29 files changed, 497 insertions, 93 deletions
diff --git a/boards.txt b/boards.txt
index 77a062e..b72374d 100644
--- a/boards.txt
+++ b/boards.txt
@@ -144,15 +144,30 @@ nano.menu.cpu.atmega328=ATmega328P
 
 nano.menu.cpu.atmega328.upload.maximum_size=30720
 nano.menu.cpu.atmega328.upload.maximum_data_size=2048
-nano.menu.cpu.atmega328.upload.speed=57600
+nano.menu.cpu.atmega328.upload.speed=115200
 
 nano.menu.cpu.atmega328.bootloader.low_fuses=0xFF
 nano.menu.cpu.atmega328.bootloader.high_fuses=0xDA
 nano.menu.cpu.atmega328.bootloader.extended_fuses=0xFD
-nano.menu.cpu.atmega328.bootloader.file=atmega/ATmegaBOOT_168_atmega328.hex
+nano.menu.cpu.atmega328.bootloader.file=optiboot/optiboot_atmega328.hex
 
 nano.menu.cpu.atmega328.build.mcu=atmega328p
 
+## Arduino Nano w/ ATmega328P (old bootloader)
+## --------------------------
+nano.menu.cpu.atmega328old=ATmega328P (Old Bootloader)
+
+nano.menu.cpu.atmega328old.upload.maximum_size=30720
+nano.menu.cpu.atmega328old.upload.maximum_data_size=2048
+nano.menu.cpu.atmega328old.upload.speed=57600
+
+nano.menu.cpu.atmega328old.bootloader.low_fuses=0xFF
+nano.menu.cpu.atmega328old.bootloader.high_fuses=0xDA
+nano.menu.cpu.atmega328old.bootloader.extended_fuses=0xFD
+nano.menu.cpu.atmega328old.bootloader.file=atmega/ATmegaBOOT_168_atmega328.hex
+
+nano.menu.cpu.atmega328old.build.mcu=atmega328p
+
 ## Arduino Nano w/ ATmega168
 ## -------------------------
 nano.menu.cpu.atmega168=ATmega168
@@ -931,7 +946,7 @@ yunmini.bootloader.tool=avrdude
 yunmini.bootloader.low_fuses=0xff
 yunmini.bootloader.high_fuses=0xd8
 yunmini.bootloader.extended_fuses=0xfb
-yunmini.bootloader.file=caterina/Caterina-Yunmini.hex
+yunmini.bootloader.file=caterina/Caterina-YunMini.hex
 yunmini.bootloader.unlock_bits=0x3F
 yunmini.bootloader.lock_bits=0x2F
 
diff --git a/cores/arduino/Arduino.h b/cores/arduino/Arduino.h
index 09c1448..91eeb16 100644
--- a/cores/arduino/Arduino.h
+++ b/cores/arduino/Arduino.h
@@ -111,7 +111,8 @@ void yield(void);
 #define bitRead(value, bit) (((value) >> (bit)) & 0x01)
 #define bitSet(value, bit) ((value) |= (1UL << (bit)))
 #define bitClear(value, bit) ((value) &= ~(1UL << (bit)))
-#define bitWrite(value, bit, bitvalue) (bitvalue ? bitSet(value, bit) : bitClear(value, bit))
+#define bitToggle(value, bit) ((value) ^= (1UL << (bit)))
+#define bitWrite(value, bit, bitvalue) ((bitvalue) ? bitSet(value, bit) : bitClear(value, bit))
 
 // avr-libc defines _NOP() since 1.6.2
 #ifndef _NOP
@@ -130,16 +131,16 @@ void initVariant(void);
 
 int atexit(void (*func)()) __attribute__((weak));
 
-void pinMode(uint8_t, uint8_t);
-void digitalWrite(uint8_t, uint8_t);
-int digitalRead(uint8_t);
-int analogRead(uint8_t);
+void pinMode(uint8_t pin, uint8_t mode);
+void digitalWrite(uint8_t pin, uint8_t val);
+int digitalRead(uint8_t pin);
+int analogRead(uint8_t pin);
 void analogReference(uint8_t mode);
-void analogWrite(uint8_t, int);
+void analogWrite(uint8_t pin, int val);
 
 unsigned long millis(void);
 unsigned long micros(void);
-void delay(unsigned long);
+void delay(unsigned long ms);
 void delayMicroseconds(unsigned int us);
 unsigned long pulseIn(uint8_t pin, uint8_t state, unsigned long timeout);
 unsigned long pulseInLong(uint8_t pin, uint8_t state, unsigned long timeout);
@@ -147,8 +148,8 @@ unsigned long pulseInLong(uint8_t pin, uint8_t state, unsigned long timeout);
 void shiftOut(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder, uint8_t val);
 uint8_t shiftIn(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder);
 
-void attachInterrupt(uint8_t, void (*)(void), int mode);
-void detachInterrupt(uint8_t);
+void attachInterrupt(uint8_t interruptNum, void (*userFunc)(void), int mode);
+void detachInterrupt(uint8_t interruptNum);
 
 void setup(void);
 void loop(void);
diff --git a/cores/arduino/CDC.cpp b/cores/arduino/CDC.cpp
index 0a743e1..4ff6b9b 100644
--- a/cores/arduino/CDC.cpp
+++ b/cores/arduino/CDC.cpp
@@ -34,14 +34,14 @@ typedef struct
 static volatile LineInfo _usbLineInfo = { 57600, 0x00, 0x00, 0x00, 0x00 };
 static volatile int32_t breakValue = -1;
 
-bool _updatedLUFAbootloader = false;
+static u8 wdtcsr_save;
 
 #define WEAK __attribute__ ((weak))
 
 extern const CDCDescriptor _cdcInterface PROGMEM;
 const CDCDescriptor _cdcInterface =
 {
-	D_IAD(0,2,CDC_COMMUNICATION_INTERFACE_CLASS,CDC_ABSTRACT_CONTROL_MODEL,1),
+	D_IAD(0,2,CDC_COMMUNICATION_INTERFACE_CLASS,CDC_ABSTRACT_CONTROL_MODEL,0),
 
