diff --git a/hardware/arduino/sam/cores/arduino/Arduino.h b/hardware/arduino/sam/cores/arduino/Arduino.h
index 00b6715b1..ec4274ccb 100644
--- a/hardware/arduino/sam/cores/arduino/Arduino.h
+++ b/hardware/arduino/sam/cores/arduino/Arduino.h
@@ -194,6 +194,7 @@ extern const PinDescription g_APinDescription[] ;
 #include "HardwareSerial.h"
 #include "wiring_pulse.h"
 
+// USB Host
 #include "Usb.h"
 
 #endif // __cplusplus
@@ -201,16 +202,13 @@ extern const PinDescription g_APinDescription[] ;
 // Include board variant
 #include "variant.h"
 
-#if defined USBCON
-  #define USB_VID            0x2341 // arduino LLC vid
-
-  #define USB_PID_LEONARDO   0x0034
-  #define USB_PID_MICRO      0x0035
-  #define USB_PID_DUE        0x003E
-
-  #include "USB/USBDesc.h"
-  #include "USB/USBCore.h"
-  #include "USB/USBAPI.h"
-#endif // if defined USBCON
+// USB Device
+#define USB_VID            0x2341 // arduino LLC vid
+#define USB_PID_LEONARDO   0x0034
+#define USB_PID_MICRO      0x0035
+#define USB_PID_DUE        0x003E
+#include "USB/USBDesc.h"
+#include "USB/USBCore.h"
+#include "USB/USBAPI.h"
 
 #endif // Arduino_h
diff --git a/hardware/arduino/sam/cores/arduino/USB/CDC.cpp b/hardware/arduino/sam/cores/arduino/USB/CDC.cpp
index 8992a2e63..5c451a5c0 100644
--- a/hardware/arduino/sam/cores/arduino/USB/CDC.cpp
+++ b/hardware/arduino/sam/cores/arduino/USB/CDC.cpp
@@ -17,8 +17,6 @@
 #include "Arduino.h"
 #include "USBAPI.h"
 
-#if defined(USBCON)
-
 #ifdef CDC_ENABLED
 
 #define CDC_SERIAL_BUFFER_SIZE	64
@@ -252,4 +250,3 @@ Serial_::operator bool()
 Serial_ Serial;
 
 #endif
-#endif /* if defined(USBCON) */
diff --git a/hardware/arduino/sam/cores/arduino/USB/HID.cpp b/hardware/arduino/sam/cores/arduino/USB/HID.cpp
index a02dbec8c..2a4e73b8c 100644
--- a/hardware/arduino/sam/cores/arduino/USB/HID.cpp
+++ b/hardware/arduino/sam/cores/arduino/USB/HID.cpp
@@ -16,7 +16,6 @@
 
 #include "Arduino.h"
 
-#if defined(USBCON)
 #ifdef HID_ENABLED
 
 //#define RAWHID_ENABLED
@@ -509,5 +508,3 @@ size_t Keyboard_::write(uint8_t c)
 }
 
 #endif
-
-#endif /* if defined(USBCON) */
diff --git a/hardware/arduino/sam/cores/arduino/USB/USBAPI.h b/hardware/arduino/sam/cores/arduino/USB/USBAPI.h
index b65d20bb8..592d3a0b1 100644
--- a/hardware/arduino/sam/cores/arduino/USB/USBAPI.h
+++ b/hardware/arduino/sam/cores/arduino/USB/USBAPI.h
@@ -19,7 +19,7 @@
 #ifndef __USBAPI__
 #define __USBAPI__
 
-#if defined __cplusplus && defined USBCON
+#if defined __cplusplus
 
 #include "RingBuffer.h"
 
@@ -214,5 +214,4 @@ void USBD_Flush(uint32_t ep);
 uint32_t USBD_Connected(void);
 
 #endif
-
-#endif /* if defined USBCON */
+#endif
diff --git a/hardware/arduino/sam/cores/arduino/USB/USBCore.cpp b/hardware/arduino/sam/cores/arduino/USB/USBCore.cpp
index 8a9d2410a..51bc6b92f 100644
--- a/hardware/arduino/sam/cores/arduino/USB/USBCore.cpp
+++ b/hardware/arduino/sam/cores/arduino/USB/USBCore.cpp
@@ -1,5 +1,3 @@
-#ifdef USBCON
-
 /* Copyright (c) 2010, Peter Barrett
 **
 ** Permission to use, copy, modify, and/or distribute this software for
@@ -20,8 +18,8 @@
 #include "USBAPI.h"
 #include <stdio.h>
 
