diff --git a/examples/device/cdc_msc_hid/src/usb_descriptors.c b/examples/device/cdc_msc_hid/src/usb_descriptors.c
index b06658c5..4220dc5f 100644
--- a/examples/device/cdc_msc_hid/src/usb_descriptors.c
+++ b/examples/device/cdc_msc_hid/src/usb_descriptors.c
@@ -124,10 +124,7 @@ enum
   ITF_NUM_TOTAL
 };
 
-enum
-{
-  CONFIG_TOTAL_LEN = TUD_CONFIG_DESC_LEN + CFG_TUD_CDC*TUD_CDC_DESC_LEN + CFG_TUD_MSC*TUD_MSC_DESC_LEN + CFG_TUD_HID*TUD_HID_DESC_LEN
-};
+#define CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + CFG_TUD_CDC*TUD_CDC_DESC_LEN + CFG_TUD_MSC*TUD_MSC_DESC_LEN + CFG_TUD_HID*TUD_HID_DESC_LEN)
 
 #if CFG_TUSB_MCU == OPT_MCU_LPC175X_6X || CFG_TUSB_MCU == OPT_MCU_LPC177X_8X || CFG_TUSB_MCU == OPT_MCU_LPC40XX
   // LPC 17xx and 40xx endpoint type (bulk/interrupt/iso) are fixed by its number
diff --git a/examples/device/cdc_msc_hid_freertos/src/usb_descriptors.c b/examples/device/cdc_msc_hid_freertos/src/usb_descriptors.c
index 65c8cd71..4e1df9fb 100644
--- a/examples/device/cdc_msc_hid_freertos/src/usb_descriptors.c
+++ b/examples/device/cdc_msc_hid_freertos/src/usb_descriptors.c
@@ -124,10 +124,7 @@ enum
   ITF_NUM_TOTAL
 };
 
-enum
-{
-  CONFIG_TOTAL_LEN = TUD_CONFIG_DESC_LEN + CFG_TUD_CDC*TUD_CDC_DESC_LEN + CFG_TUD_MSC*TUD_MSC_DESC_LEN + CFG_TUD_HID*TUD_HID_DESC_LEN
-};
+#define CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + CFG_TUD_CDC*TUD_CDC_DESC_LEN + CFG_TUD_MSC*TUD_MSC_DESC_LEN + CFG_TUD_HID*TUD_HID_DESC_LEN)
 
 #if CFG_TUSB_MCU == OPT_MCU_LPC175X_6X || CFG_TUSB_MCU == OPT_MCU_LPC177X_8X || CFG_TUSB_MCU == OPT_MCU_LPC40XX
   // LPC 17xx and 40xx endpoint type (bulk/interrupt/iso) are fixed by its number
diff --git a/examples/device/hid_generic_inout/src/usb_descriptors.c b/examples/device/hid_generic_inout/src/usb_descriptors.c
index 516dab64..849c2be8 100644
--- a/examples/device/hid_generic_inout/src/usb_descriptors.c
+++ b/examples/device/hid_generic_inout/src/usb_descriptors.c
@@ -92,10 +92,8 @@ enum
   ITF_NUM_TOTAL
 };
 
-enum
-{
-  CONFIG_TOTAL_LEN = TUD_CONFIG_DESC_LEN + TUD_HID_INOUT_DESC_LEN
-};
+
+#define  CONFIG_TOTAL_LEN  (TUD_CONFIG_DESC_LEN + TUD_HID_INOUT_DESC_LEN)
 
 // Use Endpoint 2 instead of 1 due to NXP MCU
 // LPC 17xx and 40xx endpoint type (bulk/interrupt/iso) are fixed by its number
diff --git a/examples/device/midi_test/src/usb_descriptors.c b/examples/device/midi_test/src/usb_descriptors.c
index cffef0fb..85cffffc 100644
--- a/examples/device/midi_test/src/usb_descriptors.c
+++ b/examples/device/midi_test/src/usb_descriptors.c
@@ -77,10 +77,7 @@ enum
   ITF_NUM_TOTAL
 };
 
-enum
-{
-  CONFIG_TOTAL_LEN = TUD_CONFIG_DESC_LEN + TUD_MIDI_DESC_LEN
-};
+#define CONFIG_TOTAL_LEN  (TUD_CONFIG_DESC_LEN + TUD_MIDI_DESC_LEN)
 
