diff --git a/CI/build/conf/cores_config.json b/CI/build/conf/cores_config.json
index c211c47453..0ffa88f468 100644
--- a/CI/build/conf/cores_config.json
+++ b/CI/build/conf/cores_config.json
@@ -97,7 +97,7 @@
             "DISCO_L072CZ_LRWAN1",
             "DISCO_L475VG_IOT"
           ],
-          "options": "usb=HIDFS"
+          "options": "usb=HID"
         },
         {
           "pattern": "X_NUCLEO_IDB05A1_HelloWorld.ino",
diff --git a/boards.txt b/boards.txt
index 7062f7397a..8758114cbd 100644
--- a/boards.txt
+++ b/boards.txt
@@ -2,8 +2,9 @@
 
 menu.pnum=Board part number
 
-menu.xserial=Serial interface
-menu.usb=USB interface (if available)
+menu.xserial=U(S)ART support
+menu.usb=USB support (if available)
+menu.xusb=USB speed (if available)
 
 menu.opt=Optimize
 menu.rtlib=C Runtime Library
@@ -578,7 +579,7 @@ GenF1.menu.pnum.MAPLEMINI_F103CB.build.product_line=STM32F103xB
 GenF1.menu.pnum.MAPLEMINI_F103CB.build.variant=MAPLEMINI_F103CB
 
 # HY-TinySTM103TB board
-# Support: 
+# Support:
 GenF1.menu.pnum.HY_TinySTM103TB=HY-TinySTM103TB
 GenF1.menu.pnum.HY_TinySTM103TB.upload.maximum_size=131072
 GenF1.menu.pnum.HY_TinySTM103TB.upload.maximum_data_size=20480
@@ -841,128 +842,149 @@ RAK.menu.upload_method.STLink.upload.tool=stlink_upload
 
 ################################################################################
 # Serialx activation
-Nucleo_144.menu.xserial.generic=Enabled with generic Serial
-Nucleo_144.menu.xserial.none=Enabled without generic Serial
+Nucleo_144.menu.xserial.generic=Enabled (generic 'Serial')
+Nucleo_144.menu.xserial.none=Enabled (no generic 'Serial')
 Nucleo_144.menu.xserial.none.build.xSerial=-DHAL_UART_MODULE_ENABLED -DHWSERIAL_NONE
-Nucleo_144.menu.xserial.disabled=Disabled (No Serial)
+Nucleo_144.menu.xserial.disabled=Disabled (No Serial support)
 Nucleo_144.menu.xserial.disabled.build.xSerial=
 
-Nucleo_64.menu.xserial.generic=Enabled with generic Serial
-Nucleo_64.menu.xserial.none=Enabled without generic Serial
+Nucleo_64.menu.xserial.generic=Enabled (generic 'Serial')
+Nucleo_64.menu.xserial.none=Enabled (no generic 'Serial')
 Nucleo_64.menu.xserial.none.build.xSerial=-DHAL_UART_MODULE_ENABLED -DHWSERIAL_NONE
-Nucleo_64.menu.xserial.disabled=Disabled (No Serial)
+Nucleo_64.menu.xserial.disabled=Disabled (No Serial support)
 Nucleo_64.menu.xserial.disabled.build.xSerial=
 
-Nucleo_32.menu.xserial.generic=Enabled with generic Serial
-Nucleo_32.menu.xserial.none=Enabled without generic Serial
+Nucleo_32.menu.xserial.generic=Enabled (generic 'Serial')
+Nucleo_32.menu.xserial.none=Enabled (no generic 'Serial')
 Nucleo_32.menu.xserial.none.build.xSerial=-DHAL_UART_MODULE_ENABLED -DHWSERIAL_NONE
-Nucleo_32.menu.xserial.disabled=Disabled (No Serial)
+Nucleo_32.menu.xserial.disabled=Disabled (No Serial support)
 Nucleo_32.menu.xserial.disabled.build.xSerial=
 
-Disco.menu.xserial.generic=Enabled with generic Serial
-Disco.menu.xserial.none=Enabled without generic Serial
+Disco.menu.xserial.generic=Enabled (generic 'Serial')
+Disco.menu.xserial.none=Enabled (no generic 'Serial')
 Disco.menu.xserial.none.build.xSerial=-DHAL_UART_MODULE_ENABLED -DHWSERIAL_NONE
-Disco.menu.xserial.disabled=Disabled (No Serial)
+Disco.menu.xserial.disabled=Disabled (no Serial support)
 Disco.menu.xserial.disabled.build.xSerial=
 