 	//	CDC communication interface
 	D_INTERFACE(CDC_ACM_INTERFACE,1,CDC_COMMUNICATION_INTERFACE_CLASS,CDC_ABSTRACT_CONTROL_MODEL,0),
@@ -57,6 +57,11 @@ const CDCDescriptor _cdcInterface =
 	D_ENDPOINT(USB_ENDPOINT_IN (CDC_ENDPOINT_IN ),USB_ENDPOINT_TYPE_BULK,USB_EP_SIZE,0)
 };
 
+bool isLUFAbootloader()
+{
+	return pgm_read_word(FLASHEND - 1) == NEW_LUFA_SIGNATURE;
+}
+
 int CDC_GetInterface(u8* interfaceNum)
 {
 	interfaceNum[0] += 2;	// uses 2
@@ -92,10 +97,7 @@ bool CDC_Setup(USBSetup& setup)
 		if (CDC_SET_CONTROL_LINE_STATE == r)
 		{
 			_usbLineInfo.lineState = setup.wValueL;
-		}
 
-		if (CDC_SET_LINE_CODING == r || CDC_SET_CONTROL_LINE_STATE == r)
-		{
 			// 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
@@ -109,7 +111,7 @@ bool CDC_Setup(USBSetup& setup)
 #if MAGIC_KEY_POS != (RAMEND-1)
 			// For future boards save the key in the inproblematic RAMEND
 			// Which is reserved for the main() return value (which will never return)
-			if (_updatedLUFAbootloader) {
+			if (isLUFAbootloader()) {
 				// horray, we got a new bootloader!
 				magic_key_pos = (RAMEND-1);
 			}
@@ -119,25 +121,31 @@ bool CDC_Setup(USBSetup& setup)
 			if (1200 == _usbLineInfo.dwDTERate && (_usbLineInfo.lineState & 0x01) == 0)
 			{
 #if MAGIC_KEY_POS != (RAMEND-1)
-				// Backup ram value if its not a newer bootloader.
+				// Backup ram value if its not a newer bootloader and it hasn't already been saved.
 				// This should avoid memory corruption at least a bit, not fully
-				if (magic_key_pos != (RAMEND-1)) {
+				if (magic_key_pos != (RAMEND-1) && *(uint16_t *)magic_key_pos != MAGIC_KEY) {
 					*(uint16_t *)(RAMEND-1) = *(uint16_t *)magic_key_pos;
 				}
 #endif
 				// Store boot key
 				*(uint16_t *)magic_key_pos = MAGIC_KEY;
+				// Save the watchdog state in case the reset is aborted.
+				wdtcsr_save = WDTCSR;
 				wdt_enable(WDTO_120MS);
 			}
-			else
+			else if (*(uint16_t *)magic_key_pos == MAGIC_KEY)
 			{
 				// 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
+				// To avoid spurious resets we set the watchdog to 120ms and eventually
 				// cancel if DTR goes back high.
+				// Cancellation is only done if an auto-reset was started, which is
+				// indicated by the magic key having been set.
 
-				wdt_disable();
 				wdt_reset();
+				// Restore the watchdog state in case the sketch was using it.
+				WDTCSR |= (1<<WDCE) | (1<<WDE);
+				WDTCSR = wdtcsr_save;
 #if MAGIC_KEY_POS != (RAMEND-1)
 				// Restore backed up (old bootloader) magic key data
 				if (magic_key_pos != (RAMEND-1)) {
diff --git a/cores/arduino/HardwareSerial.cpp b/cores/arduino/HardwareSerial.cpp
index 5cd89e5..e99d503 100644
--- a/cores/arduino/HardwareSerial.cpp
+++ b/cores/arduino/HardwareSerial.cpp
@@ -26,6 +26,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <inttypes.h>
+#include <util/atomic.h>
 #include "Arduino.h"
 
 #include "HardwareSerial.h"
@@ -76,6 +77,13 @@ void serialEventRun(void)
 #endif
 }
 
+// macro to guard critical sections when needed for large TX buffer sizes
+#if (SERIAL_TX_BUFFER_SIZE>256)
+#define TX_BUFFER_ATOMIC ATOMIC_BLOCK(ATOMIC_RESTORESTATE)
+#else
+#define TX_BUFFER_ATOMIC
+#endif
+
 // Actual interrupt handlers //////////////////////////////////////////////////////////////
 
 void HardwareSerial::_tx_udr_empty_irq(void)
@@ -89,8 +97,14 @@ void HardwareSerial::_tx_udr_empty_irq(void)
 
   // clear the TXC bit -- "can be cleared by writing a one to its bit
   // location". This makes sure flush() won't return until the bytes
-  // actually got written
-  sbi(*_ucsra, TXC0);
+  // actually got written. Other r/w bits are preserved, and zeroes
+  // written to the rest.
+
+#ifdef MPCM0
+  *_ucsra = ((*_ucsra) & ((1 << U2X0) | (1 << MPCM0))) | (1 << TXC0);
+#else
+  *_ucsra = ((*_ucsra) & ((1 << U2X0) | (1 << TXC0)));
+#endif
 
   if (_tx_buffer_head == _tx_buffer_tail) {
     // Buffer empty, so disable interrupts
@@ -177,15 +191,13 @@ int HardwareSerial::read(void)
 
