12 files changed, 340 insertions, 115 deletions

diff --git a/cores/arduino/CDC.cpp b/cores/arduino/CDC.cpp
index 14a0eae..1ee3a48 100644
--- a/cores/arduino/CDC.cpp
+++ b/cores/arduino/CDC.cpp
@@ -23,12 +23,20 @@
 #if defined(USBCON)
 #ifdef CDC_ENABLED
 
-void Reboot()
+#if (RAMEND < 1000)
+#define SERIAL_BUFFER_SIZE 16
+#else
+#define SERIAL_BUFFER_SIZE 64
+#endif
+
+struct ring_buffer
 {
-	USB.detach();
-	cli();
-	asm volatile("jmp 0x7800");		// jump to bootloader - DiskLoader takes up last 2 kB
-}
+	unsigned char buffer[SERIAL_BUFFER_SIZE];
+	volatile int head;
+	volatile int tail;
+};
+
+ring_buffer cdc_rx_buffer = { { 0 }, 0, 0};
 
 typedef struct
 {
@@ -92,9 +100,28 @@ bool WEAK CDC_Setup(Setup& setup)
 
 		if (CDC_SET_CONTROL_LINE_STATE == r)
 		{
-			if (0 != _usbLineInfo.lineState && 1200 == _usbLineInfo.dwDTERate)	// auto-reset is triggered when the port, already open at 1200 bps, is closed
-				Reboot();
 			_usbLineInfo.lineState = setup.wValueL;
+
+			// auto-reset into the bootloader is triggered when the port, already 
+			// open at 1200 bps, is closed.  this is the signal to start the watchdog
+			// with a relatively long period so it can finish housekeeping tasks
+			// like servicing endpoints before the sketch ends
+			if (1200 == _usbLineInfo.dwDTERate) {
+				// We check DTR state to determine if host port is open (bit 0 of lineState).
+				if ((_usbLineInfo.lineState & 0x01) == 0) {
+					*(uint16_t *)0x0800 = 0x7777;
+					wdt_enable(WDTO_120MS);
+				} else {
+					// Most OSs do some intermediate steps when configuring ports and DTR can
+					// twiggle more than once before stabilizing.
+					// To avoid spurious resets we set the watchdog to 250ms and eventually
+					// cancel if DTR goes back high.
+	
+					wdt_disable();
+					wdt_reset();
+					*(uint16_t *)0x0800 = 0x0;
+				}
+			}
 			return true;
 		}
 	}
@@ -111,33 +138,49 @@ void Serial_::end(void)
 {
 }
 
+void Serial_::accept(void) 
+{
+	ring_buffer *buffer = &cdc_rx_buffer;
+	int c = USB_Recv(CDC_RX); 
+	int i = (unsigned int)(buffer->head+1) % SERIAL_BUFFER_SIZE;
+	
+	// if we should be storing the received character into the location
+	// just before the tail (meaning that the head would advance to the
+	// current location of the tail), we're about to overflow the buffer
+	// and so we don't write the character or advance the head.
+	if (i != buffer->tail) {
+		buffer->buffer[buffer->head] = c;
+		buffer->head = i;
+	}
+}
+
 int Serial_::available(void)
 {
-	u8 avail = USB_Available(CDC_RX);
-	if (_serialPeek != -1)
-		avail++;
-	return avail;
+	ring_buffer *buffer = &cdc_rx_buffer;
+	return (unsigned int)(SERIAL_BUFFER_SIZE + buffer->head - buffer->tail) % SERIAL_BUFFER_SIZE;
 }
 