-//#define TRACE_CORE(x)	x
-#define TRACE_CORE(x)
+#define TRACE_CORE(x)	x
+//#define TRACE_CORE(x)
 
 static const uint32_t EndPoints[] =
 {
@@ -212,14 +210,14 @@ int USBD_SendControl(uint8_t flags, const void* d, uint32_t len)
 	uint32_t sent = 0;
 	uint32_t pos = 0;
 
-	TRACE_CORE(printf("=> USBD_SendControl TOTAL len=%d\r\n", len);)
+	TRACE_CORE(printf("=> USBD_SendControl TOTAL len=%lu\r\n", len);)
 
 	if (_cmark < _cend)
 	{
 		while (len > 0)
 		{
 			sent = UDD_Send(EP0, data + pos, len);
-			TRACE_CORE(printf("=> USBD_SendControl sent=%d\r\n", sent);)
+			TRACE_CORE(printf("=> USBD_SendControl sent=%lu\r\n", sent);)
 			pos += sent;
 			len -= sent;
 		}
@@ -540,7 +538,7 @@ uint32_t USBD_Connected(void)
 //=======================================================================
 //=======================================================================
 
-//USB_ USB;
+USB_ USB;
 
 USB_::USB_()
 {
@@ -589,5 +587,3 @@ bool USB_::configured()
 void USB_::poll()
 {
 }
-
-#endif // USBCON
diff --git a/hardware/arduino/sam/cores/arduino/USB/USBCore.h b/hardware/arduino/sam/cores/arduino/USB/USBCore.h
index 68b18ff65..d4dac653e 100644
--- a/hardware/arduino/sam/cores/arduino/USB/USBCore.h
+++ b/hardware/arduino/sam/cores/arduino/USB/USBCore.h
@@ -301,5 +301,4 @@ _Pragma("pack()")
 #define D_CDCCS(_subtype,_d0,_d1)	{ 5, 0x24, _subtype, _d0, _d1 }
 #define D_CDCCS4(_subtype,_d0)		{ 4, 0x24, _subtype, _d0 }
 
-
 #endif
diff --git a/hardware/arduino/sam/cores/arduino/USB/USBDesc.h b/hardware/arduino/sam/cores/arduino/USB/USBDesc.h
index fb5895adf..275d4862e 100644
--- a/hardware/arduino/sam/cores/arduino/USB/USBDesc.h
+++ b/hardware/arduino/sam/cores/arduino/USB/USBDesc.h
@@ -60,4 +60,3 @@
 
 #define IMANUFACTURER	1
 #define IPRODUCT		2
-
diff --git a/hardware/arduino/sam/cores/arduino/main.cpp b/hardware/arduino/sam/cores/arduino/main.cpp
index 818679f18..69f25f2a5 100644
--- a/hardware/arduino/sam/cores/arduino/main.cpp
+++ b/hardware/arduino/sam/cores/arduino/main.cpp
@@ -39,9 +39,7 @@ int main( void )
 
 	delay(1);
 
-#if defined(USBCON)
-	//USB.attach();
-#endif
+	USB.attach();
 
 	setup();
 