 int HardwareSerial::availableForWrite(void)
 {
-#if (SERIAL_TX_BUFFER_SIZE>256)
-  uint8_t oldSREG = SREG;
-  cli();
-#endif
-  tx_buffer_index_t head = _tx_buffer_head;
-  tx_buffer_index_t tail = _tx_buffer_tail;
-#if (SERIAL_TX_BUFFER_SIZE>256)
-  SREG = oldSREG;
-#endif
+  tx_buffer_index_t head;
+  tx_buffer_index_t tail;
+
+  TX_BUFFER_ATOMIC {
+    head = _tx_buffer_head;
+    tail = _tx_buffer_tail;
+  }
   if (head >= tail) return SERIAL_TX_BUFFER_SIZE - 1 - head + tail;
   return tail - head - 1;
 }
@@ -218,8 +230,22 @@ size_t HardwareSerial::write(uint8_t c)
   // significantly improve the effective datarate at high (>
   // 500kbit/s) bitrates, where interrupt overhead becomes a slowdown.
   if (_tx_buffer_head == _tx_buffer_tail && bit_is_set(*_ucsra, UDRE0)) {
-    *_udr = c;
-    sbi(*_ucsra, TXC0);
+    // If TXC is cleared before writing UDR and the previous byte
+    // completes before writing to UDR, TXC will be set but a byte
+    // is still being transmitted causing flush() to return too soon.
+    // So writing UDR must happen first.
+    // Writing UDR and clearing TC must be done atomically, otherwise
+    // interrupts might delay the TXC clear so the byte written to UDR
+    // is transmitted (setting TXC) before clearing TXC. Then TXC will
+    // be cleared when no bytes are left, causing flush() to hang
+    ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
+      *_udr = c;
+#ifdef MPCM0
+      *_ucsra = ((*_ucsra) & ((1 << U2X0) | (1 << MPCM0))) | (1 << TXC0);
+#else
+      *_ucsra = ((*_ucsra) & ((1 << U2X0) | (1 << TXC0)));
+#endif
+    }
     return 1;
   }
   tx_buffer_index_t i = (_tx_buffer_head + 1) % SERIAL_TX_BUFFER_SIZE;
@@ -240,9 +266,14 @@ size_t HardwareSerial::write(uint8_t c)
   }
 
   _tx_buffer[_tx_buffer_head] = c;
-  _tx_buffer_head = i;
-	
-  sbi(*_ucsrb, UDRIE0);
+
+  // make atomic to prevent execution of ISR between setting the
+  // head pointer and setting the interrupt flag resulting in buffer
+  // retransmission
+  ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
+    _tx_buffer_head = i;
+    sbi(*_ucsrb, UDRIE0);
+  }
   
   return 1;
 }
diff --git a/cores/arduino/Stream.cpp b/cores/arduino/Stream.cpp
index d284631..9eff663 100644
--- a/cores/arduino/Stream.cpp
+++ b/cores/arduino/Stream.cpp
@@ -218,7 +218,6 @@ size_t Stream::readBytes(char *buffer, size_t length)
 
 size_t Stream::readBytesUntil(char terminator, char *buffer, size_t length)
 {
-  if (length < 1) return 0;
   size_t index = 0;
   while (index < length) {
     int c = timedRead();
diff --git a/cores/arduino/USBAPI.h b/cores/arduino/USBAPI.h
index 479ced9..701a14f 100644
--- a/cores/arduino/USBAPI.h
+++ b/cores/arduino/USBAPI.h
@@ -65,6 +65,8 @@ public:
 	void detach();	// Serial port goes down too...
 	void poll();
 	bool wakeupHost(); // returns false, when wakeup cannot be processed
+
+	bool isSuspended();
 };
 extern USBDevice_ USBDevice;
 
diff --git a/cores/arduino/USBCore.cpp b/cores/arduino/USBCore.cpp
index e00fb02..dc6bc38 100644
--- a/cores/arduino/USBCore.cpp
+++ b/cores/arduino/USBCore.cpp
@@ -35,7 +35,6 @@ extern const u16 STRING_LANGUAGE[] PROGMEM;
 extern const u8 STRING_PRODUCT[] PROGMEM;
 extern const u8 STRING_MANUFACTURER[] PROGMEM;
 extern const DeviceDescriptor USB_DeviceDescriptorIAD PROGMEM;
-extern bool _updatedLUFAbootloader;
 
 const u16 STRING_LANGUAGE[2] = {
 	(3<<8) | (2+2),
@@ -497,14 +496,13 @@ bool SendConfiguration(int maxlen)
 static
 bool SendDescriptor(USBSetup& setup)
 {
-	int ret;
 	u8 t = setup.wValueH;
 	if (USB_CONFIGURATION_DESCRIPTOR_TYPE == t)
 		return SendConfiguration(setup.wLength);
 
 	InitControl(setup.wLength);
 #ifdef PLUGGABLE_USB_ENABLED
-	ret = PluggableUSB().getDescriptor(setup);
+	int ret = PluggableUSB().getDescriptor(setup);
 	if (ret != 0) {
 		return (ret > 0 ? true : false);
 	}
@@ -819,12 +817,6 @@ void USBDevice_::attach()
 	UDIEN = (1<<EORSTE) | (1<<SOFE) | (1<<SUSPE);	// Enable interrupts for EOR (End of Reset), SOF (start of frame) and SUSPEND
 	
 	TX_RX_LED_INIT;
-
-#if MAGIC_KEY_POS != (RAMEND-1)
-	if (pgm_read_word(FLASHEND - 1) == NEW_LUFA_SIGNATURE) {
-		_updatedLUFAbootloader = true;
-	}
-#endif
 }
 
 void USBDevice_::detach()
@@ -862,4 +854,10 @@ bool USBDevice_::wakeupHost()
 	return false;
 }
 