-//	peek is nasty
 int Serial_::peek(void)
 {
-	if (_serialPeek == -1)
-		_serialPeek = read();
-	return _serialPeek;
+	ring_buffer *buffer = &cdc_rx_buffer;
+	if (buffer->head == buffer->tail) {
+		return -1;
+	} else {
+		return buffer->buffer[buffer->tail];
+	}
 }
 
 int Serial_::read(void)
 {
-	int c;
-	if (_serialPeek != -1)
-	{
-		c = _serialPeek;
-		_serialPeek = -1;
+	ring_buffer *buffer = &cdc_rx_buffer;
+	// if the head isn't ahead of the tail, we don't have any characters
+	if (buffer->head == buffer->tail) {
+		return -1;
 	} else {
-		c = USB_Recv(CDC_RX);
-	}
-	return c;
+		unsigned char c = buffer->buffer[buffer->tail];
+		buffer->tail = (unsigned int)(buffer->tail + 1) % SERIAL_BUFFER_SIZE;
+		return c;
+	}	
 }
 
 void Serial_::flush(void)
@@ -169,7 +212,22 @@ size_t Serial_::write(uint8_t c)
 	return 0;
 }
 
+// This operator is a convenient way for a sketch to check whether the
+// port has actually been configured and opened by the host (as opposed
+// to just being connected to the host).  It can be used, for example, in 
+// setup() before printing to ensure that an application on the host is
+// actually ready to receive and display the data.
+// We add a short delay before returning to fix a bug observed by Federico
+// where the port is configured (lineState != 0) but not quite opened.
+Serial_::operator bool() {
+	bool result = false;
+	if (_usbLineInfo.lineState > 0) 
+		result = true;
+	delay(10);
+	return result;
+}
+
 Serial_ Serial;
 
 #endif
-#endif /* if defined(USBCON) */
\ No newline at end of file
+#endif /* if defined(USBCON) */
diff --git a/cores/arduino/HID.cpp b/cores/arduino/HID.cpp
index 8ed1566..ac63608 100644
--- a/cores/arduino/HID.cpp
+++ b/cores/arduino/HID.cpp
@@ -144,7 +144,6 @@ u8 _hid_protocol = 1;
 u8 _hid_idle = 1;
 
 #define WEAK __attribute__ ((weak))
-#define WEAK 
 
 int WEAK HID_GetInterface(u8* interfaceNum)
 {
@@ -202,7 +201,15 @@ bool WEAK HID_Setup(Setup& setup)
 //================================================================================
 //	Mouse
 
-Mouse_::Mouse_() : _buttons(0)
+Mouse_::Mouse_(void) : _buttons(0)
+{
+}
+
+void Mouse_::begin(void) 
+{
+}
+
+void Mouse_::end(void) 
 {
 }
 
@@ -245,7 +252,7 @@ void Mouse_::release(uint8_t b)
 
 bool Mouse_::isPressed(uint8_t b)
 {
-	if (b & _buttons > 0) 
+	if ((b & _buttons) > 0) 
 		return true;
 	return false;
 }
@@ -254,18 +261,21 @@ bool Mouse_::isPressed(uint8_t b)
 //================================================================================
 //	Keyboard
 
-Keyboard_::Keyboard_() : _keyMap(0)
+Keyboard_::Keyboard_(void) 
 {
 }
 
-void Keyboard_::sendReport(KeyReport* keys)
+void Keyboard_::begin(void) 
+{
+}
+
+void Keyboard_::end(void) 
 {
-	HID_SendReport(2,keys,sizeof(KeyReport));
 }
 
-void Keyboard_::setKeyMap(KeyMap* keyMap)
+void Keyboard_::sendReport(KeyReport* keys)
 {
-	_keyMap = keyMap;
+	HID_SendReport(2,keys,sizeof(KeyReport));
 }
 
 extern
@@ -406,41 +416,105 @@ const uint8_t _asciimap[128] =
 };
 