@@ -50,5 +48,5 @@ int main( void )
 		loop();
 	}
 
-//	return 0 ;
+	return 0;
 }
diff --git a/hardware/arduino/sam/cores/arduino/validation_usb_device/build_gcc/debug.mk b/hardware/arduino/sam/cores/arduino/validation_usb_device/build_gcc/debug.mk
index d0716744a..a3cc2337a 100644
--- a/hardware/arduino/sam/cores/arduino/validation_usb_device/build_gcc/debug.mk
+++ b/hardware/arduino/sam/cores/arduino/validation_usb_device/build_gcc/debug.mk
@@ -8,7 +8,7 @@
 #
 #  This library is distributed in the hope that it will be useful,
 #  but WITHOUT ANY WARRANTY; without even the implied warranty of
-#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 #  See the GNU Lesser General Public License for more details.
 #
 #  You should have received a copy of the GNU Lesser General Public
diff --git a/hardware/arduino/sam/cores/arduino/validation_usb_device/build_gcc/test_usb_device.mk b/hardware/arduino/sam/cores/arduino/validation_usb_device/build_gcc/test_usb_device.mk
index 1fdd9b12c..336bbc609 100644
--- a/hardware/arduino/sam/cores/arduino/validation_usb_device/build_gcc/test_usb_device.mk
+++ b/hardware/arduino/sam/cores/arduino/validation_usb_device/build_gcc/test_usb_device.mk
@@ -78,6 +78,7 @@ CMSIS_CHIP_PATH=$(CMSIS_ROOT_PATH)/Device/ATMEL/$(CHIP_SERIE)
 
 ARDUINO_CORE_PATH=$(PROJECT_BASE_PATH)/..
 ARDUINO_USB_PATH=$(PROJECT_BASE_PATH)/../USB
+ARDUINO_USB_HOST_PATH=$(PROJECT_BASE_PATH)/../../../system/USBHost
 
 # Output directories
 OUTPUT_PATH = debug_$(VARIANT)
@@ -99,7 +100,8 @@ INCLUDES += -I$(SYSTEM_PATH)/libsam
 INCLUDES += -I$(CMSIS_ARM_PATH)
 INCLUDES += -I$(CMSIS_ATMEL_PATH)
 INCLUDES += -I$(CMSIS_CHIP_PATH)
-INCLUDES += -I$(PROJECT_BASE_PATH)/../USB
+INCLUDES += -I$(ARDUINO_USB_PATH)
+INCLUDES += -I$(ARDUINO_USB_HOST_PATH)
 
 #-------------------------------------------------------------------------------
 ifdef DEBUG
diff --git a/hardware/arduino/sam/cores/arduino/validation_usb_device/test_usb_device.cpp b/hardware/arduino/sam/cores/arduino/validation_usb_device/test_usb_device.cpp
index 1b8fab7d5..e6c07c7e1 100644
--- a/hardware/arduino/sam/cores/arduino/validation_usb_device/test_usb_device.cpp
+++ b/hardware/arduino/sam/cores/arduino/validation_usb_device/test_usb_device.cpp
@@ -16,8 +16,6 @@
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
 
-#if defined(USBCON)
-
 #include "variant.h"
 #include <stdio.h>
 
@@ -36,7 +34,6 @@ void loop() {
 		Serial.print(inChar);
 		Serial1.print(inChar);
 	}
+
 	delay(10);
 }
-
-#endif
diff --git a/hardware/arduino/sam/cores/arduino/validation_usb_host/test_usb_host.cpp b/hardware/arduino/sam/cores/arduino/validation_usb_host/test_usb_host.cpp
index 60583671b..a836acfd5 100644
--- a/hardware/arduino/sam/cores/arduino/validation_usb_host/test_usb_host.cpp
+++ b/hardware/arduino/sam/cores/arduino/validation_usb_host/test_usb_host.cpp
@@ -2,58 +2,49 @@
 #include <stdio.h>
 #include <hidboot.h>
 