-GenF0.menu.xserial.generic=Enabled with generic Serial
-GenF0.menu.xserial.none=Enabled without generic Serial
+GenF0.menu.xserial.generic=Enabled (generic 'Serial')
+GenF0.menu.xserial.none=Enabled (no generic 'Serial')
 GenF0.menu.xserial.none.build.xSerial=-DHAL_UART_MODULE_ENABLED -DHWSERIAL_NONE
-GenF0.menu.xserial.disabled=Disabled (No Serial)
+GenF0.menu.xserial.disabled=Disabled (no Serial support)
 GenF0.menu.xserial.disabled.build.xSerial=
 
-GenF1.menu.xserial.generic=Enabled with generic Serial
-GenF1.menu.xserial.none=Enabled without generic Serial
+GenF1.menu.xserial.generic=Enabled (generic 'Serial')
+GenF1.menu.xserial.none=Enabled (no generic 'Serial')
 GenF1.menu.xserial.none.build.xSerial=-DHAL_UART_MODULE_ENABLED -DHWSERIAL_NONE
-GenF1.menu.xserial.disabled=Disabled (No Serial)
+GenF1.menu.xserial.disabled=Disabled (no Serial support)
 GenF1.menu.xserial.disabled.build.xSerial=
 
-GenF4.menu.xserial.generic=Enabled with generic Serial
-GenF4.menu.xserial.none=Enabled without generic Serial
+GenF4.menu.xserial.generic=Enabled (generic 'Serial')
+GenF4.menu.xserial.none=Enabled (no generic 'Serial')
 GenF4.menu.xserial.none.build.xSerial=-DHAL_UART_MODULE_ENABLED -DHWSERIAL_NONE
-GenF4.menu.xserial.disabled=Disabled (No Serial)
+GenF4.menu.xserial.disabled=Disabled (no Serial support)
 GenF4.menu.xserial.disabled.build.xSerial=
 
-RAK.menu.xserial.generic=Enabled with generic Serial
-RAK.menu.xserial.none=Enabled without generic Serial
+RAK.menu.xserial.generic=Enabled (generic 'Serial')
+RAK.menu.xserial.none=Enabled (no generic 'Serial')
 RAK.menu.xserial.none.build.xSerial=-DHAL_UART_MODULE_ENABLED -DHWSERIAL_NONE
-RAK.menu.xserial.disabled=Disabled (No Serial)
+RAK.menu.xserial.disabled=Disabled (no Serial support)
 RAK.menu.xserial.disabled.build.xSerial=
 
-3dprinter.menu.xserial.generic=Enabled with generic Serial
-3dprinter.menu.xserial.none=Enabled without generic Serial
+3dprinter.menu.xserial.generic=Enabled (generic 'Serial')
+3dprinter.menu.xserial.none=Enabled (no generic 'Serial')
 3dprinter.menu.xserial.none.build.xSerial=-DHAL_UART_MODULE_ENABLED -DHWSERIAL_NONE
-3dprinter.menu.xserial.disabled=Disabled (No Serial)
+3dprinter.menu.xserial.disabled=Disabled (no Serial support)
 3dprinter.menu.xserial.disabled.build.xSerial=
 
 # USB connectivity
 Nucleo_144.menu.usb.none=None
-Nucleo_144.menu.usb.none=None
-Nucleo_144.menu.usb.HIDFS=HID keyboard and mouse support Full Speed
-Nucleo_144.menu.usb.HIDFS.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE
-Nucleo_144.menu.usb.HIDHS=HID keyboard and mouse support High Speed
-Nucleo_144.menu.usb.HIDHS.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE -DUSE_USB_HS
-Nucleo_144.menu.usb.CDCFS=CDC Full Speed
-Nucleo_144.menu.usb.CDCFS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
-Nucleo_144.menu.usb.CDCHS=CDC High Speed
-Nucleo_144.menu.usb.CDCHS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DUSE_USB_HS
+Nucleo_144.menu.usb.CDCgen=CDC (generic 'Serial' supersede U(S)ART)
+Nucleo_144.menu.usb.CDCgen.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
+Nucleo_144.menu.usb.CDC=CDC (no generic 'Serial')
+Nucleo_144.menu.usb.CDC.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DDISABLE_GENERIC_SERIALUSB
+Nucleo_144.menu.usb.HID=HID (keyboard and mouse)
+Nucleo_144.menu.usb.HID.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE
+Nucleo_144.menu.xusb.FS=Low/Full Speed
+Nucleo_144.menu.xusb.HS=High Speed
+Nucleo_144.menu.xusb.HS.build.usb_speed=-DUSE_USB_HS
+Nucleo_144.menu.xusb.HSFS=High Speed in Full Speed mode
+Nucleo_144.menu.xusb.HSFS.build.usb_speed=-DUSE_USB_HS -DUSE_USB_HS_IN_FS
 
