diff --git a/examples/device/device_virtual_com/src/main.c b/examples/device/device_virtual_com/src/main.c
index 294f3c2c..b72c0ee2 100644
--- a/examples/device/device_virtual_com/src/main.c
+++ b/examples/device/device_virtual_com/src/main.c
@@ -79,14 +79,14 @@ int main(void)
 void virtual_com_task(void)
 {
   // connected and there are data available
-  if ( tud_mounted(0) && tud_cdc_available(0) )
+  if ( tud_mounted() && tud_cdc_available() )
   {
     uint8_t buf[64];
 
     // read and echo back
-    uint32_t count = tud_cdc_read(0, buf, sizeof(buf));
+    uint32_t count = tud_cdc_read(buf, sizeof(buf));
 
-    tud_cdc_write(0, buf, count);
+    tud_cdc_write(buf, count);
   }
 }
 
diff --git a/tinyusb/class/cdc/cdc_device.c b/tinyusb/class/cdc/cdc_device.c
index 056b9147..557c1ed0 100644
--- a/tinyusb/class/cdc/cdc_device.c
+++ b/tinyusb/class/cdc/cdc_device.c
@@ -76,33 +76,33 @@ STATIC_VAR cdcd_data_t cdcd_data[CONTROLLER_DEVICE_NUMBER];
 //--------------------------------------------------------------------+
 // APPLICATION API
 //--------------------------------------------------------------------+
-bool tud_cdc_connected(uint8_t port)
+bool tud_n_cdc_connected(uint8_t port)
 {
   return cdcd_data[port].connected;
 }
 
-uint32_t tud_cdc_available(uint8_t port)
+uint32_t tud_n_cdc_available(uint8_t port)
 {
   return fifo_count(&_rx_ff);
 }
 
-int tud_cdc_read_char(uint8_t port)
+int tud_n_cdc_read_char(uint8_t port)
 {
   uint8_t ch;
   return fifo_read(&_rx_ff, &ch) ? ch : (-1);
 }
 
-uint32_t tud_cdc_read(uint8_t port, void* buffer, uint32_t bufsize)
+uint32_t tud_n_cdc_read(uint8_t port, void* buffer, uint32_t bufsize)
 {
   return fifo_read_n(&_rx_ff, buffer, bufsize);
 }
 
-uint32_t tud_cdc_write_char(uint8_t port, char ch)
+uint32_t tud_n_cdc_write_char(uint8_t port, char ch)
 {
   return fifo_write(&_tx_ff, &ch);
 }
 
-uint32_t tud_cdc_write(uint8_t port, void const* buffer, uint32_t bufsize)
+uint32_t tud_n_cdc_write(uint8_t port, void const* buffer, uint32_t bufsize)
 {
   return fifo_write_n(&_tx_ff, buffer, bufsize);
 }
@@ -280,7 +280,7 @@ tusb_error_t cdcd_xfer_cb(uint8_t port, uint8_t edpt_addr, tusb_event_t event, u
 
 void cdcd_sof(uint8_t port)
 {
-  if ( !tud_cdc_connected(port) ) return;
+  if ( !tud_n_cdc_connected(port) ) return;
 
   uint8_t edpt = cdcd_data[port].edpt_addr[CDC_PIPE_DATA_IN];
 
diff --git a/tinyusb/class/cdc/cdc_device.h b/tinyusb/class/cdc/cdc_device.h
index db1ef04b..13862a53 100644
--- a/tinyusb/class/cdc/cdc_device.h
+++ b/tinyusb/class/cdc/cdc_device.h
@@ -53,17 +53,49 @@
  *  @{ */
 
 //--------------------------------------------------------------------+
-// APPLICATION API
+// APPLICATION API (Multiple Ports)
 //--------------------------------------------------------------------+
-bool     tud_cdc_connected(uint8_t port);
-uint32_t tud_cdc_available(uint8_t port);
+bool     tud_n_cdc_connected(uint8_t port);
+uint32_t tud_n_cdc_available(uint8_t port);
 
-int      tud_cdc_read_char(uint8_t port);
-uint32_t tud_cdc_read(uint8_t port, void* buffer, uint32_t bufsize);
+int      tud_n_cdc_read_char(uint8_t port);
+uint32_t tud_n_cdc_read(uint8_t port, void* buffer, uint32_t bufsize);
 