-class KbdRptParser : public KeyboardReportParser
+class MouseRptParser : public MouseReportParser
 {
-	void PrintKey(uint8_t mod, uint8_t key);
-
 protected:
-	virtual void OnKeyDown	(uint8_t mod, uint8_t key);
-	virtual void OnKeyUp	(uint8_t mod, uint8_t key);
-	virtual void OnKeyPressed(uint8_t key);
+	virtual void OnMouseMove		(MOUSEINFO *mi);
+	virtual void OnLeftButtonUp		(MOUSEINFO *mi);
+	virtual void OnLeftButtonDown	(MOUSEINFO *mi);
+	virtual void OnRightButtonUp	(MOUSEINFO *mi);
+	virtual void OnRightButtonDown	(MOUSEINFO *mi);
+	virtual void OnMiddleButtonUp	(MOUSEINFO *mi);
+	virtual void OnMiddleButtonDown	(MOUSEINFO *mi);
 };
-
-void KbdRptParser::PrintKey(uint8_t m, uint8_t key)
+void MouseRptParser::OnMouseMove(MOUSEINFO *mi)
 {
-    MODIFIERKEYS mod;
-
-    *((uint8_t*)&mod) = m;
-    printf((mod.bmLeftCtrl   == 1) ? "C" : " ");
-    printf((mod.bmLeftShift  == 1) ? "S" : " ");
-    printf((mod.bmLeftAlt    == 1) ? "A" : " ");
-    printf((mod.bmLeftGUI    == 1) ? "G" : " ");
-
-    printf("<%c>", key);
-
-    printf((mod.bmRightCtrl   == 1) ? "C" : " ");
-    printf((mod.bmRightShift  == 1) ? "S" : " ");
-    printf((mod.bmRightAlt    == 1) ? "A" : " ");
-    printf((mod.bmRightGUI    == 1) ? "G" : " ");
+    printf("Pos={%d,%d}\r\n", mi->dX, mi->dY);
 };
-
-void KbdRptParser::OnKeyDown(uint8_t mod, uint8_t key)
+void MouseRptParser::OnLeftButtonUp (MOUSEINFO *mi)
 {
-    printf("DN ");
-    PrintKey(mod, key);
-    uint8_t c = OemToAscii(mod, key);
-
-    if (c)
-        OnKeyPressed(c);
-}
-
-void KbdRptParser::OnKeyUp(uint8_t mod, uint8_t key)
+    printf("L Butt Up\r\n");
+};
+void MouseRptParser::OnLeftButtonDown (MOUSEINFO *mi)
 {
-    printf("UP ");
-    PrintKey(mod, key);
-}
-
-void KbdRptParser::OnKeyPressed(uint8_t key)
+    printf("L Butt Dn\r\n");
+};
+void MouseRptParser::OnRightButtonUp (MOUSEINFO *mi)
 {
-    printf("ASCII: %c", key);
+    printf("R Butt Up\r\n");
+};
+void MouseRptParser::OnRightButtonDown (MOUSEINFO *mi)
+{
+    printf("R Butt Dn\r\n");
+};
+void MouseRptParser::OnMiddleButtonUp (MOUSEINFO *mi)
+{
+    printf("M Butt Up\r\n");
+};
+void MouseRptParser::OnMiddleButtonDown (MOUSEINFO *mi)
+{
+    printf("M Butt Dn\r\n");
 };
 
 USBHost Usb;
-HIDBoot<HID_PROTOCOL_KEYBOARD> Kbd(&Usb);
-KbdRptParser Prs;
+HIDBoot<HID_PROTOCOL_MOUSE> HostMouse(&Usb);
+MouseRptParser Prs;
 
 void setup()
 {
@@ -61,7 +52,7 @@ void setup()
 	printf("\r\nProgram started:\r\n");
 	delay(200);
 
-    Kbd.SetReportParser(0, (HIDReportParser*)&Prs);
+    HostMouse.SetReportParser(0,(HIDReportParser*)&Prs);
 }
 
 void loop()
diff --git a/hardware/arduino/sam/system/libsam/source/uotghs_device.c b/hardware/arduino/sam/system/libsam/source/uotghs_device.c
index 2f8bb881b..cf439a5d0 100644
--- a/hardware/arduino/sam/system/libsam/source/uotghs_device.c
+++ b/hardware/arduino/sam/system/libsam/source/uotghs_device.c
@@ -32,8 +32,8 @@
 
 #if SAM3XA_SERIES
 
-//#define TRACE_UOTGHS(x)	x
-#define TRACE_UOTGHS(x)
+#define TRACE_UOTGHS_DEVICE(x)	x
+//#define TRACE_UOTGHS_DEVICE(x)
 
 extern void (*gpf_isr)(void);
 
@@ -83,8 +83,9 @@ uint32_t UDD_Init(void)
 	//while (!Is_otg_clock_usable())
 	//	;
 
+	// Enable High Speed
 	udd_low_speed_disable();
-	udd_high_speed_disable();
+	udd_high_speed_enable();
 
 	//otg_ack_vbus_transition();
 	// Force Vbus interrupt in case of Vbus always with a high level
@@ -102,7 +103,7 @@ void UDD_Attach(void)
 {
 	irqflags_t flags = cpu_irq_save();
 