 uint8_t USBPutChar(uint8_t c);
-size_t Keyboard_::write(uint8_t c)
+
+// press() adds the specified key (printing, non-printing, or modifier)
+// to the persistent key report and sends the report.  Because of the way 
+// USB HID works, the host acts like the key remains pressed until we 
+// call release(), releaseAll(), or otherwise clear the report and resend.
+size_t Keyboard_::press(uint8_t k) 
 {
-	// Keydown
-	{
-		KeyReport keys = {0};
-		if (_keyMap)
-			_keyMap->charToKey(c,&keys);
-		else
-		{
-			if (c >= 128) {
-				setWriteError();
-				return 0;
-			}
-			c = pgm_read_byte(_asciimap + c);
-			if (!c) {
-				setWriteError();
-				return 0;
-			}
-			if (c & 0x80)
-			{
-				keys.modifiers |= KEY_MODIFIER_LEFT_SHIFT;
-				c &= 0x7F;
+	uint8_t i;
+	if (k >= 136) {			// it's a non-printing key (not a modifier)
+		k = k - 136;
+	} else if (k >= 128) {	// it's a modifier key
+		_keyReport.modifiers |= (1<<(k-128));
+		k = 0;
+	} else {				// it's a printing key
+		k = pgm_read_byte(_asciimap + k);
+		if (!k) {
+			setWriteError();
+			return 0;
+		}
+		if (k & 0x80) {						// it's a capital letter or other character reached with shift
+			_keyReport.modifiers |= 0x02;	// the left shift modifier
+			k &= 0x7F;
+		}
+	}
+	
+	// Add k to the key report only if it's not already present
+	// and if there is an empty slot.
+	if (_keyReport.keys[0] != k && _keyReport.keys[1] != k && 
+		_keyReport.keys[2] != k && _keyReport.keys[3] != k &&
+		_keyReport.keys[4] != k && _keyReport.keys[5] != k) {
+		
+		for (i=0; i<6; i++) {
+			if (_keyReport.keys[i] == 0x00) {
+				_keyReport.keys[i] = k;
+				break;
 			}
-			keys.keys[0] = c;
 		}
-		sendReport(&keys);
+		if (i == 6) {
+			setWriteError();
+			return 0;
+		}	
 	}
-	//	Keyup
-	{
-		KeyReport keys = {0};
-		sendReport(&keys);
+	sendReport(&_keyReport);
+	return 1;
+}
+
+// release() takes the specified key out of the persistent key report and
+// sends the report.  This tells the OS the key is no longer pressed and that
+// it shouldn't be repeated any more.
+size_t Keyboard_::release(uint8_t k) 
+{
+	uint8_t i;
+	if (k >= 136) {			// it's a non-printing key (not a modifier)
+		k = k - 136;
+	} else if (k >= 128) {	// it's a modifier key
+		_keyReport.modifiers &= ~(1<<(k-128));
+		k = 0;
+	} else {				// it's a printing key
+		k = pgm_read_byte(_asciimap + k);
+		if (!k) {
+			return 0;
+		}
+		if (k & 0x80) {							// it's a capital letter or other character reached with shift
+			_keyReport.modifiers &= ~(0x02);	// the left shift modifier
+			k &= 0x7F;
+		}
 	}
+	
+	// Test the key report to see if k is present.  Clear it if it exists.
+	// Check all positions in case the key is present more than once (which it shouldn't be)
+	for (i=0; i<6; i++) {
+		if (0 != k && _keyReport.keys[i] == k) {
+			_keyReport.keys[i] = 0x00;
+		}
+	}
+
+	sendReport(&_keyReport);
 	return 1;
 }
 
+void Keyboard_::releaseAll(void)
+{
+	_keyReport.keys[0] = 0;
+	_keyReport.keys[1] = 0;	
+	_keyReport.keys[2] = 0;
+	_keyReport.keys[3] = 0;	
+	_keyReport.keys[4] = 0;
+	_keyReport.keys[5] = 0;	
+	_keyReport.modifiers = 0;
+	sendReport(&_keyReport);
+}
+
+size_t Keyboard_::write(uint8_t c)
+{	
+	uint8_t p = press(c);		// Keydown
+	uint8_t r = release(c);		// Keyup
+	return (p);					// just return the result of press() since release() almost always returns 1
+}
+
 #endif
 