+bool USBDevice_::isSuspended()
+{
+	return (_usbSuspendState & (1 << SUSPI));
+}
+
+
 #endif /* if defined(USBCON) */
diff --git a/cores/arduino/USBCore.h b/cores/arduino/USBCore.h
index 5e0c7b3..0c63c2b 100644
--- a/cores/arduino/USBCore.h
+++ b/cores/arduino/USBCore.h
@@ -288,8 +288,7 @@ typedef struct
 // Old Caterina bootloader places the MAGIC key into unsafe RAM locations (it can be rewritten
 // by the running sketch before to actual reboot).
 // Newer bootloaders, recognizable by the LUFA "signature" at the end of the flash, can handle both
-// the usafe and the safe location. Check once (in USBCore.cpp) if the bootloader in new, then set the global
-// _updatedLUFAbootloader variable to true/false and place the magic key consequently
+// the usafe and the safe location.
 #ifndef MAGIC_KEY
 #define MAGIC_KEY 0x7777
 #endif
diff --git a/cores/arduino/WInterrupts.c b/cores/arduino/WInterrupts.c
index cef1106..ac72dda 100644
--- a/cores/arduino/WInterrupts.c
+++ b/cores/arduino/WInterrupts.c
@@ -65,7 +65,6 @@ static volatile voidFuncPtr intFunc[EXTERNAL_NUM_INTERRUPTS] = {
     nothing,
 #endif
 };
-// volatile static voidFuncPtr twiIntFunc;
 
 void attachInterrupt(uint8_t interruptNum, void (*userFunc)(void), int mode) {
   if(interruptNum < EXTERNAL_NUM_INTERRUPTS) {
@@ -274,11 +273,6 @@ void detachInterrupt(uint8_t interruptNum) {
   }
 }
 
-/*
-void attachInterruptTwi(void (*userFunc)(void) ) {
-  twiIntFunc = userFunc;
-}
-*/
 
 #define IMPLEMENT_ISR(vect, interrupt) \
   ISR(vect) { \
@@ -314,11 +308,3 @@ IMPLEMENT_ISR(INT2_vect, EXTERNAL_INT_2)
 #endif
 
 #endif
-
-/*
-ISR(TWI_vect) {
-  if(twiIntFunc)
-    twiIntFunc();
-}
-*/
-
diff --git a/cores/arduino/WString.cpp b/cores/arduino/WString.cpp
index f2572d6..043fda7 100644
--- a/cores/arduino/WString.cpp
+++ b/cores/arduino/WString.cpp
@@ -121,7 +121,7 @@ String::String(double value, unsigned char decimalPlaces)
 
 String::~String()
 {
-	free(buffer);
+	if (buffer) free(buffer);
 }
 
 /*********************************************/
diff --git a/cores/arduino/new.cpp b/cores/arduino/new.cpp
index cf6f89c..fc30cf8 100644
--- a/cores/arduino/new.cpp
+++ b/cores/arduino/new.cpp
@@ -26,6 +26,11 @@ void *operator new[](size_t size) {
   return malloc(size);
 }
 
+void * operator new(size_t size, void * ptr) noexcept {
+  (void)size;
+  return ptr;
+}
+
 void operator delete(void * ptr) {
   free(ptr);
 }
diff --git a/cores/arduino/new.h b/cores/arduino/new.h
index 6e1b68f..763f5cc 100644
--- a/cores/arduino/new.h
+++ b/cores/arduino/new.h
@@ -23,6 +23,7 @@
 
 void * operator new(size_t size);
 void * operator new[](size_t size);
+void * operator new(size_t size, void * ptr) noexcept;
 void operator delete(void * ptr);
 void operator delete[](void * ptr);
 
diff --git a/cores/arduino/wiring.c b/cores/arduino/wiring.c
index b956f78..9727135 100644
--- a/cores/arduino/wiring.c
+++ b/cores/arduino/wiring.c
@@ -39,7 +39,7 @@ volatile unsigned long timer0_overflow_count = 0;
 volatile unsigned long timer0_millis = 0;
 static unsigned char timer0_fract = 0;
 
-#if defined(__AVR_ATtiny24__) || defined(__AVR_ATtiny44__) || defined(__AVR_ATtiny84__)
+#if defined(TIM0_OVF_vect)
 ISR(TIM0_OVF_vect)
 #else
 ISR(TIMER0_OVF_vect)
diff --git a/cores/arduino/wiring_shift.c b/cores/arduino/wiring_shift.c
index 2b6f7a8..a9b3be5 100644
--- a/cores/arduino/wiring_shift.c
+++ b/cores/arduino/wiring_shift.c
@@ -42,10 +42,13 @@ void shiftOut(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder, uint8_t val)
 	uint8_t i;
 
 	for (i = 0; i < 8; i++)  {
-		if (bitOrder == LSBFIRST)
-			digitalWrite(dataPin, !!(val & (1 << i)));
-		else	
-			digitalWrite(dataPin, !!(val & (1 << (7 - i))));
+		if (bitOrder == LSBFIRST) {
+			digitalWrite(dataPin, val & 1);
+			val >>= 1;
+		} else {	
+			digitalWrite(dataPin, (val & 128) != 0);
+			val <<= 1;
+		}
 			