-	TRACE_UOTGHS(printf("=> UDD_Attach\r\n");)
+	TRACE_UOTGHS_DEVICE(printf("=> UDD_Attach\r\n");)
 
 	otg_unfreeze_clock();
 
@@ -121,7 +122,7 @@ void UDD_Attach(void)
 
 void UDD_Detach(void)
 {
-	TRACE_UOTGHS(printf("=> UDD_Detach\r\n");)
+	TRACE_UOTGHS_DEVICE(printf("=> UDD_Detach\r\n");)
 	UOTGHS->UOTGHS_DEVCTRL |= UOTGHS_DEVCTRL_DETACH;
 }
 
@@ -129,7 +130,7 @@ void UDD_InitEP( uint32_t ul_ep_nb, uint32_t ul_ep_cfg )
 {
 	ul_ep_nb = ul_ep_nb & 0xF; // EP range is 0..9, hence mask is 0xF.
 
-	TRACE_UOTGHS(printf("=> UDD_InitEP : init EP %d\r\n", ul_ep_nb);)
+	TRACE_UOTGHS_DEVICE(printf("=> UDD_InitEP : init EP %lu\r\n", ul_ep_nb);)
 
 	// Configure EP
 	UOTGHS->UOTGHS_DEVEPTCFG[ul_ep_nb] = ul_ep_cfg;
@@ -137,7 +138,7 @@ void UDD_InitEP( uint32_t ul_ep_nb, uint32_t ul_ep_cfg )
 	udd_enable_endpoint(ul_ep_nb);
 
 	if (!Is_udd_endpoint_configured(ul_ep_nb)) {
-		TRACE_UOTGHS(printf("=> UDD_InitEP : ERROR FAILED TO INIT EP %d\r\n", ul_ep_nb);)
+		TRACE_UOTGHS_DEVICE(printf("=> UDD_InitEP : ERROR FAILED TO INIT EP %lu\r\n", ul_ep_nb);)
 	}
 }
 
@@ -154,7 +155,7 @@ void UDD_InitEndpoints(const uint32_t* eps_table, const uint32_t ul_eps_table_si
 		udd_enable_endpoint(ul_ep_nb);
 
 		if (!Is_udd_endpoint_configured(ul_ep_nb)) {
-			TRACE_UOTGHS(printf("=> UDD_InitEP : ERROR FAILED TO INIT EP %d\r\n", ul_ep_nb);)
+			TRACE_UOTGHS_DEVICE(printf("=> UDD_InitEP : ERROR FAILED TO INIT EP %lu\r\n", ul_ep_nb);)
 		}
 	}
 }
@@ -175,7 +176,7 @@ void UDD_WaitOUT(void)
 // Send packet.
 void UDD_ClearIN(void)
 {
-	TRACE_UOTGHS(printf("=> UDD_ClearIN: sent %d bytes\r\n", ul_send_fifo_ptr[EP0]);)
+	TRACE_UOTGHS_DEVICE(printf("=> UDD_ClearIN: sent %lu bytes\r\n", ul_send_fifo_ptr[EP0]);)
 
 	UOTGHS->UOTGHS_DEVEPTICR[EP0] = UOTGHS_DEVEPTICR_TXINIC;
 	ul_send_fifo_ptr[EP0] = 0;
@@ -212,7 +213,7 @@ uint32_t UDD_Send(uint32_t ep, const void* data, uint32_t len)
 	uint8_t *ptr_dest = (uint8_t *) &udd_get_endpoint_fifo_access8(ep);
 	uint32_t i;
 
-	TRACE_UOTGHS(printf("=> UDD_Send (1): ep=%d ul_send_fifo_ptr=%d len=%d\r\n", ep, ul_send_fifo_ptr[ep], len);)
+	TRACE_UOTGHS_DEVICE(printf("=> UDD_Send (1): ep=%lu ul_send_fifo_ptr=%lu len=%lu\r\n", ep, ul_send_fifo_ptr[ep], len);)
 
 	if (ep == EP0)
 	{
@@ -233,7 +234,7 @@ uint32_t UDD_Send(uint32_t ep, const void* data, uint32_t len)
 
