sizeof(tusb_desc_interface_t);
@@ -190,7 +190,7 @@ tusb_error_t cdcd_open(uint8_t rhport, tusb_desc_interface_t const * p_interface
   {
     if ( CDC_FUNC_DESC_ABSTRACT_CONTROL_MANAGEMENT == cdc_functional_desc_typeof(p_desc) )
     { // save ACM bmCapabilities
-      p_cdc->acm_capability = ((cdc_desc_func_acm_t const *) p_desc)->bmCapabilities;
+      p_cdc->acm_cap = ((cdc_desc_func_acm_t const *) p_desc)->bmCapabilities;
     }
 
     (*p_length) += p_desc[DESCRIPTOR_OFFSET_LENGTH];
@@ -236,7 +236,7 @@ tusb_error_t cdcd_open(uint8_t rhport, tusb_desc_interface_t const * p_interface
     }
   }
 
-  p_cdc->interface_number   = p_interface_desc->bInterfaceNumber;
+  p_cdc->itf_num   = p_interface_desc->bInterfaceNumber;
 
   // Prepare for incoming data
   TU_ASSERT( dcd_edpt_xfer(rhport, p_cdc->ep_out, _tmp_rx_buf, sizeof(_tmp_rx_buf)), TUSB_ERROR_DCD_EDPT_XFER);
@@ -248,7 +248,7 @@ tusb_error_t cdcd_open(uint8_t rhport, tusb_desc_interface_t const * p_interface
 void cdcd_close(uint8_t rhport)
 {
   // no need to close opened pipe, dcd bus reset will put controller's endpoints to default state
-  memclr_(&cdcd_data[rhport], sizeof(cdcd_data_t));
+  memclr_(&_cdcd_itf[rhport], sizeof(cdcd_interface_t));
 
   fifo_clear(&_rx_ff);
   fifo_clear(&_tx_ff);
@@ -279,7 +279,7 @@ tusb_error_t cdcd_control_request_st(uint8_t rhport, tusb_control_request_t cons
     //        This signal corresponds to V.24 signal 108/2 and RS-232 signal DTR (Data Terminal Ready)
     // Bit 1: Carrier control for half-duplex modems.
     //        This signal corresponds to V.24 signal 105 and RS-232 signal RTS (Request to Send)
-    cdcd_data_t * p_cdc = &cdcd_data[rhport];
+    cdcd_interface_t * p_cdc = &_cdcd_itf[rhport];
 
     p_cdc->line_state = (uint8_t) p_request->wValue;
 
@@ -298,7 +298,7 @@ tusb_error_t cdcd_control_request_st(uint8_t rhport, tusb_control_request_t cons
 
 tusb_error_t cdcd_xfer_cb(uint8_t rhport, uint8_t ep_addr, tusb_event_t event, uint32_t xferred_bytes)
 {
-  cdcd_data_t const * p_cdc = &cdcd_data[rhport];
+  cdcd_interface_t const * p_cdc = &_cdcd_itf[rhport];
 
   if ( ep_addr == p_cdc->ep_out )
   {
diff --git a/tinyusb/class/msc/msc_device.c b/tinyusb/class/msc/msc_device.c
index 9da51a91..c54e64e2 100644
--- a/tinyusb/class/msc/msc_device.c
+++ b/tinyusb/class/msc/msc_device.c
@@ -67,7 +67,7 @@ typedef struct {
 
   CFG_TUSB_MEM_ALIGN msc_csw_t csw;
 
-  uint8_t  interface_num;
+  uint8_t  itf_num;
   uint8_t  ep_in;
   uint8_t  ep_out;
 
@@ -76,7 +76,7 @@ typedef struct {
   uint16_t xferred_len; // numbered of bytes transferred so far in the Data Stage
 }mscd_interface_t;
 
-CFG_TUSB_ATTR_USBRAM CFG_TUSB_MEM_ALIGN STATIC_VAR mscd_interface_t mscd_data;
+CFG_TUSB_ATTR_USBRAM CFG_TUSB_MEM_ALIGN static mscd_interface_t _mscd_itf;
 CFG_TUSB_ATTR_USBRAM CFG_TUSB_MEM_ALIGN static uint8_t _mscd_buf[CFG_TUD_MSC_BUFSIZE];
 