 		digitalWrite(clockPin, HIGH);
 		digitalWrite(clockPin, LOW);		
diff --git a/extras/pack.hourlybuild.bash b/extras/pack.hourlybuild.bash
new file mode 100755
index 0000000..b3a269f
--- /dev/null
+++ b/extras/pack.hourlybuild.bash
@@ -0,0 +1,51 @@
+#!/bin/bash -ex
+
+#  pack.*.bash - Bash script to help packaging avr core releases.
+#  Copyright (c) 2015 Arduino LLC.  All right reserved.
+#
+#  This library is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2.1 of the License, or (at your option) any later version.
+#
+#  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.  See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library; if not, write to the Free Software
+#  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+BUILD_NUMBER=$1
+CURR_TIME=`date "+%Y-%m-%d %H:%M"`
+CURR_TIME_SED=`date "+%Y\\-%m\\-%d %H:%M"`
+VERSION=9.9.9-Hourly
+
+PWD=`pwd`
+FOLDERNAME=`basename $PWD`
+THIS_SCRIPT_NAME=`basename $0`
+FILENAME=package_avr-hourly-b${BUILD_NUMBER}.tar.bz2
+
+rm -f $FILENAME
+
+# Change name in platform.txt
+sed -i "s/name=.*/name=SAMD Hourly Build ${BUILD_NUMBER} (${CURR_TIME})/" platform.txt
+
+cd ..
+tar --transform "s|$FOLDERNAME|avr-hourly_b${BUILD_NUMBER}|g"  --exclude=extras/** --exclude=.git* --exclude=.idea -cjf $FILENAME $FOLDERNAME
+cd -
+
+mv ../$FILENAME .
+
+CHKSUM=`sha256sum $FILENAME | awk '{ print $1 }'`
+SIZE=`wc -c $FILENAME | awk '{ print $1 }'`
+
+cat extras/package_index.json.Hourly.template |
+sed "s/%%BUILD_NUMBER%%/${BUILD_NUMBER}/" |
+sed "s/%%CURR_TIME%%/${CURR_TIME_SED}/" |
+sed "s/%%VERSION%%/${VERSION}/" |
+sed "s/%%FILENAME%%/${FILENAME}/" |
+sed "s/%%CHECKSUM%%/${CHKSUM}/" |
+sed "s/%%SIZE%%/${SIZE}/" > package_avr-hourly-build_index.json
+
diff --git a/extras/pack.pullrequest.bash b/extras/pack.pullrequest.bash
new file mode 100755
index 0000000..64f5b95
--- /dev/null
+++ b/extras/pack.pullrequest.bash
@@ -0,0 +1,50 @@
+#!/bin/bash -ex
+
+#  pack.*.bash - Bash script to help packaging avr core releases.
+#  Copyright (c) 2015 Arduino LLC.  All right reserved.
+#
+#  This library is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2.1 of the License, or (at your option) any later version.
+#
+#  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.  See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library; if not, write to the Free Software
+#  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+PR_NUMBER=$1
+BUILD_NUMBER=$2
+VERSION=`grep version= platform.txt | sed 's/version=//g'`
+
+PWD=`pwd`
+FOLDERNAME=`basename $PWD`
+THIS_SCRIPT_NAME=`basename $0`
+FILENAME=package_avr-b${BUILD_NUMBER}.tar.bz2
+
+rm -f $FILENAME
+
+# Change name in platform.txt
+sed -i "s/name=.*/name=SAMD Pull request #${PR_NUMBER} (Build ${BUILD_NUMBER})/" platform.txt
+
+cd ..
+tar --transform "s|$FOLDERNAME|avr-PR${PR_NUMBER}_b${BUILD_NUMBER}|g"  --exclude=extras/** --exclude=.git* --exclude=.idea -cjf $FILENAME $FOLDERNAME
+cd -
+
+mv ../$FILENAME .
+
+CHKSUM=`sha256sum $FILENAME | awk '{ print $1 }'`
+SIZE=`wc -c $FILENAME | awk '{ print $1 }'`
+
+cat extras/package_index.json.PR.template |
+sed s/%%PR_NUMBER%%/${PR_NUMBER}/ |
+sed s/%%BUILD_NUMBER%%/${BUILD_NUMBER}/ |
+sed s/%%VERSION%%/${VERSION}-build-${BUILD_NUMBER}/ |
+sed s/%%FILENAME%%/${FILENAME}/ |
+sed s/%%CHECKSUM%%/${CHKSUM}/ |
+sed s/%%SIZE%%/${SIZE}/ > package_avr-b${BUILD_NUMBER}_index.json
+
diff --git a/extras/pack.release.bash b/extras/pack.release.bash
new file mode 100755
index 0000000..a2999d5
--- /dev/null
+++ b/extras/pack.release.bash
@@ -0,0 +1,33 @@
+#!/bin/bash -ex
+
+#  pack.*.bash - Bash script to help packaging avr core releases.
+#  Copyright (c) 2015 Arduino LLC.  All right reserved.
+#
+#  This library is free software; you can redistribute it and/or
+#  modify it under the terms of the GNU Lesser General Public
+#  License as published by the Free Software Foundation; either
+#  version 2.1 of the License, or (at your option) any later version.
+#
+#  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.  See the GNU
+#  Lesser General Public License for more details.
+#
+#  You should have received a copy of the GNU Lesser General Public
+#  License along with this library; if not, write to the Free Software
+#  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+VERSION=`grep version= platform.txt | sed 's/version=//g'`
+
+PWD=`pwd`
+FOLDERNAME=`basename $PWD`
+THIS_SCRIPT_NAME=`basename $0`
+
+rm -f avr-$VERSION.tar.bz2
+
+cd ..
+tar --transform "s|$FOLDERNAME|$FOLDERNAME-$VERSION|g"  --exclude=extras/** --exclude=.git* --exclude=.idea -cjf avr-$VERSION.tar.bz2 $FOLDERNAME
+cd -
+
+mv ../avr-$VERSION.tar.bz2 .
+
diff --git a/extras/package_index.json.Hourly.template b/extras/package_index.json.Hourly.template
new file mode 100644
index 0000000..49c71dd
--- /dev/null
+++ b/extras/package_index.json.Hourly.template
@@ -0,0 +1,72 @@
+{
+  "packages": [
+    {
+      "name": "arduino-beta",
+      "maintainer": "Arduino Betatesting",
+      "websiteURL": "http://www.arduino.cc/",
+      "email": "packages@arduino.cc",