 #endif /* if defined(USBCON) */
\ No newline at end of file
diff --git a/cores/arduino/HardwareSerial.cpp b/cores/arduino/HardwareSerial.cpp
index 9985b78..f40ddee 100644
--- a/cores/arduino/HardwareSerial.cpp
+++ b/cores/arduino/HardwareSerial.cpp
@@ -398,6 +398,10 @@ size_t HardwareSerial::write(uint8_t c)
   return 1;
 }
 
+HardwareSerial::operator bool() {
+	return true;
+}
+
 // Preinstantiate Objects //////////////////////////////////////////////////////
 
 #if defined(UBRRH) && defined(UBRRL)
diff --git a/cores/arduino/HardwareSerial.h b/cores/arduino/HardwareSerial.h
index 176abe1..bf4924c 100644
--- a/cores/arduino/HardwareSerial.h
+++ b/cores/arduino/HardwareSerial.h
@@ -57,6 +57,7 @@ class HardwareSerial : public Stream
     virtual void flush(void);
     virtual size_t write(uint8_t);
     using Print::write; // pull in write(str) and write(buf, size) from Print
+    operator bool();
 };
 
 #if defined(UBRRH) || defined(UBRR0H)
diff --git a/cores/arduino/USBAPI.h b/cores/arduino/USBAPI.h
index 26a2032..d5abdb6 100644
--- a/cores/arduino/USBAPI.h
+++ b/cores/arduino/USBAPI.h
@@ -9,17 +9,17 @@
 //================================================================================
 //	USB
 
-class USB_
+class USBDevice_
 {
 public:
-	USB_();
+	USBDevice_();
 	bool configured();
 
 	void attach();
 	void detach();	// Serial port goes down too...
 	void poll();
 };
-extern USB_ USB;
+extern USBDevice_ USBDevice;
 
 //================================================================================
 //================================================================================
@@ -27,15 +27,19 @@ extern USB_ USB;
 
 class Serial_ : public Stream
 {
+private:
+	ring_buffer *_cdc_rx_buffer;
 public:
 	void begin(uint16_t baud_count);
 	void end(void);
 
 	virtual int available(void);
+	virtual void accept(void);
 	virtual int peek(void);
 	virtual int read(void);
 	virtual void flush(void);
 	virtual size_t write(uint8_t);
+	operator bool();
 };
 extern Serial_ Serial;
 
@@ -54,12 +58,14 @@ private:
 	uint8_t _buttons;
 	void buttons(uint8_t b);
 public:
-	Mouse_();
+	Mouse_(void);
+	void begin(void);
+	void end(void);
 	void click(uint8_t b = MOUSE_LEFT);
 	void move(signed char x, signed char y, signed char wheel = 0);	
 	void press(uint8_t b = MOUSE_LEFT);		// press LEFT by default
 	void release(uint8_t b = MOUSE_LEFT);	// release LEFT by default
-	bool isPressed(uint8_t b = MOUSE_ALL);	// check all buttons by default
+	bool isPressed(uint8_t b = MOUSE_LEFT);	// check LEFT by default
 };
 extern Mouse_ Mouse;
 
@@ -67,14 +73,42 @@ extern Mouse_ Mouse;
 //================================================================================
 //	Keyboard
 