 Nucleo_64.menu.usb.none=None
-Nucleo_64.menu.usb.none=None
-Nucleo_64.menu.usb.HIDFS=HID keyboard and mouse support Full Speed
-Nucleo_64.menu.usb.HIDFS.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE
-Nucleo_64.menu.usb.HIDHS=HID keyboard and mouse support High Speed
-Nucleo_64.menu.usb.HIDHS.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE -DUSE_USB_HS
-Nucleo_64.menu.usb.CDCFS=CDC Full Speed
-Nucleo_64.menu.usb.CDCFS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
-Nucleo_64.menu.usb.CDCHS=CDC High Speed
-Nucleo_64.menu.usb.CDCHS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DUSE_USB_HS
+Nucleo_64.menu.usb.CDCgen=CDC (generic 'Serial' supersede U(S)ART)
+Nucleo_64.menu.usb.CDCgen.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
+Nucleo_64.menu.usb.CDC=CDC (no generic 'Serial')
+Nucleo_64.menu.usb.CDC.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DDISABLE_GENERIC_SERIALUSB
+Nucleo_64.menu.usb.HID=HID (keyboard and mouse)
+Nucleo_64.menu.usb.HID.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE
+Nucleo_64.menu.xusb.FS=Low/Full Speed
+Nucleo_64.menu.xusb.HS=High Speed
+Nucleo_64.menu.xusb.HS.build.usb_speed=-DUSE_USB_HS
+Nucleo_64.menu.xusb.HSFS=High Speed in Full Speed mode
+Nucleo_64.menu.xusb.HSFS.build.usb_speed=-DUSE_USB_HS -DUSE_USB_HS_IN_FS
 
 Nucleo_32.menu.usb.none=None
-Nucleo_32.menu.usb.HIDFS=HID keyboard and mouse support Full Speed
-Nucleo_32.menu.usb.HIDFS.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE
-Nucleo_32.menu.usb.HIDHS=HID keyboard and mouse support High Speed
-Nucleo_32.menu.usb.HIDHS.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE -DUSE_USB_HS
-Nucleo_32.menu.usb.CDCFS=CDC Full Speed
-Nucleo_32.menu.usb.CDCFS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
-Nucleo_32.menu.usb.CDCHS=CDC High Speed
-Nucleo_32.menu.usb.CDCHS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DUSE_USB_HS
+Nucleo_32.menu.usb.CDCgen=CDC (generic 'Serial' supersede U(S)ART)
+Nucleo_32.menu.usb.CDCgen.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
+Nucleo_32.menu.usb.CDC=CDC (no generic 'Serial')
+Nucleo_32.menu.usb.CDC.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DDISABLE_GENERIC_SERIALUSB
+Nucleo_32.menu.usb.HID=HID (keyboard and mouse)
+Nucleo_32.menu.usb.HID.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE
+Nucleo_32.menu.xusb.FS=Low/Full Speed
+Nucleo_32.menu.xusb.HS=High Speed
+Nucleo_32.menu.xusb.HS.build.usb_speed=-DUSE_USB_HS
+Nucleo_32.menu.xusb.HSFS=High Speed in Full Speed mode
+Nucleo_32.menu.xusb.HSFS.build.usb_speed=-DUSE_USB_HS -DUSE_USB_HS_IN_FS
 
 Disco.menu.usb.none=None
-Disco.menu.usb.HIDFS=HID keyboard and mouse support Full Speed
-Disco.menu.usb.HIDFS.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE
-Disco.menu.usb.HIDHS=HID keyboard and mouse support High Speed
-Disco.menu.usb.HIDHS.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE -DUSE_USB_HS
-Disco.menu.usb.CDCFS=CDC Full Speed
-Disco.menu.usb.CDCFS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
-Disco.menu.usb.CDCHS=CDC High Speed
-Disco.menu.usb.CDCHS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DUSE_USB_HS
+Disco.menu.usb.CDCgen=CDC (generic 'Serial' supersede U(S)ART)
+Disco.menu.usb.CDCgen.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
+Disco.menu.usb.CDC=CDC (no generic 'Serial')
+Disco.menu.usb.CDC.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DDISABLE_GENERIC_SERIALUSB
+Disco.menu.usb.HID=HID (keyboard and mouse)
+Disco.menu.usb.HID.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE
+Disco.menu.xusb.FS=Low/Full Speed
+Disco.menu.xusb.HS=High Speed
+Disco.menu.xusb.HS.build.usb_speed=-DUSE_USB_HS
+Disco.menu.xusb.HSFS=High Speed in Full Speed mode
+Disco.menu.xusb.HSFS.build.usb_speed=-DUSE_USB_HS -DUSE_USB_HS_IN_FS
 