 	if (ep == EP0)
 	{
-		TRACE_UOTGHS(printf("=> UDD_Send (2): ep=%d ptr_dest=%d maxlen=%d\r\n", ep, ul_send_fifo_ptr[ep], EP0_SIZE);)
+		TRACE_UOTGHS_DEVICE(printf("=> UDD_Send (2): ep=%lu ptr_dest=%lu maxlen=%d\r\n", ep, ul_send_fifo_ptr[ep], EP0_SIZE);)
 		if (ul_send_fifo_ptr[ep] == EP0_SIZE)
 		{
 			UDD_ClearIN();	// Fifo is full, release this packet
@@ -256,7 +257,7 @@ void UDD_Send8(uint32_t ep,  uint8_t data )
 {
 	uint8_t *ptr_dest = (uint8_t *) &udd_get_endpoint_fifo_access8(ep);
 
-	TRACE_UOTGHS(printf("=> UDD_Send8 : ul_send_fifo_ptr=%d data=0x%x\r\n", ul_send_fifo_ptr[ep], data);)
+	TRACE_UOTGHS_DEVICE(printf("=> UDD_Send8 : ul_send_fifo_ptr=%lu data=0x%x\r\n", ul_send_fifo_ptr[ep], data);)
 
 	ptr_dest[ul_send_fifo_ptr[ep]] = data;
 	ul_send_fifo_ptr[ep] += 1;
@@ -267,7 +268,7 @@ uint8_t UDD_Recv8(uint32_t ep)
 	uint8_t *ptr_dest = (uint8_t *) &udd_get_endpoint_fifo_access8(ep);
 	uint8_t data = ptr_dest[ul_recv_fifo_ptr[ep]];
 
-	TRACE_UOTGHS(printf("=> UDD_Recv8 : ul_recv_fifo_ptr=%d\r\n", ul_recv_fifo_ptr[ep]);)
+	TRACE_UOTGHS_DEVICE(printf("=> UDD_Recv8 : ul_recv_fifo_ptr=%lu\r\n", ul_recv_fifo_ptr[ep]);)
 
 	ul_recv_fifo_ptr[ep] += 1;
 	return data;
@@ -299,7 +300,7 @@ uint32_t UDD_FifoByteCount(uint32_t ep)
 
 void UDD_ReleaseRX(uint32_t ep)
 {
-	TRACE_UOTGHS(puts("=> UDD_ReleaseRX\r\n");)
+	TRACE_UOTGHS_DEVICE(puts("=> UDD_ReleaseRX\r\n");)
 	UOTGHS->UOTGHS_DEVEPTICR[ep] = (UOTGHS_DEVEPTICR_NAKOUTIC | UOTGHS_DEVEPTICR_RXOUTIC);
 	UOTGHS->UOTGHS_DEVEPTIDR[ep] = UOTGHS_DEVEPTIDR_FIFOCONC;
 	ul_recv_fifo_ptr[ep] = 0;
@@ -307,7 +308,7 @@ void UDD_ReleaseRX(uint32_t ep)
 
 void UDD_ReleaseTX(uint32_t ep)
 {
-	TRACE_UOTGHS(printf("=> UDD_ReleaseTX ep=%d\r\n", ep);)
+	TRACE_UOTGHS_DEVICE(printf("=> UDD_ReleaseTX ep=%lu\r\n", ep);)
 	UOTGHS->UOTGHS_DEVEPTICR[ep] = (UOTGHS_DEVEPTICR_NAKINIC | UOTGHS_DEVEPTICR_RXOUTIC | UOTGHS_DEVEPTICR_TXINIC);
 	UOTGHS->UOTGHS_DEVEPTIDR[ep] = UOTGHS_DEVEPTIDR_FIFOCONC;
 	ul_send_fifo_ptr[ep] = 0;
@@ -321,7 +322,7 @@ uint32_t UDD_ReadWriteAllowed(uint32_t ep)
 
 void UDD_SetAddress(uint32_t addr)
 {
-	TRACE_UOTGHS(printf("=> UDD_SetAddress : setting address to %d\r\n", addr);)
+	TRACE_UOTGHS_DEVICE(printf("=> UDD_SetAddress : setting address to %lu\r\n", addr);)
 
 	udd_configure_address(addr);
 	udd_enable_address();
diff --git a/hardware/arduino/sam/system/libsam/source/uotghs_host.c b/hardware/arduino/sam/system/libsam/source/uotghs_host.c
index 1090c774d..64b75a8ca 100644
--- a/hardware/arduino/sam/system/libsam/source/uotghs_host.c
+++ b/hardware/arduino/sam/system/libsam/source/uotghs_host.c
@@ -32,8 +32,8 @@
 