-#define KEY_MODIFIER_LEFT_CTRL		0x01
-#define KEY_MODIFIER_LEFT_SHIFT		0x02
-#define KEY_MODIFIER_LEFT_ALT		0x04
-#define KEY_MODIFIER_LEFT_GUI		0x08
-#define KEY_MODIFIER_RIGHT_CTRL		0x010
-#define KEY_MODIFIER_RIGHT_SHIFT	0x020
-#define KEY_MODIFIER_RIGHT_ALT		0x040
-#define KEY_MODIFIER_RIGHT_GUI		0x080
+#define KEY_LEFT_CTRL		0x80
+#define KEY_LEFT_SHIFT		0x81
+#define KEY_LEFT_ALT		0x82
+#define KEY_LEFT_GUI		0x83
+#define KEY_RIGHT_CTRL		0x84
+#define KEY_RIGHT_SHIFT		0x85
+#define KEY_RIGHT_ALT		0x86
+#define KEY_RIGHT_GUI		0x87
+
+#define KEY_UP_ARROW		0xDA
+#define KEY_DOWN_ARROW		0xD9
+#define KEY_LEFT_ARROW		0xD8
+#define KEY_RIGHT_ARROW		0xD7
+#define KEY_BACKSPACE		0xB2
+#define KEY_TAB				0xB3
+#define KEY_RETURN			0xB0
+#define KEY_ESC				0xB1
+#define KEY_INSERT			0xD1
+#define KEY_DELETE			0xD4
+#define KEY_PAGE_UP			0xD3
+#define KEY_PAGE_DOWN		0xD6
+#define KEY_HOME			0xD2
+#define KEY_END				0xD5
+#define KEY_CAPS_LOCK		0xC1
+#define KEY_F1				0xC2
+#define KEY_F2				0xC3
+#define KEY_F3				0xC4
+#define KEY_F4				0xC5
+#define KEY_F5				0xC6
+#define KEY_F6				0xC7
+#define KEY_F7				0xC8
+#define KEY_F8				0xC9
+#define KEY_F9				0xCA
+#define KEY_F10				0xCB
+#define KEY_F11				0xCC
+#define KEY_F12				0xCD
 
 //	Low level key report: up to 6 keys and shift, ctrl etc at once
 typedef struct
@@ -84,24 +118,19 @@ typedef struct
 	uint8_t keys[6];
 } KeyReport;
 
-//	Map a character into a key report
-//	Called from Print to map text to keycodes
-class KeyMap
-{
-public:
-	virtual void charToKey(int c, KeyReport* keyReport) = 0;
-};
-
-//	
 class Keyboard_ : public Print
 {
 private:
-	KeyMap* _keyMap;
+	KeyReport _keyReport;
 	void sendReport(KeyReport* keys);
-	void setKeyMap(KeyMap* keyMap);	
 public:
-	Keyboard_();
-	virtual size_t write(uint8_t);
+	Keyboard_(void);
+	void begin(void);
+	void end(void);
+	virtual size_t write(uint8_t k);
+	virtual size_t press(uint8_t k);
+	virtual size_t release(uint8_t k);
+	virtual void releaseAll(void);
 };
 extern Keyboard_ Keyboard;
 
diff --git a/cores/arduino/USBCore.cpp b/cores/arduino/USBCore.cpp
index 398bc73..6766be6 100644
--- a/cores/arduino/USBCore.cpp
+++ b/cores/arduino/USBCore.cpp
@@ -51,16 +51,20 @@ const u16 STRING_LANGUAGE[2] = {
 
 const u16 STRING_IPRODUCT[17] = {
 	(3<<8) | (2+2*16),
-#if USB_PID == USB_PID_LEONARDO	
+#if USB_PID == 0x8036	
 	'A','r','d','u','i','n','o',' ','L','e','o','n','a','r','d','o'
-#elif USB_PID == USB_PID_MICRO
-	'A','r','d','u','i','n','o',' ','M','i','c','r','o',' ',' ',' '
+#else
+	'U','S','B',' ','I','O',' ','B','o','a','r','d',' ',' ',' ',' '
 #endif
 };
 
 const u16 STRING_IMANUFACTURER[12] = {
 	(3<<8) | (2+2*11),
+#if USB_VID == 0x2341
 	'A','r','d','u','i','n','o',' ','L','L','C'
+#else
+	'U','n','k','n','o','w','n',' ',' ',' ',' '
+#endif
 };
 