 GenF1.menu.usb.none=None
-GenF1.menu.usb.HIDFS=HID keyboard and mouse support Full Speed
-GenF1.menu.usb.HIDFS.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE
-GenF1.menu.usb.HIDHS=HID keyboard and mouse support High Speed
-GenF1.menu.usb.HIDHS.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE -DUSE_USB_HS
-GenF1.menu.usb.CDCFS=CDC Full Speed
-GenF1.menu.usb.CDCFS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
-GenF1.menu.usb.CDCHS=CDC High Speed
-GenF1.menu.usb.CDCHS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DUSE_USB_HS
+GenF1.menu.usb.CDCgen=CDC (generic 'Serial' supersede U(S)ART)
+GenF1.menu.usb.CDCgen.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
+GenF1.menu.usb.CDC=CDC (no generic 'Serial')
+GenF1.menu.usb.CDC.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DDISABLE_GENERIC_SERIALUSB
+GenF1.menu.usb.HID=HID (keyboard and mouse)
+GenF1.menu.usb.HID.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE
+GenF1.menu.xusb.FS=Low/Full Speed
+GenF1.menu.xusb.HS=High Speed
+GenF1.menu.xusb.HS.build.usb_speed=-DUSE_USB_HS
+GenF1.menu.xusb.HSFS=High Speed in Full Speed mode
+GenF1.menu.xusb.HSFS.build.usb_speed=-DUSE_USB_HS -DUSE_USB_HS_IN_FS
 
 GenF4.menu.usb.none=None
-GenF4.menu.usb.HIDFS=HID keyboard and mouse support Full Speed
-GenF4.menu.usb.HIDFS.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE
-GenF4.menu.usb.HIDHS=HID keyboard and mouse support High Speed
-GenF4.menu.usb.HIDHS.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE -DUSE_USB_HS
-GenF4.menu.usb.CDCFS=CDC Full Speed
-GenF4.menu.usb.CDCFS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
-GenF4.menu.usb.CDCHS=CDC High Speed
-GenF4.menu.usb.CDCHS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DUSE_USB_HS
+GenF4.menu.usb.CDCgen=CDC (generic 'Serial' supersede U(S)ART)
+GenF4.menu.usb.CDCgen.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
+GenF4.menu.usb.CDC=CDC (no generic 'Serial')
+GenF4.menu.usb.CDC.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DDISABLE_GENERIC_SERIALUSB
+GenF4.menu.usb.HID=HID (keyboard and mouse)
+GenF4.menu.usb.HID.build.enable_usb={build.usb_flags} -DUSBD_USE_HID_COMPOSITE
+GenF4.menu.xusb.FS=Low/Full Speed
+GenF4.menu.xusb.HS=High Speed
+GenF4.menu.xusb.HS.build.usb_speed=-DUSE_USB_HS
+GenF4.menu.xusb.HSFS=High Speed in Full Speed mode
+GenF4.menu.xusb.HSFS.build.usb_speed=-DUSE_USB_HS -DUSE_USB_HS_IN_FS
 
 3dprinter.menu.usb.none=None
-3dprinter.menu.usb.CDCFS=CDC Full Speed
-3dprinter.menu.usb.CDCFS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
-3dprinter.menu.usb.CDCHS=CDC High Speed
-3dprinter.menu.usb.CDCHS.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DUSE_USB_HS
+3dprinter.menu.usb.CDCgen=CDC (generic 'Serial' supersede U(S)ART)
+3dprinter.menu.usb.CDCgen.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC
+3dprinter.menu.usb.CDC=CDC (no generic 'Serial')
+3dprinter.menu.usb.CDC.build.enable_usb={build.usb_flags} -DUSBD_USE_CDC -DDISABLE_GENERIC_SERIALUSB
+3dprinter.menu.xusb.FS=Low/Full Speed
+3dprinter.menu.xusb.HS=High Speed
+3dprinter.menu.xusb.HS.build.usb_speed=-DUSE_USB_HS
+3dprinter.menu.xusb.HSFS=High Speed in Full Speed mode
+3dprinter.menu.xusb.HSFS.build.usb_speed=-DUSE_USB_HS -DUSE_USB_HS_IN_FS
 
 # Optimizations
 Nucleo_144.menu.opt.osstd=Smallest (-Os default)
diff --git a/cores/arduino/HardwareSerial.cpp b/cores/arduino/HardwareSerial.cpp
index b606e41fd6..1471f935b9 100644
--- a/cores/arduino/HardwareSerial.cpp
+++ b/cores/arduino/HardwareSerial.cpp
@@ -105,43 +105,6 @@
 #endif
 #endif // HAVE_HWSERIALx
 