+      "help": {
+        "online": "http://www.arduino.cc/en/Reference/HomePage"
+      },
+      "platforms": [
+        {
+          "name": "Arduino AVR core - Hourly build",
+          "architecture": "avr",
+          "version": "%%VERSION%%",
+          "category": "Arduino",
+          "url": "http://downloads.arduino.cc/Hourly/avr/%%FILENAME%%",
+          "archiveFileName": "%%FILENAME%%",
+          "checksum": "SHA-256:%%CHECKSUM%%",
+          "size": "%%SIZE%%",
+          "boards": [
+            {"name": "Arduino Yún"},
+            {"name": "Arduino/Genuino Uno"},
+            {"name": "Arduino Uno WiFi"},
+            {"name": "Arduino Diecimila"},
+            {"name": "Arduino Nano"},
+            {"name": "Arduino/Genuino Mega"},
+            {"name": "Arduino MegaADK"},
+            {"name": "Arduino Leonardo"},
+            {"name": "Arduino Leonardo Ethernet"},
+            {"name": "Arduino/Genuino Micro"},
+            {"name": "Arduino Esplora"},
+            {"name": "Arduino Mini"},
+            {"name": "Arduino Ethernet"},
+            {"name": "Arduino Fio"},
+            {"name": "Arduino BT"},
+            {"name": "Arduino LilyPadUSB"},
+            {"name": "Arduino Lilypad"},
+            {"name": "Arduino Pro"},
+            {"name": "Arduino ATMegaNG"},
+            {"name": "Arduino Robot Control"},
+            {"name": "Arduino Robot Motor"},
+            {"name": "Arduino Gemma"},
+            {"name": "Adafruit Circuit Playground"},
+            {"name": "Arduino Yún Mini"},
+            {"name": "Arduino Industrial 101"},
+            {"name": "Linino One"}
+          ],
+          "toolsDependencies": [
+            {
+              "packager": "arduino",
+              "name": "avr-gcc",
+              "version": "4.9.2-atmel3.5.4-arduino2"
+            },
+            {
+              "packager": "arduino",
+              "name": "avrdude",
+              "version": "6.3.0-arduino9"
+            },
+            {
+              "packager": "arduino",
+              "name": "arduinoOTA",
+              "version": "1.1.1"
+            }
+          ]
+        }
+      ],
+      "tools": [
+      ]
+    }
+  ]
+}
diff --git a/extras/package_index.json.PR.template b/extras/package_index.json.PR.template
new file mode 100644
index 0000000..17cfa50
--- /dev/null
+++ b/extras/package_index.json.PR.template
@@ -0,0 +1,72 @@
+{
+  "packages": [
+    {
+      "name": "arduino-beta",
+      "maintainer": "Arduino Betatesting",
+      "websiteURL": "http://www.arduino.cc/",
+      "email": "packages@arduino.cc",
+      "help": {
+        "online": "http://www.arduino.cc/en/Reference/HomePage"
+      },
+      "platforms": [
+        {
+          "name": "Arduino AVR core - Pull request #%%PR_NUMBER%% (build %%BUILD_NUMBER%%)",
+          "architecture": "avr",
+          "version": "%%VERSION%%",
+          "category": "Arduino",
+          "url": "http://downloads.arduino.cc/PR/a/%%FILENAME%%",
+          "archiveFileName": "%%FILENAME%%",
+          "checksum": "SHA-256:%%CHECKSUM%%",
+          "size": "%%SIZE%%",
+          "boards": [
+            {"name": "Arduino Yún"},
+            {"name": "Arduino/Genuino Uno"},
+            {"name": "Arduino Uno WiFi"},
+            {"name": "Arduino Diecimila"},
+            {"name": "Arduino Nano"},
+            {"name": "Arduino/Genuino Mega"},
+            {"name": "Arduino MegaADK"},
+            {"name": "Arduino Leonardo"},
+            {"name": "Arduino Leonardo Ethernet"},
+            {"name": "Arduino/Genuino Micro"},
+            {"name": "Arduino Esplora"},
+            {"name": "Arduino Mini"},
+            {"name": "Arduino Ethernet"},
+            {"name": "Arduino Fio"},
+            {"name": "Arduino BT"},
+            {"name": "Arduino LilyPadUSB"},
+            {"name": "Arduino Lilypad"},
+            {"name": "Arduino Pro"},
+            {"name": "Arduino ATMegaNG"},
+            {"name": "Arduino Robot Control"},
+            {"name": "Arduino Robot Motor"},
+            {"name": "Arduino Gemma"},
+            {"name": "Adafruit Circuit Playground"},
+            {"name": "Arduino Yún Mini"},
+            {"name": "Arduino Industrial 101"},
+            {"name": "Linino One"}
+          ],
+          "toolsDependencies": [
+            {
+              "packager": "arduino",
+              "name": "avr-gcc",
+              "version": "4.9.2-atmel3.5.4-arduino2"
+            },
+            {
+              "packager": "arduino",
+              "name": "avrdude",
+              "version": "6.3.0-arduino9"
+            },
+            {
+              "packager": "arduino",
+              "name": "arduinoOTA",
+              "version": "1.1.1"
+            }
+          ]
+        }
+      ],
+      "tools": [
+      ]
+    }
+  ]
+}
diff --git a/libraries/EEPROM/src/EEPROM.h b/libraries/EEPROM/src/EEPROM.h
index cde75db..c8ec271 100644
--- a/libraries/EEPROM/src/EEPROM.h
+++ b/libraries/EEPROM/src/EEPROM.h
@@ -40,7 +40,7 @@ struct EERef{
     