 #ifdef CDC_ENABLED
@@ -599,6 +603,8 @@ ISR(USB_GEN_vect)
 	{
 #ifdef CDC_ENABLED
 		USB_Flush(CDC_TX);				// Send a tx frame if found
+		while (USB_Available(CDC_RX))	// Handle received bytes (if any)
+			Serial.accept();
 #endif
 		
 		// check whether the one-shot period has elapsed.  if so, turn off the LED
@@ -621,13 +627,13 @@ u8 USBConnected()
 //=======================================================================
 //=======================================================================
 
-USB_ USB;
+USBDevice_ USBDevice;
 
-USB_::USB_()
+USBDevice_::USBDevice_()
 {
 }
 
-void USB_::attach()
+void USBDevice_::attach()
 {
 	_usbConfiguration = 0;
 	UHWCON = 0x01;						// power internal reg
@@ -635,6 +641,12 @@ void USB_::attach()
 	PLLCSR = 0x12;						// Need 16 MHz xtal
 	while (!(PLLCSR & (1<<PLOCK)))		// wait for lock pll
 		;
+
+	// Some tests on specific versions of macosx (10.7.3), reported some
+	// strange behaviuors when the board is reset using the serial
+	// port touch at 1200 bps. This delay fixes this behaviour.
+	delay(1);
+
 	USBCON = ((1<<USBE)|(1<<OTGPADE));	// start USB clock
 	UDIEN = (1<<EORSTE)|(1<<SOFE);		// Enable interrupts for EOR (End of Reset) and SOF (start of frame)
 	UDCON = 0;							// enable attach resistor
@@ -642,19 +654,19 @@ void USB_::attach()
 	TX_RX_LED_INIT;
 }
 
-void USB_::detach()
+void USBDevice_::detach()
 {
 }
 
 //	Check for interrupts
 //	TODO: VBUS detection
-bool USB_::configured()
+bool USBDevice_::configured()
 {
 	return _usbConfiguration;
 }
 
-void USB_::poll()
+void USBDevice_::poll()
 {
 }
 
-#endif /* if defined(USBCON) */
\ No newline at end of file
+#endif /* if defined(USBCON) */
diff --git a/cores/arduino/USBDesc.h b/cores/arduino/USBDesc.h
index 549ed9e..900713e 100644
--- a/cores/arduino/USBDesc.h
+++ b/cores/arduino/USBDesc.h
@@ -60,8 +60,4 @@
 
 #define IMANUFACTURER	1
 #define IPRODUCT		2
-#define USB_PID_LEONARDO 0x0034
-#define USB_PID_MICRO 0x0035
-#define USB_VID 0x2341	// arduino LLC vid
-#define USB_PID	ARDUINO_MODEL_USB_PID	
 
diff --git a/cores/arduino/WInterrupts.c b/cores/arduino/WInterrupts.c
index 3b9fe08..8f3ec84 100755..100644
--- a/cores/arduino/WInterrupts.c
+++ b/cores/arduino/WInterrupts.c
@@ -47,7 +47,19 @@ void attachInterrupt(uint8_t interruptNum, void (*userFunc)(void), int mode) {
     // Enable the interrupt.
       