-void serialEventRun(void)
-{
-#if defined(HAVE_HWSERIAL1)
-  if (serialEvent1 && Serial1.available()) serialEvent1();
-#endif
-#if defined(HAVE_HWSERIAL2)
-  if (serialEvent2 && Serial2.available()) serialEvent2();
-#endif
-#if defined(HAVE_HWSERIAL3)
-  if (serialEvent3 && Serial3.available()) serialEvent3();
-#endif
-#if defined(HAVE_HWSERIAL4)
-  if (serialEvent4 && Serial4.available()) serialEvent4();
-#endif
-#if defined(HAVE_HWSERIAL5)
-  if (serialEvent5 && Serial5.available()) serialEvent5();
-#endif
-#if defined(HAVE_HWSERIAL6)
-  if (serialEvent6 && Serial6.available()) serialEvent6();
-#endif
-#if defined(HAVE_HWSERIAL7)
-  if (serialEvent7 && Serial7.available()) serialEvent7();
-#endif
-#if defined(HAVE_HWSERIAL8)
-  if (serialEvent8 && Serial8.available()) serialEvent8();
-#endif
-#if defined(HAVE_HWSERIAL9)
-  if (serialEvent9 && Serial9.available()) serialEvent9();
-#endif
-#if defined(HAVE_HWSERIAL10)
-  if (serialEventl10 && Serial10.available()) serialEvent10();
-#endif
-#if defined(HAVE_HWSERIALLP1)
-  if (serialEventLP1 && SerialLP1.available()) serialEventLP1();
-#endif
-}
-
 // Constructors ////////////////////////////////////////////////////////////////
 HardwareSerial::HardwareSerial(uint32_t _rx, uint32_t _tx)
 {
diff --git a/cores/arduino/HardwareSerial.h b/cores/arduino/HardwareSerial.h
index 1484d67401..9740a2f291 100644
--- a/cores/arduino/HardwareSerial.h
+++ b/cores/arduino/HardwareSerial.h
@@ -27,6 +27,7 @@
 #include <inttypes.h>
 
 #include "Stream.h"
+#include "uart.h"
 
 // Define constants and variables for buffering incoming serial data.  We're
 // using a ring buffer (I think), in which head is the index of the location
@@ -148,6 +149,4 @@ extern HardwareSerial Serial9;
 extern HardwareSerial Serial10;
 extern HardwareSerial SerialLP1;
 
-extern void serialEventRun(void) __attribute__((weak));
-
 #endif
diff --git a/cores/arduino/USBSerial.cpp b/cores/arduino/USBSerial.cpp
index b11d4f5c8d..7df1d48e42 100644
--- a/cores/arduino/USBSerial.cpp
+++ b/cores/arduino/USBSerial.cpp
@@ -37,6 +37,7 @@ extern __IO uint32_t UserRxBufPtrIn;
 extern __IO uint32_t UserRxBufPtrOut;
 
 USBSerial SerialUSB;
+void serialEventUSB() __attribute__((weak));
 