 #if SAM3XA_SERIES
 
-#define TRACE_UOTGHS(x)	x
-//#define TRACE_UOTGHS(x)
+#define TRACE_UOTGHS_HOST(x)	x
+//#define TRACE_UOTGHS_HOST(x)
 
 extern void (*gpf_isr)(void);
 
@@ -43,7 +43,7 @@ static void UHD_ISR(void)
 {
 	// Manage dis/connection event
 	if (Is_uhd_disconnection() && Is_uhd_disconnection_int_enabled()) {
-		TRACE_UOTGHS(printf(">>> UHD_ISR : Disconnection INT\r\n");)
+		TRACE_UOTGHS_HOST(printf(">>> UHD_ISR : Disconnection INT\r\n");)
 		uhd_ack_disconnection();
 		uhd_disable_disconnection_int();
 		// Stop reset signal, in case of disconnection during reset
@@ -59,7 +59,7 @@ static void UHD_ISR(void)
 		return;
 	}
 	if (Is_uhd_connection() && Is_uhd_connection_int_enabled()) {
-		TRACE_UOTGHS(printf(">>> UHD_ISR : Connection INT\r\n");)
+		TRACE_UOTGHS_HOST(printf(">>> UHD_ISR : Connection INT\r\n");)
 		uhd_ack_connection();
 		uhd_disable_connection_int();
 		uhd_ack_disconnection();
@@ -72,7 +72,7 @@ static void UHD_ISR(void)
 	// Manage Vbus error
 	if (Is_uhd_vbus_error_interrupt())
 	{
-		TRACE_UOTGHS(printf(">>> UHD_ISR : VBUS error INT\r\n");)
+		TRACE_UOTGHS_HOST(printf(">>> UHD_ISR : VBUS error INT\r\n");)
 		uhd_ack_vbus_error_interrupt();
 		uhd_state = UHD_STATE_ERROR;
 		return;
@@ -89,23 +89,23 @@ static void UHD_ISR(void)
 		otg_ack_vbus_transition();
 		if (Is_otg_vbus_high())
 		{
-			TRACE_UOTGHS(printf(">>> UHD_ISR : VBUS transition INT : UHD_STATE_DISCONNECT\r\n");)
+			TRACE_UOTGHS_HOST(printf(">>> UHD_ISR : VBUS transition INT : UHD_STATE_DISCONNECT\r\n");)
 			uhd_state = UHD_STATE_DISCONNECTED;
 		}
 		else
 		{
-			TRACE_UOTGHS(printf(">>> UHD_ISR : VBUS transition INT : UHD_STATE_NO_VBUS\r\n");)
+			TRACE_UOTGHS_HOST(printf(">>> UHD_ISR : VBUS transition INT : UHD_STATE_NO_VBUS\r\n");)
 			otg_freeze_clock();
 			uhd_state = UHD_STATE_NO_VBUS;
 		}
-		TRACE_UOTGHS(printf(">>> UHD_ISR : VBUS transition INT : done.\r\n");)
+		TRACE_UOTGHS_HOST(printf(">>> UHD_ISR : VBUS transition INT : done.\r\n");)
 		return;
 	}
 
 	// Other errors
 	if (Is_uhd_errors_interrupt())
 	{
-		TRACE_UOTGHS(printf(">>> UHD_ISR : Other error INT\r\n");)
+		TRACE_UOTGHS_HOST(printf(">>> UHD_ISR : Other error INT\r\n");)
 		uhd_ack_errors_interrupt();
 		return;
 	}
@@ -228,7 +228,7 @@ uint32_t UHD_EP0_Alloc(uint32_t ul_add, uint32_t ul_ep_size)
 {
 	if (ul_ep_size < 8)
 	{
-		TRACE_UOTGHS(printf("/!\\ UHD_EP0_Alloc : incorrect pipe size!\r\n");)
+		TRACE_UOTGHS_HOST(printf("/!\\ UHD_EP0_Alloc : incorrect pipe size!\r\n");)
 		return 1;
 	}
 