     switch (interruptNum) {
-#if defined(EICRA) && defined(EICRB) && defined(EIMSK)
+#if defined(__AVR_ATmega32U4__)
+	// I hate doing this, but the register assignment differs between the 1280/2560
+	// and the 32U4.  Since avrlib defines registers PCMSK1 and PCMSK2 that aren't 
+	// even present on the 32U4 this is the only way to distinguish between them.
+	case 0:
+		EICRA = (EICRA & ~((1<<ISC00) | (1<<ISC01))) | (mode << ISC00);
+		EIMSK |= (1<<INT0);
+		break;
+	case 1:
+		EICRA = (EICRA & ~((1<<ISC10) | (1<<ISC11))) | (mode << ISC10);
+		EIMSK |= (1<<INT1);
+		break;	
+#elif defined(EICRA) && defined(EICRB) && defined(EIMSK)
     case 2:
       EICRA = (EICRA & ~((1 << ISC00) | (1 << ISC01))) | (mode << ISC00);
       EIMSK |= (1 << INT0);
@@ -80,7 +92,7 @@ void attachInterrupt(uint8_t interruptNum, void (*userFunc)(void), int mode) {
       EICRB = (EICRB & ~((1 << ISC70) | (1 << ISC71))) | (mode << ISC70);
       EIMSK |= (1 << INT7);
       break;
-#else
+#else		
     case 0:
     #if defined(EICRA) && defined(ISC00) && defined(EIMSK)
       EICRA = (EICRA & ~((1 << ISC00) | (1 << ISC01))) | (mode << ISC00);
@@ -134,7 +146,14 @@ void detachInterrupt(uint8_t interruptNum) {
     // to the number of the EIMSK bit to clear, as this isn't true on the 
     // ATmega8.  There, INT0 is 6 and INT1 is 7.)
     switch (interruptNum) {
-#if defined(EICRA) && defined(EICRB) && defined(EIMSK)
+#if defined(__AVR_ATmega32U4__)
+	case 0:
+		EIMSK &= ~(1<<INT0);
+		break;
+	case 1:
+		EIMSK &= ~(1<<INT1);
+		break;		
+#elif defined(EICRA) && defined(EICRB) && defined(EIMSK)
     case 2:
       EIMSK &= ~(1 << INT0);
       break;
@@ -196,7 +215,18 @@ void attachInterruptTwi(void (*userFunc)(void) ) {
 }
 */
 
-#if defined(EICRA) && defined(EICRB)
+#if defined(__AVR_ATmega32U4__)
+SIGNAL(INT0_vect) {
+	if(intFunc[EXTERNAL_INT_0])
+		intFunc[EXTERNAL_INT_0]();
+}
+
+SIGNAL(INT1_vect) {
+	if(intFunc[EXTERNAL_INT_1])
+		intFunc[EXTERNAL_INT_1]();
+}
+
+#elif defined(EICRA) && defined(EICRB)
 
 SIGNAL(INT0_vect) {
   if(intFunc[EXTERNAL_INT_2])
diff --git a/cores/arduino/main.cpp b/cores/arduino/main.cpp
index 34450f4..3d4e079 100755..100644
--- a/cores/arduino/main.cpp
+++ b/cores/arduino/main.cpp
@@ -5,7 +5,7 @@ int main(void)
 	init();
 
 #if defined(USBCON)
-	USB.attach();
+	USBDevice.attach();
 #endif
 	
 	setup();
diff --git a/cores/arduino/wiring.c b/cores/arduino/wiring.c
index e7f7cde..ac8bb6f 100755..100644
--- a/cores/arduino/wiring.c
+++ b/cores/arduino/wiring.c
@@ -278,12 +278,21 @@ void init()
 	sbi(TCCR3B, CS30);
 	sbi(TCCR3A, WGM30);		// put timer 3 in 8-bit phase correct pwm mode
 #endif
-	
+
+#if defined(TCCR4A) && defined(TCCR4B) && defined(TCCR4D) /* beginning of timer4 block for 32U4 and similar */
+	sbi(TCCR4B, CS42);		// set timer4 prescale factor to 64
+	sbi(TCCR4B, CS41);
+	sbi(TCCR4B, CS40);
+	sbi(TCCR4D, WGM40);		// put timer 4 in phase- and frequency-correct PWM mode	
+	sbi(TCCR4A, PWM4A);		// enable PWM mode for comparator OCR4A
+	sbi(TCCR4C, PWM4D);		// enable PWM mode for comparator OCR4D
+#else /* beginning of timer4 block for ATMEGA1280 and ATMEGA2560 */
 #if defined(TCCR4B) && defined(CS41) && defined(WGM40)
 	sbi(TCCR4B, CS41);		// set timer 4 prescale factor to 64
 	sbi(TCCR4B, CS40);
 	sbi(TCCR4A, WGM40);		// put timer 4 in 8-bit phase correct pwm mode
 #endif
+#endif /* end timer4 block for ATMEGA1280/2560 and similar */	
 