 void USBSerial::begin(uint32_t /* baud_count */) {
   // uart config is ignored in USB-CDC
diff --git a/cores/arduino/WSerial.cpp b/cores/arduino/WSerial.cpp
new file mode 100644
index 0000000000..0620924df0
--- /dev/null
+++ b/cores/arduino/WSerial.cpp
@@ -0,0 +1,42 @@
+#include "WSerial.h"
+
+void serialEventRun(void)
+{
+#if defined(HAVE_HWSERIAL1)
+  if (serialEvent1 && Serial1.available()) serialEvent1();
+#endif
+#if defined(HAVE_HWSERIAL2)
+  if (serialEvent2 && Serial2.available()) serialEvent2();
+#endif
+#if defined(HAVE_HWSERIAL3)
+  if (serialEvent3 && Serial3.available()) serialEvent3();
+#endif
+#if defined(HAVE_HWSERIAL4)
+  if (serialEvent4 && Serial4.available()) serialEvent4();
+#endif
+#if defined(HAVE_HWSERIAL5)
+  if (serialEvent5 && Serial5.available()) serialEvent5();
+#endif
+#if defined(HAVE_HWSERIAL6)
+  if (serialEvent6 && Serial6.available()) serialEvent6();
+#endif
+#if defined(HAVE_HWSERIAL7)
+  if (serialEvent7 && Serial7.available()) serialEvent7();
+#endif
+#if defined(HAVE_HWSERIAL8)
+  if (serialEvent8 && Serial8.available()) serialEvent8();
+#endif
+#if defined(HAVE_HWSERIAL9)
+  if (serialEvent9 && Serial9.available()) serialEvent9();
+#endif
+#if defined(HAVE_HWSERIAL10)
+  if (serialEventl10 && Serial10.available()) serialEvent10();
+#endif
+#if defined(HAVE_HWSERIALLP1)
+  if (serialEventLP1 && SerialLP1.available()) serialEventLP1();
+#endif
+#if defined(HAVE_SERIALUSB)
+  if (serialEventUSB && SerialUSB.available()) serialEventUSB();
+#endif
+}
+
diff --git a/cores/arduino/WSerial.h b/cores/arduino/WSerial.h
new file mode 100644
index 0000000000..a55697b455
--- /dev/null
+++ b/cores/arduino/WSerial.h
@@ -0,0 +1,170 @@
+#ifndef WIRING_SERIAL_H
+#define WIRING_SERIAL_H
+
+#include "variant.h"
+#include "HardwareSerial.h"
+#include "USBSerial.h"
+
+#if defined (USBCON) && defined(USBD_USE_CDC)
+#ifndef DISABLE_GENERIC_SERIALUSB
+#define ENABLE_SERIALUSB
+#if !defined(Serial)
+#define Serial SerialUSB
+#define serialEvent serialEventUSB
+#endif
+#endif
+
+#if defined(ENABLE_SERIALUSB)
+#define HAVE_SERIALUSB
+#endif
+
+extern void serialEventUSB(void) __attribute__((weak));
+#endif /* USBCON && USBD_USE_CDC */
+
+#if defined(HAL_UART_MODULE_ENABLED)
+#if !defined(HWSERIAL_NONE) && defined(SERIAL_UART_INSTANCE)
+#if SERIAL_UART_INSTANCE == 0
+#define ENABLE_HWSERIALLP1
+#if !defined(Serial)
+#define Serial SerialLP1
+#define serialEvent serialEventLP1
+#endif
+#elif SERIAL_UART_INSTANCE == 1
+#define ENABLE_HWSERIAL1
+#if !defined(Serial)
+#define Serial Serial1
+#define serialEvent serialEvent1
+#endif
+#elif SERIAL_UART_INSTANCE == 2
+#define ENABLE_HWSERIAL2
+#if !defined(Serial)
+#define Serial Serial2
+#define serialEvent serialEvent2
+#endif
+#elif SERIAL_UART_INSTANCE == 3
+#define ENABLE_HWSERIAL3
+#if !defined(Serial)
+#define Serial Serial3
+#define serialEvent serialEvent3
+#endif
+#elif SERIAL_UART_INSTANCE == 4
+#define ENABLE_HWSERIAL4
+#if !defined(Serial)
+#define Serial Serial4
+#define serialEvent serialEvent4
+#endif
+#elif SERIAL_UART_INSTANCE == 5
+#define ENABLE_HWSERIAL5
+#if !defined(Serial)
+#define Serial Serial5
+#define serialEvent serialEvent5
+#endif
+#elif SERIAL_UART_INSTANCE == 6
+#define ENABLE_HWSERIAL6
+#if !defined(Serial)
+#define Serial Serial6
+#define serialEvent serialEvent6
+#endif
+#elif SERIAL_UART_INSTANCE == 7
+#define ENABLE_HWSERIAL7
+#if !defined(Serial)
+#define Serial Serial7
+#define serialEvent serialEvent7
+#endif
+#elif SERIAL_UART_INSTANCE == 8
+#define ENABLE_HWSERIAL8
+#if !defined(Serial)
+#define Serial Serial8
+#define serialEvent serialEvent8
+#endif
+#elif SERIAL_UART_INSTANCE == 9
+#define ENABLE_HWSERIAL9
+#if !defined(Serial)
+#define Serial Serial9
+#define serialEvent serialEvent9
+#endif
+#elif SERIAL_UART_INSTANCE == 10
+#define ENABLE_HWSERIAL10
+#if !defined(Serial)
+#define Serial Serial10
+#define serialEvent serialEvent10
+#endif
+#else
+#if !defined(Serial)
+#warning "No generic 'Serial' defined!"
+#endif
+#endif /* SERIAL_UART_INSTANCE == x */
+#endif /* !HWSERIAL_NONE && SERIAL_UART_INSTANCE */
+
+#if defined(ENABLE_HWSERIALLP1)
+#if defined(LPUART1_BASE)
+#define HAVE_HWSERIALLP1
+#endif
+#endif
+#if defined(ENABLE_HWSERIAL1)
+#if defined(USART1_BASE)
+#define HAVE_HWSERIAL1
+#endif
+#endif
+#if defined(ENABLE_HWSERIAL2)
+#if defined(USART2_BASE)
+#define HAVE_HWSERIAL2
+#endif
+#endif
+#if defined(ENABLE_HWSERIAL3)
+#if defined(USART3_BASE)
+#define HAVE_HWSERIAL3
+#endif
+#endif
+#if defined(ENABLE_HWSERIAL4)
+#if defined(USART4_BASE) || defined(UART4_BASE)
+#define HAVE_HWSERIAL4
+#endif
+#endif
+#if defined(ENABLE_HWSERIAL5)