     //Access/read members.
     uint8_t operator*() const            { return eeprom_read_byte( (uint8_t*) index ); }
-    operator const uint8_t() const       { return **this; }
+    operator uint8_t() const             { return **this; }
     
     //Assignment/write members.
     EERef &operator=( const EERef &ref ) { return *this = *ref; }
@@ -89,7 +89,7 @@ struct EEPtr{
     EEPtr( const int index )
         : index( index )                {}
         
-    operator const int() const          { return index; }
+    operator int() const                { return index; }
     EEPtr &operator=( int in )          { return index = in, *this; }
     
     //Iterator functionality.
@@ -143,4 +143,4 @@ struct EEPROMClass{
 };
 
 static EEPROMClass EEPROM;
-#endif
-\ No newline at end of file
+#endif
diff --git a/libraries/SPI/examples/DigitalPotControl/DigitalPotControl.ino b/libraries/SPI/examples/DigitalPotControl/DigitalPotControl.ino
index c7afcc0..8719058 100644
--- a/libraries/SPI/examples/DigitalPotControl/DigitalPotControl.ino
+++ b/libraries/SPI/examples/DigitalPotControl/DigitalPotControl.ino
@@ -63,9 +63,11 @@ void loop() {
 void digitalPotWrite(int address, int value) {
   // take the SS pin low to select the chip:
   digitalWrite(slaveSelectPin, LOW);
+  delay(100);
   //  send in the address and value via SPI:
   SPI.transfer(address);
   SPI.transfer(value);
+  delay(100);
   // take the SS pin high to de-select the chip:
   digitalWrite(slaveSelectPin, HIGH);
 }
diff --git a/libraries/SoftwareSerial/src/SoftwareSerial.cpp b/libraries/SoftwareSerial/src/SoftwareSerial.cpp
index 474fe4a..3163d7a 100644
--- a/libraries/SoftwareSerial/src/SoftwareSerial.cpp
+++ b/libraries/SoftwareSerial/src/SoftwareSerial.cpp
@@ -316,7 +316,7 @@ void SoftwareSerial::begin(long speed)
   _tx_delay = subtract_cap(bit_delay, 15 / 4);
 
   // Only setup rx when we have a valid PCINT for this pin
-  if (digitalPinToPCICR(_receivePin)) {
+  if (digitalPinToPCICR((int8_t)_receivePin)) {
     #if GCC_VERSION > 40800
     // Timings counted from gcc 4.8.2 output. This works up to 115200 on
     // 16Mhz and 57600 on 8Mhz.
@@ -357,7 +357,7 @@ void SoftwareSerial::begin(long speed)
     // Enable the PCINT for the entire port here, but never disable it
     // (others might also need it, so we disable the interrupt by using
     // the per-pin PCMSK register).
-    *digitalPinToPCICR(_receivePin) |= _BV(digitalPinToPCICRbit(_receivePin));
+    *digitalPinToPCICR((int8_t)_receivePin) |= _BV(digitalPinToPCICRbit(_receivePin));
     // Precalculate the pcint mask register and value, so setRxIntMask
     // can be used inside the ISR without costing too much time.
     _pcint_maskreg = digitalPinToPCMSK(_receivePin);
diff --git a/libraries/SoftwareSerial/src/SoftwareSerial.h b/libraries/SoftwareSerial/src/SoftwareSerial.h
index b1a37c4..d8b88ce 100644
--- a/libraries/SoftwareSerial/src/SoftwareSerial.h
+++ b/libraries/SoftwareSerial/src/SoftwareSerial.h
@@ -111,13 +111,4 @@ public:
   static inline void handle_interrupt() __attribute__((__always_inline__));
 };
 
-// Arduino 0012 workaround
-#undef int
-#undef char
-#undef long
-#undef byte
-#undef float
-#undef abs
-#undef round
-
 #endif
diff --git a/libraries/Wire/examples/digital_potentiometer/digital_potentiometer.ino b/libraries/Wire/examples/digital_potentiometer/digital_potentiometer.ino
index 5fb91fb..dd40a25 100644
--- a/libraries/Wire/examples/digital_potentiometer/digital_potentiometer.ino
+++ b/libraries/Wire/examples/digital_potentiometer/digital_potentiometer.ino
@@ -9,8 +9,6 @@
 
 // This example code is in the public domain.
 
-// This example code is in the public domain.
-
 
 #include <Wire.h>
 
diff --git a/libraries/Wire/examples/i2c_scanner/i2c_scanner.ino b/libraries/Wire/examples/i2c_scanner/i2c_scanner.ino
new file mode 100644
index 0000000..3febbf4
--- /dev/null
+++ b/libraries/Wire/examples/i2c_scanner/i2c_scanner.ino
@@ -0,0 +1,75 @@
+// --------------------------------------
+// i2c_scanner
+//
+// Version 1
+//    This program (or code that looks like it)
+//    can be found in many places.
+//    For example on the Arduino.cc forum.
+//    The original author is not know.
+// Version 2, Juni 2012, Using Arduino 1.0.1
+//     Adapted to be as simple as possible by Arduino.cc user Krodal
+// Version 3, Feb 26  2013
+//    V3 by louarnold
+// Version 4, March 3, 2013, Using Arduino 1.0.3
+//    by Arduino.cc user Krodal.
+//    Changes by louarnold removed.
+//    Scanning addresses changed from 0...127 to 1...119,
+//    according to the i2c scanner by Nick Gammon
+//    https://www.gammon.com.au/forum/?id=10896
+// Version 5, March 28, 2013
+//    As version 4, but address scans now to 127.
+//    A sensor seems to use address 120.
+// Version 6, November 27, 2015.
+//    Added waiting for the Leonardo serial communication.
+//
+//
+// This sketch tests the standard 7-bit addresses
+// Devices with higher bit address might not be seen properly.
+//
+
+#include <Wire.h>
+
+void setup() {
+  Wire.begin();
+
+  Serial.begin(9600);
+  while (!Serial); // Leonardo: wait for serial monitor
+  Serial.println("\nI2C Scanner");
+}
+
+void loop() {
+  int nDevices = 0;
+
+  Serial.println("Scanning...");
+
+  for (byte address = 1; address < 127; ++address) {
+    // The i2c_scanner uses the return value of
+    // the Write.endTransmisstion to see if
+    // a device did acknowledge to the address.
+    Wire.beginTransmission(address);
+    byte error = Wire.endTransmission();
+
+    if (error == 0) {
+      Serial.print("I2C device found at address 0x");
+      if (address < 16) {
+        Serial.print("0");
+      }
+      Serial.print(address, HEX);
+      Serial.println("  !");
+
+      ++nDevices;
+    } else if (error == 4) {
+      Serial.print("Unknown error at address 0x");
+      if (address < 16) {
+        Serial.print("0");
+      }
+      Serial.println(address, HEX);
+    }
+  }
+  if (nDevices == 0) {
+    Serial.println("No I2C devices found\n");
+  } else {
+    Serial.println("done\n");
+  }
+  delay(5000); // Wait 5 seconds for next scan
+}
diff --git a/libraries/Wire/src/Wire.cpp b/libraries/Wire/src/Wire.cpp
index d2146f7..58916ce 100644
--- a/libraries/Wire/src/Wire.cpp
+++ b/libraries/Wire/src/Wire.cpp
@@ -17,6 +17,7 @@
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  
   Modified 2012 by Todd Krein (todd@krein.org) to implement repeated starts
+  Modified 2017 by Chuck Todd (ctodd@cableone.net) to correct Unconfigured Slave Mode reboot
 */
 