@@ -251,7 +251,7 @@ uint32_t UHD_EP0_Alloc(uint32_t ul_add, uint32_t ul_ep_size)
 
 	if (!Is_uhd_pipe_configured(0))
 	{
-		TRACE_UOTGHS(printf("/!\\ UHD_EP0_Alloc : incorrect pipe settings!\r\n");)
+		TRACE_UOTGHS_HOST(printf("/!\\ UHD_EP0_Alloc : incorrect pipe settings!\r\n");)
 		uhd_disable_pipe(0);
 		return 1;
 	}
@@ -264,11 +264,21 @@ uint32_t UHD_EP0_Alloc(uint32_t ul_add, uint32_t ul_ep_size)
 /**
  * \brief Allocate FIFO for the specified pipe.
  *
+ * \param ul_add Address of remote device for pipe 0.
+ * \param ul_ep_size Actual size of the FIFO in bytes.
+ *
  * \retval 0 success.
  * \retval 1 error.
  */
 uint32_t UHD_EP_Alloc(uint32_t ul_pipe, uint32_t ul_addr, uint32_t ul_interval, uint32_t ul_type, uint32_t ul_dir, uint32_t ul_maxsize, uint32_t ul_bank)
 {
+
+/*
+ * Warning: this is a first implementation, pipe allocation is very limited.
+ * We should probably check maxsize and if maxsize > current size, then realloc with maxsize.
+ * If pipe type is changed, a pipe reset and re-configuration is required.
+ */
+
 	if (Is_uhd_pipe_enabled(ul_pipe))
 	{
 		// Pipe is already allocated
@@ -355,7 +365,7 @@ void UHD_EP_Write(uint32_t ul_ep, uint32_t ul_size, uint8_t* data)
 	if (!Is_uhd_pipe_enabled(ul_ep))
 	{
 		// Endpoint not valid
-		TRACE_UOTGHS(printf("/!\\ UHD_EP_Send : pipe is not enabled!\r\n");)
+		TRACE_UOTGHS_HOST(printf("/!\\ UHD_EP_Send : pipe is not enabled!\r\n");)
 		return;
 	}
 
@@ -370,7 +380,7 @@ void UHD_EP_Send(uint32_t ul_ep, uint32_t ul_token_type)
 	if (!Is_uhd_pipe_enabled(ul_ep))
 	{
 		// Endpoint not valid
-		TRACE_UOTGHS(printf("/!\\ UHD_EP_Send : pipe %lu is not enabled!\r\n", ul_ep);)
+		TRACE_UOTGHS_HOST(printf("/!\\ UHD_EP_Send : pipe %lu is not enabled!\r\n", ul_ep);)
 		return;
 	}
 
diff --git a/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a b/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a
index 1a9194c14..ef35d08c6 100644
Binary files a/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a and b/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a differ
diff --git a/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a.txt b/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a.txt
index 86c0b679d..d4f904640 100644
--- a/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a.txt
+++ b/hardware/arduino/sam/variants/arduino_due_x/libsam_sam3x8e_gcc_rel.a.txt
@@ -376,10 +376,12 @@ uotghs_device.o:
 00000000 T UDD_WaitOUT
          U g_interrupt_enabled
          U gpf_isr
+         U iprintf
          U pmc_enable_periph_clk
          U pmc_enable_udpck
          U pmc_enable_upll_clock
          U pmc_switch_udpck_to_upllck
+         U puts
 00000000 b ul_recv_fifo_ptr
 00000000 b ul_send_fifo_ptr
 
diff --git a/hardware/arduino/sam/variants/arduino_due_x/variant.h b/hardware/arduino/sam/variants/arduino_due_x/variant.h
index 884a4d01f..faf354a42 100644
--- a/hardware/arduino/sam/variants/arduino_due_x/variant.h
+++ b/hardware/arduino/sam/variants/arduino_due_x/variant.h
@@ -23,9 +23,6 @@
  *        Headers
  *----------------------------------------------------------------------------*/
 
-// We have native USB on this variant
-#define USBCON
-
 #include "Arduino.h"
 #ifdef __cplusplus
 #include "UARTClass.h"