+#if defined(USART5_BASE) || defined(UART5_BASE)
+#define HAVE_HWSERIAL5
+#endif
+#endif
+#if defined(ENABLE_HWSERIAL6)
+#if defined(USART6_BASE)
+#define HAVE_HWSERIAL6
+#endif
+#endif
+#if defined(ENABLE_HWSERIAL7)
+#if defined(USART7_BASE) || defined(UART7_BASE)
+#define HAVE_HWSERIAL7
+#endif
+#endif
+#if defined(ENABLE_HWSERIAL8)
+#if defined(USART8_BASE) || defined(UART8_BASE)
+#define HAVE_HWSERIAL8
+#endif
+#endif
+#if defined(ENABLE_HWSERIAL9)
+#if defined(UART9_BASE)
+#define HAVE_HWSERIAL9
+#endif
+#endif
+#if defined(ENABLE_HWSERIAL10)
+#if defined(UART10_BASE)
+#define HAVE_HWSERIAL10
+#endif
+#endif
+
+extern void serialEvent1(void) __attribute__((weak));
+extern void serialEvent2(void) __attribute__((weak));
+extern void serialEvent3(void) __attribute__((weak));
+extern void serialEvent4(void) __attribute__((weak));
+extern void serialEvent5(void) __attribute__((weak));
+extern void serialEvent6(void) __attribute__((weak));
+extern void serialEvent7(void) __attribute__((weak));
+extern void serialEvent8(void) __attribute__((weak));
+extern void serialEvent9(void) __attribute__((weak));
+extern void serialEvent10(void) __attribute__((weak));
+extern void serialEventLP1(void) __attribute__((weak));
+#endif /* HAL_UART_MODULE_ENABLED */
+
+extern void serialEventRun(void) __attribute__((weak));
+
+#endif /* WIRING_SERIAL_H */
diff --git a/cores/arduino/stm32/uart.h b/cores/arduino/stm32/uart.h
index 4f315eaf6a..02d1a9b3f2 100644
--- a/cores/arduino/stm32/uart.h
+++ b/cores/arduino/stm32/uart.h
@@ -48,136 +48,6 @@
 #if !defined(HAL_UART_MODULE_ENABLED)
 #define serial_t void*
 #else
-#if !defined(HWSERIAL_NONE) && defined(SERIAL_UART_INSTANCE)
-
-#if SERIAL_UART_INSTANCE == 0
-#define ENABLE_HWSERIALLP1
-#if !defined(Serial)
-#define Serial SerialLP1
-#define serialEvent serialEventLP1
-#endif
-#elif SERIAL_UART_INSTANCE == 1
-#define ENABLE_HWSERIAL1
-#if !defined(Serial)
-#define Serial Serial1
-#define serialEvent serialEvent1
-#endif
-#elif SERIAL_UART_INSTANCE == 2
-#define ENABLE_HWSERIAL2
-#if !defined(Serial)
-#define Serial Serial2
-#define serialEvent serialEvent2
-#endif
-#elif SERIAL_UART_INSTANCE == 3
-#define ENABLE_HWSERIAL3
-#if !defined(Serial)
-#define Serial Serial3
-#define serialEvent serialEvent3
-#endif
-#elif SERIAL_UART_INSTANCE == 4
-#define ENABLE_HWSERIAL4
-#if !defined(Serial)
-#define Serial Serial4
-#define serialEvent serialEvent4
-#endif
-#elif SERIAL_UART_INSTANCE == 5
-#define ENABLE_HWSERIAL5
-#if !defined(Serial)
-#define Serial Serial5
-#define serialEvent serialEvent5
-#endif
-#elif SERIAL_UART_INSTANCE == 6
-#define ENABLE_HWSERIAL6
-#if !defined(Serial)
-#define Serial Serial6
-#define serialEvent serialEvent6
-#endif
-#elif SERIAL_UART_INSTANCE == 7
-#define ENABLE_HWSERIAL7
-#if !defined(Serial)
-#define Serial Serial7
-#define serialEvent serialEvent7
-#endif
-#elif SERIAL_UART_INSTANCE == 8
-#define ENABLE_HWSERIAL8
-#if !defined(Serial)
-#define Serial Serial8
-#define serialEvent serialEvent8
-#endif
-#elif SERIAL_UART_INSTANCE == 9
-#define ENABLE_HWSERIAL9
-#if !defined(Serial)
-#define Serial Serial9
-#define serialEvent serialEvent9
-#endif
-#elif SERIAL_UART_INSTANCE == 10
-#define ENABLE_HWSERIAL10
-#if !defined(Serial)
-#define Serial Serial10
-#define serialEvent serialEvent10
-#endif
-#else
-#if !defined(Serial)
-#warning "No generic 'Serial' defined!"
-#endif
-#endif /* SERIAL_UART_INSTANCE == x */
-#endif /* !HWSERIAL_NONE && SERIAL_UART_INSTANCE */
-
-#if defined(ENABLE_HWSERIALLP1)
-#if defined(LPUART1_BASE)
-#define HAVE_HWSERIALLP1
-#endif
-#endif
-#if defined(ENABLE_HWSERIAL1)
-#if defined(USART1_BASE)
-#define HAVE_HWSERIAL1
-#endif
-#endif
-#if defined(ENABLE_HWSERIAL2)
-#if defined(USART2_BASE)
-#define HAVE_HWSERIAL2
-#endif
-#endif
-#if defined(ENABLE_HWSERIAL3)
-#if defined(USART3_BASE)
-#define HAVE_HWSERIAL3
-#endif
-#endif
-#if defined(ENABLE_HWSERIAL4)
-#if defined(USART4_BASE) || defined(UART4_BASE)
-#define HAVE_HWSERIAL4
-#endif
-#endif
-#if defined(ENABLE_HWSERIAL5)
-#if defined(USART5_BASE) || defined(UART5_BASE)
-#define HAVE_HWSERIAL5
-#endif
-#endif
-#if defined(ENABLE_HWSERIAL6)
-#if defined(USART6_BASE)
-#define HAVE_HWSERIAL6
-#endif
-#endif
-#if defined(ENABLE_HWSERIAL7)
-#if defined(USART7_BASE) || defined(UART7_BASE)
-#define HAVE_HWSERIAL7
-#endif
-#endif
-#if defined(ENABLE_HWSERIAL8)
-#if defined(USART8_BASE) || defined(UART8_BASE)
-#define HAVE_HWSERIAL8
-#endif
-#endif
-#if defined(ENABLE_HWSERIAL9)
-#if defined(UART9_BASE)
-#define HAVE_HWSERIAL9
-#endif
-#endif
-#if defined(ENABLE_HWSERIAL10)
-#if defined(UART10_BASE)
-#define HAVE_HWSERIAL10
-#endif
-#endif
 