 // Use Endpoint 2 instead of 1 due to NXP MCU
 // LPC 17xx and 40xx endpoint type (bulk/interrupt/iso) are fixed by its number
diff --git a/examples/device/msc_dual_lun/src/usb_descriptors.c b/examples/device/msc_dual_lun/src/usb_descriptors.c
index c4e171c0..585588a9 100644
--- a/examples/device/msc_dual_lun/src/usb_descriptors.c
+++ b/examples/device/msc_dual_lun/src/usb_descriptors.c
@@ -75,10 +75,7 @@ enum
   ITF_NUM_TOTAL
 };
 
-enum
-{
-  CONFIG_TOTAL_LEN = TUD_CONFIG_DESC_LEN + TUD_MSC_DESC_LEN
-};
+#define CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + TUD_MSC_DESC_LEN)
 
 // Use Endpoint 2 instead of 1 due to NXP MCU
 // LPC 17xx and 40xx endpoint type (bulk/interrupt/iso) are fixed by its number
diff --git a/examples/device/webusb/src/main.c b/examples/device/webusb/src/main.c
index 6d96eba0..59e93493 100644
--- a/examples/device/webusb/src/main.c
+++ b/examples/device/webusb/src/main.c
@@ -54,7 +54,7 @@ enum  {
 static uint32_t blink_interval_ms = BLINK_NOT_MOUNTED;
 
 void led_blinking_task(void);
-void midi_task(void);
+void cdc_task(void);
 
 /*------------- MAIN -------------*/
 int main(void)
@@ -66,6 +66,7 @@ int main(void)
   while (1)
   {
     tud_task(); // tinyusb device task
+    cdc_task();
     led_blinking_task();
   }
 
@@ -108,6 +109,51 @@ void tud_resume_cb(void)
 //--------------------------------------------------------------------+
 
 
+//--------------------------------------------------------------------+
+// USB CDC
+//--------------------------------------------------------------------+
+void cdc_task(void)
+{
+  if ( tud_cdc_connected() )
+  {
+    // connected and there are data available
+    if ( tud_cdc_available() )
+    {
+      uint8_t buf[64];
+
+      // read and echo back
+      uint32_t count = tud_cdc_read(buf, sizeof(buf));
+
+      for(uint32_t i=0; i<count; i++)
+      {
+        tud_cdc_write_char(buf[i]);
+
+        if ( buf[i] == '\r' ) tud_cdc_write_char('\n');
+      }
+
+      tud_cdc_write_flush();
+    }
+  }
+}
+
+// Invoked when cdc when line state changed e.g connected/disconnected
+void tud_cdc_line_state_cb(uint8_t itf, bool dtr, bool rts)
+{
+  (void) itf;
+
+  // connected
+  if ( dtr && rts )
+  {
+    // print initial message when connected
+    tud_cdc_write_str("\r\nTinyUSB CDC MSC HID device example\r\n");
+  }
+}
+
+// Invoked when CDC interface received data from host
+void tud_cdc_rx_cb(uint8_t itf)
+{
+  (void) itf;
+}
 
 //--------------------------------------------------------------------+
 // BLINKING TASK
diff --git a/examples/device/webusb/src/tusb_config.h b/examples/device/webusb/src/tusb_config.h
index 37a98848..6c126a82 100644
--- a/examples/device/webusb/src/tusb_config.h
+++ b/examples/device/webusb/src/tusb_config.h
@@ -72,12 +72,16 @@
 #define CFG_TUD_ENDOINT0_SIZE       64
 
 //------------- CLASS -------------//
-#define CFG_TUD_CDC                 0
+#define CFG_TUD_CDC                 1
 #define CFG_TUD_MSC                 0
 #define CFG_TUD_HID                 0
 #define CFG_TUD_MIDI                0
 #define CFG_TUD_CUSTOM_CLASS        0
 