 #if defined(TCCR5B) && defined(CS51) && defined(WGM50)
 	sbi(TCCR5B, CS51);		// set timer 5 prescale factor to 64
diff --git a/cores/arduino/wiring_analog.c b/cores/arduino/wiring_analog.c
index a8bc817..0e9881f 100644
--- a/cores/arduino/wiring_analog.c
+++ b/cores/arduino/wiring_analog.c
@@ -206,14 +206,17 @@ void analogWrite(uint8_t pin, int val)
 				break;
 			#endif
 
-			#if defined(TCCR4A) && defined(COM4A1)
+			#if defined(TCCR4A)
 			case TIMER4A:
-				// connect pwm to pin on timer 4, channel A
+				//connect pwm to pin on timer 4, channel A
 				sbi(TCCR4A, COM4A1);
-				OCR4A = val; // set pwm duty
+				#if defined(COM4A0)		// only used on 32U4
+				cbi(TCCR4A, COM4A0);
+				#endif
+				OCR4A = val;	// set pwm duty
 				break;
 			#endif
-
+			
 			#if defined(TCCR4A) && defined(COM4B1)
 			case TIMER4B:
 				// connect pwm to pin on timer 4, channel B
@@ -230,14 +233,18 @@ void analogWrite(uint8_t pin, int val)
 				break;
 			#endif
 				
-			#if defined(TCCR4A) && defined(COM4D1)
-			case TIMER4D:
+			#if defined(TCCR4C) && defined(COM4D1)
+			case TIMER4D:				
 				// connect pwm to pin on timer 4, channel D
-				sbi(TCCR4A, COM4D1);
-				OCR4D = val; // set pwm duty
+				sbi(TCCR4C, COM4D1);
+				#if defined(COM4D0)		// only used on 32U4
+				cbi(TCCR4C, COM4D0);
+				#endif
+				OCR4D = val;	// set pwm duty
 				break;
 			#endif
 
+							
 			#if defined(TCCR5A) && defined(COM5A1)
 			case TIMER5A:
 				// connect pwm to pin on timer 5, channel A
@@ -272,3 +279,4 @@ void analogWrite(uint8_t pin, int val)
 		}
 	}
 }
+
diff --git a/cores/arduino/wiring_digital.c b/cores/arduino/wiring_digital.c
index 584a28a..be323b1 100755..100644
--- a/cores/arduino/wiring_digital.c
+++ b/cores/arduino/wiring_digital.c
@@ -115,13 +115,17 @@ static void turnOffPWM(uint8_t timer)
 
 		#if defined(TCCR4A) && defined(COM4A1)
 		case  TIMER4A:  cbi(TCCR4A, COM4A1);    break;
-		#endif
+		#endif					
 		#if defined(TCCR4A) && defined(COM4B1)
 		case  TIMER4B:  cbi(TCCR4A, COM4B1);    break;
 		#endif
 		#if defined(TCCR4A) && defined(COM4C1)
 		case  TIMER4C:  cbi(TCCR4A, COM4C1);    break;
-		#endif
+		#endif			
+		#if defined(TCCR4C) && defined(COM4D1)
+		case TIMER4D:	cbi(TCCR4C, COM4D1);	break;
+		#endif			
+			
 		#if defined(TCCR5A)
 		case  TIMER5A:  cbi(TCCR5A, COM5A1);    break;
 		case  TIMER5B:  cbi(TCCR5A, COM5B1);    break;