-uint32_t tud_cdc_write_char(uint8_t port, char ch);
-uint32_t tud_cdc_write(uint8_t port, void const* buffer, uint32_t bufsize);
+uint32_t tud_n_cdc_write_char(uint8_t port, char ch);
+uint32_t tud_n_cdc_write(uint8_t port, void const* buffer, uint32_t bufsize);
 
+//--------------------------------------------------------------------+
+// APPLICATION API (Single Port)
+//--------------------------------------------------------------------+
+static inline bool     tud_cdc_connected(void)
+{
+  return tud_n_cdc_connected(0);
+}
+
+static inline uint32_t tud_cdc_available(void)
+{
+  return tud_n_cdc_available(0);
+}
+
+static inline int      tud_cdc_read_char(void)
+{
+  return tud_n_cdc_read_char(0);
+}
+
+static inline uint32_t tud_cdc_read(void* buffer, uint32_t bufsize)
+{
+  return tud_n_cdc_read(0, buffer, bufsize);
+}
+
+static inline uint32_t tud_cdc_write_char(char ch)
+{
+  return tud_n_cdc_write_char(0, ch);
+}
+
+static inline uint32_t tud_cdc_write(void const* buffer, uint32_t bufsize)
+{
+  return tud_n_cdc_write(0, buffer, bufsize);
+}
 
 //--------------------------------------------------------------------+
 // APPLICATION CALLBACK API
diff --git a/tinyusb/device/usbd.c b/tinyusb/device/usbd.c
index 2ae86ef8..3220fdac 100644
--- a/tinyusb/device/usbd.c
+++ b/tinyusb/device/usbd.c
@@ -108,9 +108,9 @@ static tusb_error_t get_descriptor(uint8_t port, tusb_control_request_t const *
 //--------------------------------------------------------------------+
 // APPLICATION INTERFACE
 //--------------------------------------------------------------------+
-bool tud_mounted(uint8_t port)
+bool tud_n_mounted(uint8_t port)
 {
-  return usbd_devices[port].state == TUSB_DEVICE_STATE_CONFIGURED;
+    return usbd_devices[port].state == TUSB_DEVICE_STATE_CONFIGURED;
 }
 
 //--------------------------------------------------------------------+
diff --git a/tinyusb/device/usbd.h b/tinyusb/device/usbd.h
index 8258abfd..f16a0215 100644
--- a/tinyusb/device/usbd.h
+++ b/tinyusb/device/usbd.h
@@ -100,7 +100,13 @@ typedef struct {
 //--------------------------------------------------------------------+
 // APPLICATION API
 //--------------------------------------------------------------------+
-bool tud_mounted(uint8_t port);
+bool tud_n_mounted(uint8_t port);
+
+static inline bool tud_mounted(void)
+{
+  return tud_n_mounted(0);
+}
+
 
 /*------------- Callback -------------*/
 /** \brief 			Callback function that will be invoked device is mounted (configured) by USB host
diff --git a/tinyusb/tusb_hal.h b/tinyusb/tusb_hal.h
index dd5d19e0..b36cb29f 100644
--- a/tinyusb/tusb_hal.h
+++ b/tinyusb/tusb_hal.h
@@ -65,22 +65,18 @@ extern "C" {
  *  @{ */
 
 /** \brief    Initialize USB controller hardware
- * \returns   true if succeedded
+ * \returns   true if succeeded
  * \note      This function is invoked by \ref tusb_init as part of the initialization.
  */
 bool tusb_hal_init(void);
 
 /** \brief 			Enable USB Interrupt on a specific USB Controller
  * \param[in]		port	is a zero-based index to identify USB controller's ID
- * \note        Some MCUs such as NXP LPC43xx has multiple USB controllers. It is necessary to know which USB controller for
- *              those MCUs.
  */
 void tusb_hal_init_enable(uint8_t port);
 
 /** \brief 			Disable USB Interrupt on a specific USB Controller
  * \param[in]		port	is a zero-based index to identify USB controller's ID
- * \note        Some MCUs such as NXP LPC43xx has multiple USB controllers. It is necessary to know which USB controller for
- *              those MCUs.
  */
 void tusb_hal_init_disable(uint8_t port);