 extern "C" {
@@ -60,14 +61,14 @@ void TwoWire::begin(void)
   txBufferLength = 0;
 
   twi_init();
+  twi_attachSlaveTxEvent(onRequestService); // default callback must exist
+  twi_attachSlaveRxEvent(onReceiveService); // default callback must exist
 }
 
 void TwoWire::begin(uint8_t address)
 {
-  twi_setAddress(address);
-  twi_attachSlaveTxEvent(onRequestService);
-  twi_attachSlaveRxEvent(onReceiveService);
   begin();
+  twi_setAddress(address);
 }
 
 void TwoWire::begin(int address)
diff --git a/libraries/Wire/src/utility/twi.c b/libraries/Wire/src/utility/twi.c
index 171af73..1a35146 100644
--- a/libraries/Wire/src/utility/twi.c
+++ b/libraries/Wire/src/utility/twi.c
@@ -445,6 +445,7 @@ ISR(TWI_vect)
     case TW_MR_DATA_ACK: // data received, ack sent
       // put byte into buffer
       twi_masterBuffer[twi_masterBufferIndex++] = TWDR;
+      __attribute__ ((fallthrough));
     case TW_MR_SLA_ACK:  // address sent, ack received
       // ack if more bytes are expected, otherwise nack
       if(twi_masterBufferIndex < twi_masterBufferLength){
@@ -530,6 +531,7 @@ ISR(TWI_vect)
         twi_txBufferLength = 1;
         twi_txBuffer[0] = 0x00;
       }
+      __attribute__ ((fallthrough));		  
       // transmit first byte from buffer, fall
     case TW_ST_DATA_ACK: // byte sent, ack returned
       // copy data to output register
diff --git a/platform.txt b/platform.txt
index f7fb447..9d18d7b 100644
--- a/platform.txt
+++ b/platform.txt
@@ -6,7 +6,7 @@
 # https://github.com/arduino/Arduino/wiki/Arduino-IDE-1.5-3rd-party-Hardware-specification
 
 name=Arduino AVR Boards
-version=1.6.20
+version=1.6.23
 
 # AVR compile variables
 # ---------------------
@@ -25,7 +25,7 @@ compiler.c.elf.flags={compiler.warning_flags} -Os -g -flto -fuse-linker-plugin -
 compiler.c.elf.cmd=avr-gcc
 compiler.S.flags=-c -g -x assembler-with-cpp -flto -MMD
 compiler.cpp.cmd=avr-g++
-compiler.cpp.flags=-c -g -Os {compiler.warning_flags} -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -MMD -flto
+compiler.cpp.flags=-c -g -Os {compiler.warning_flags} -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -Wno-error=narrowing -MMD -flto
 compiler.ar.cmd=avr-gcc-ar
 compiler.ar.flags=rcs
 compiler.objcopy.cmd=avr-objcopy
@@ -65,7 +65,7 @@ archive_file_path={build.path}/{archive_file}
 recipe.ar.pattern="{compiler.path}{compiler.ar.cmd}" {compiler.ar.flags} {compiler.ar.extra_flags} "{archive_file_path}" "{object_file}"
 
 ## Combine gc-sections, archives, and objects
-recipe.c.combine.pattern="{compiler.path}{compiler.c.elf.cmd}" {compiler.c.elf.flags} -mmcu={build.mcu} {compiler.c.elf.extra_flags} -o "{build.path}/{build.project_name}.elf" {object_files} "{build.path}/{archive_file}" "-L{build.path}" -lm
+recipe.c.combine.pattern="{compiler.path}{compiler.c.elf.cmd}" {compiler.c.elf.flags} -mmcu={build.mcu} {compiler.c.elf.extra_flags} -o "{build.path}/{build.project_name}.elf" {object_files} {compiler.libraries.ldflags} "{build.path}/{archive_file}" "-L{build.path}" -lm
 
 ## Create output files (.eep and .hex)
 recipe.objcopy.eep.pattern="{compiler.path}{compiler.objcopy.cmd}" {compiler.objcopy.eep.flags} {compiler.objcopy.eep.extra_flags} "{build.path}/{build.project_name}.elf" "{build.path}/{build.project_name}.eep"
diff --git a/programmers.txt b/programmers.txt
index c100e84..69ddf69 100644
--- a/programmers.txt
+++ b/programmers.txt
@@ -50,6 +50,15 @@ arduinoasisp.program.speed=19200
 arduinoasisp.program.tool=avrdude
 arduinoasisp.program.extra_params=-P{serial.port} -b{program.speed}
 
+arduinoasispatmega32u4.name=Arduino as ISP (ATmega32U4)
+arduinoasispatmega32u4.communication=serial
+arduinoasispatmega32u4.protocol=arduino
+arduinoasispatmega32u4.speed=19200
+arduinoasispatmega32u4.program.protocol=arduino
+arduinoasispatmega32u4.program.speed=19200
+arduinoasispatmega32u4.program.tool=avrdude
+arduinoasispatmega32u4.program.extra_params=-P{serial.port} -b{program.speed}
+
 usbGemma.name=Arduino Gemma
 usbGemma.protocol=arduinogemma
 usbGemma.program.tool=avrdude