 //--------------------------------------------------------------------+
@@ -89,12 +89,12 @@ static void proc_read10_write10(uint8_t rhport, mscd_interface_t* p_msc);
 //--------------------------------------------------------------------+
 void mscd_init(void)
 {
-  memclr_(&mscd_data, sizeof(mscd_interface_t));
+  memclr_(&_mscd_itf, sizeof(mscd_interface_t));
 }
 
 void mscd_close(uint8_t rhport)
 {
-  memclr_(&mscd_data, sizeof(mscd_interface_t));
+  memclr_(&_mscd_itf, sizeof(mscd_interface_t));
 }
 
 tusb_error_t mscd_open(uint8_t rhport, tusb_desc_interface_t const * p_interface_desc, uint16_t *p_length)
@@ -102,7 +102,7 @@ tusb_error_t mscd_open(uint8_t rhport, tusb_desc_interface_t const * p_interface
   VERIFY( ( MSC_SUBCLASS_SCSI == p_interface_desc->bInterfaceSubClass &&
             MSC_PROTOCOL_BOT  == p_interface_desc->bInterfaceProtocol ), TUSB_ERROR_MSC_UNSUPPORTED_PROTOCOL );
 
-  mscd_interface_t * p_msc = &mscd_data;
+  mscd_interface_t * p_msc = &_mscd_itf;
 
   //------------- Open Data Pipe -------------//
   tusb_desc_endpoint_t const *p_endpoint = (tusb_desc_endpoint_t const *) descriptor_next( (uint8_t const*) p_interface_desc );
@@ -124,7 +124,7 @@ tusb_error_t mscd_open(uint8_t rhport, tusb_desc_interface_t const * p_interface
     p_endpoint = (tusb_desc_endpoint_t const *) descriptor_next( (uint8_t const*)  p_endpoint );
   }
 
-  p_msc->interface_num = p_interface_desc->bInterfaceNumber;
+  p_msc->itf_num = p_interface_desc->bInterfaceNumber;
 
   (*p_length) += sizeof(tusb_desc_interface_t) + 2*sizeof(tusb_desc_endpoint_t);
 
@@ -142,7 +142,7 @@ tusb_error_t mscd_control_request_st(uint8_t rhport, tusb_control_request_t cons
 
   TU_ASSERT(p_request->bmRequestType_bit.type == TUSB_REQ_TYPE_CLASS, TUSB_ERROR_DCD_CONTROL_REQUEST_NOT_SUPPORT);
 
-  mscd_interface_t * p_msc = &mscd_data;
+  mscd_interface_t * p_msc = &_mscd_itf;
 
   if(MSC_REQUEST_RESET == p_request->bRequest)
   {
@@ -163,7 +163,7 @@ tusb_error_t mscd_control_request_st(uint8_t rhport, tusb_control_request_t cons
 
 tusb_error_t mscd_xfer_cb(uint8_t rhport, uint8_t ep_addr, tusb_event_t event, uint32_t xferred_bytes)
 {
-  mscd_interface_t* const p_msc = &mscd_data;
+  mscd_interface_t* const p_msc = &_mscd_itf;
   msc_cbw_t*        const p_cbw = &p_msc->cbw;
   msc_csw_t*        const p_csw = &p_msc->csw;
 
@@ -319,13 +319,10 @@ static void proc_read10_write10(uint8_t rhport, mscd_interface_t* p_msc)
 
   uint32_t xfer_bytes = min32_of(sizeof(_mscd_buf), p_cbw->xfer_bytes-p_msc->xferred_len);
 
+  // Write10 callback will be called later when usb transfer complete
   if (SCSI_CMD_READ_10 == p_cbw->command[0])
   {
     xfer_bytes = tud_msc_read10_cb (rhport, p_cbw->lun, lba, p_msc->xferred_len, _mscd_buf, xfer_bytes);
-  }else
-  {
-    // call later after write transfer complete
-//    xfer_block = tud_msc_write10_cb(rhport, p_cbw->lun, lba, block_count, &p_buffer);
   }
 
   if ( 0 == xfer_bytes  )