+// CDC FIFO size of TX and RX
+#define CFG_TUD_CDC_RX_BUFSIZE      64
+#define CFG_TUD_CDC_TX_BUFSIZE      64
+
 #ifdef __cplusplus
  }
 #endif
diff --git a/examples/device/webusb/src/usb_descriptors.c b/examples/device/webusb/src/usb_descriptors.c
index 188470eb..3ea6f117 100644
--- a/examples/device/webusb/src/usb_descriptors.c
+++ b/examples/device/webusb/src/usb_descriptors.c
@@ -41,7 +41,7 @@ tusb_desc_device_t const desc_device =
 {
     .bLength            = sizeof(tusb_desc_device_t),
     .bDescriptorType    = TUSB_DESC_DEVICE,
-    .bcdUSB             = 0x0210, // at least 2.1 or 3.x
+    .bcdUSB             = 0x0210, // at least 2.1 or 3.x for BOS & webUSB
 
     // Use Interface Association Descriptor (IAD) for CDC
     // As required by USB Specs IAD's subclass must be common class (2) and protocol must be IAD (1)
@@ -72,12 +72,21 @@ uint8_t const * tud_descriptor_device_cb(void)
 // BOS Descriptor
 //--------------------------------------------------------------------+
 
+#define BOS_TOTAL_LEN   (TUD_BOS_DESC_LEN + TUD_BOS_WEBUSB_DESC_LEN)
+
 // BOS Descriptor is required for webUSB
 uint8_t const desc_bos[] =
 {
+  TUD_BOS_DESCRIPTOR(BOS_TOTAL_LEN, 1),
 
+  TUD_BOS_WEBUSB_DESCRIPTOR(0x01, 0)
 };
 
+uint8_t const * tud_descriptor_bos_cb(void)
+{
+  return desc_bos;
+}
+
 //--------------------------------------------------------------------+
 // Configuration Descriptor
 //--------------------------------------------------------------------+
@@ -85,13 +94,11 @@ enum
 {
   ITF_NUM_CDC = 0,
   ITF_NUM_CDC_DATA,
+
   ITF_NUM_TOTAL
 };
 
-enum
-{
-  CONFIG_TOTAL_LEN = TUD_CONFIG_DESC_LEN + TUD_CDC_DESC_LEN
-};
+#define CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + TUD_CDC_DESC_LEN)
 
 // Use Endpoint 2 instead of 1 due to NXP MCU
 // LPC 17xx and 40xx endpoint type (bulk/interrupt/iso) are fixed by its number
diff --git a/src/device/usbd.h b/src/device/usbd.h
index 8bd6adc3..943b1c79 100644
--- a/src/device/usbd.h
+++ b/src/device/usbd.h
@@ -223,10 +223,31 @@ TU_ATTR_WEAK void tud_resume_cb(void);
 
 //------------- WebUSB -------------//
 
-#define TUD_WEBUSB_DESC_LEN
+// Descriptor Length
+#define TUD_BOS_WEBUSB_DESC_LEN   24
+
+// Vendor Code, iLandingPage
+#define TUD_BOS_WEBUSB_DESCRIPTOR(_vendor_code, _ipage) \
+  TUD_BOS_PLATFORM_DESCRIPTOR(TUD_BOS_WEBUSB_UUID, U16_TO_U8S_LE(0x0100), _vendor_code, _ipage)
+
+#define TUD_BOS_WEBUSB_UUID   \
+  0x38, 0xB6, 0x08, 0x34, 0xA9, 0x09, 0xA0, 0x47, \
+  0x8B, 0xFD, 0xA0, 0x76, 0x88, 0x15, 0xB6, 0x65
+
+#if 0
+//------------- Custom -------------//
+
+#define TUD_WEBUSB_DESC_LEN  (9+7+7)
 
 // Interface number, string index, EP Out & IN address, size & polling interval
-#define TUD_WEBUSB_DESCRIPTOR()
+#define TUD_WEBUSB_DESCRIPTOR(_itfnum, _stridx) \
+  /* Interface */\
+  9, TUSB_DESC_INTERFACE, _itfnum, 0, 2, TUSB_CLASS_VENDOR_SPECIFIC, 0x00, 0x00, _stridx,\
+  /* Endpoint Out */\
+  7, TUSB_DESC_ENDPOINT, _epout, TUSB_XFER_BULK, U16_TO_U8S_LE(_epsize), 0,\
+  /* Endpoint In */\
+  7, TUSB_DESC_ENDPOINT, _epin, TUSB_XFER_BULK, U16_TO_U8S_LE(_epsize), 0
+#endif
 
 
 #ifdef __cplusplus