 /* Exported types ------------------------------------------------------------*/
 typedef struct serial_s serial_t;
diff --git a/cores/arduino/wiring.h b/cores/arduino/wiring.h
index b2d0efc741..081a82c7bf 100644
--- a/cores/arduino/wiring.h
+++ b/cores/arduino/wiring.h
@@ -41,14 +41,14 @@
 #include <board.h>
 
 #ifdef __cplusplus
-#include "HardwareSerial.h"
 #include "Tone.h"
-#include "USBSerial.h"
 #include "WCharacter.h"
+#include "WSerial.h"
 #include "WMath.h"
 #include "WString.h"
 #endif // __cplusplus
 
+
 #define clockCyclesPerMicrosecond() ( SystemCoreClock / 1000000L )
 #define clockCyclesToMicroseconds(a) ( ((a) * 1000L) / (SystemCoreClock / 1000L) )
 #define microsecondsToClockCycles(a) ( (a) * (SystemCoreClock / 1000000L) )
diff --git a/platform.txt b/platform.txt
index 0c859f36c7..fb9d25b560 100644
--- a/platform.txt
+++ b/platform.txt
@@ -67,7 +67,7 @@ compiler.arm.cmsis.ldflags="-L{runtime.tools.CMSIS-5.3.0.path}/CMSIS/Lib/GCC/" -
 
 # USB Flags
 # ---------
-build.usb_flags=-DUSBCON -DUSBD_VID={build.vid} '-DUSB_MANUFACTURER={build.usb_manufacturer}' '-DUSB_PRODUCT="{build.board}"' -DHAL_PCD_MODULE_ENABLED 
+build.usb_flags=-DUSBCON {build.usb_speed} -DUSBD_VID={build.vid} '-DUSB_MANUFACTURER={build.usb_manufacturer}' '-DUSB_PRODUCT="{build.board}"' -DHAL_PCD_MODULE_ENABLED 
 
 # Default usb manufacturer will be replaced at compile time using
 # numeric vendor ID if available or by board's specific value.
@@ -79,6 +79,7 @@ build.info.flags=-D{build.series} -DARDUINO={runtime.ide.version} -DARDUINO_{bui
 # Defaults config
 build.xSerial=-DHAL_UART_MODULE_ENABLED
 build.enable_usb=
+build.usb_speed=
 build.startup_file=
 build.flags.optimize=-Os
 build.flags.ldspecs=--specs=nano.specs