Merge pull request #14 from dmadison/upstream-1.8.4

Merge upstream tag '1.8.4'

40 files changed, 381 insertions, 149 deletions

diff --git a/.codespellrc b/.codespellrc
new file mode 100644
index 0000000..d5d337d
--- /dev/null
+++ b/.codespellrc
@@ -0,0 +1,8 @@
+# See: https://github.com/codespell-project/codespell#using-a-config-file
+[codespell]
+# In the event of a false positive, add the problematic word, in all lowercase, to a comma-separated list here:
+ignore-words-list = hart,pullrequest
+builtin = clear
+check-filenames =
+check-hidden =
+skip = ./.git,./firmwares/arduinoISP,./firmwares/wifishield,./bootloaders
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a5f6455..9707eca 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -3,7 +3,7 @@ name: build
 on: [push, pull_request, workflow_dispatch]
 
 env:
-  IDE_VERSION: 1.8.13
+  IDE_VERSION: 1.8.19
   IDE_LOCATION: /usr/local/share/arduino
 
 jobs:
diff --git a/README.md b/README.md
index 81d39d0..1be62e6 100644
--- a/README.md
+++ b/README.md
@@ -47,7 +47,7 @@ Lastly, you need to know where the 'reset' button is on your Arduino. If your bo
 To upload to the board:
 * Press the 'Upload' button in the IDE
 * Wait until the status bar says "Uploading..."
-* Press the reset button
+* Press the reset button twice, quickly
 
 If you timed it properly, the board should reset to the bootloader and the upload should begin. AVRDUDE will do its thing and you should see `avrdude done.  Thank you.` near the bottom of the output window.
 
diff --git a/boards.txt b/boards.txt
index a860efb..79fd6f6 100644
--- a/boards.txt
+++ b/boards.txt
@@ -1,4 +1,4 @@
-# See: http://code.google.com/p/arduino/wiki/Platforms
+# See: https://arduino.github.io/arduino-cli/latest/platform-specification/
 
 menu.cpu=Processor
 
@@ -15,8 +15,19 @@ yun.vid.2=0x2A03
 yun.pid.2=0x0041
 yun.vid.3=0x2A03
 yun.pid.3=0x8041
+yun.upload_port.0.vid=0x2341
+yun.upload_port.0.pid=0x0041
+yun.upload_port.1.vid=0x2341
+yun.upload_port.1.pid=0x8041
+yun.upload_port.2.vid=0x2A03
+yun.upload_port.2.pid=0x0041
+yun.upload_port.3.vid=0x2A03
+yun.upload_port.3.pid=0x8041
+yun.upload_port.4.board=yun
 
 yun.upload.tool=avrdude
+yun.upload.tool.default=avrdude
+yun.upload.tool.network=arduino_ota
 yun.upload.protocol=avr109
 yun.upload.maximum_size=28672
 yun.upload.maximum_data_size=2560
@@ -26,6 +37,7 @@ yun.upload.use_1200bps_touch=true
 yun.upload.wait_for_upload_port=true
 
 yun.bootloader.tool=avrdude
+yun.bootloader.tool.default=avrdude
 yun.bootloader.low_fuses=0xff
 yun.bootloader.high_fuses=0xd8
 yun.bootloader.extended_fuses=0xfb
@@ -55,8 +67,19 @@ leonardo.vid.2=0x2A03
 leonardo.pid.2=0x0036
 leonardo.vid.3=0x2A03
 leonardo.pid.3=0x8036
+leonardo.upload_port.0.vid=0x2341
+leonardo.upload_port.0.pid=0x0036
+leonardo.upload_port.1.vid=0x2341
+leonardo.upload_port.1.pid=0x8036
+leonardo.upload_port.2.vid=0x2A03
+leonardo.upload_port.2.pid=0x0036
+leonardo.upload_port.3.vid=0x2A03
+leonardo.upload_port.3.pid=0x8036
+leonardo.upload_port.4.board=leonardo
 
 leonardo.upload.tool=avrdude
+leonardo.upload.tool.default=avrdude
+leonardo.upload.tool.network=arduino_ota
 leonardo.upload.protocol=avr109
 leonardo.upload.maximum_size=28672
 leonardo.upload.maximum_data_size=2560
@@ -66,6 +89,7 @@ leonardo.upload.use_1200bps_touch=true
 leonardo.upload.wait_for_upload_port=true
 
 leonardo.bootloader.tool=avrdude
+leonardo.bootloader.tool.default=avrdude
 leonardo.bootloader.low_fuses=0xff
 leonardo.bootloader.high_fuses=0xd8
 leonardo.bootloader.extended_fuses=0xcb
@@ -90,8 +114,15 @@ leonardoeth.vid.0=0x2a03
 leonardoeth.pid.0=0x0040
 leonardoeth.vid.1=0x2a03
 leonardoeth.pid.1=0x8040
+leonardoeth.upload_port.0.vid=0x2a03
+leonardoeth.upload_port.0.pid=0x0040
+leonardoeth.upload_port.1.vid=0x2a03
+leonardoeth.upload_port.1.pid=0x8040
+leonardoeth.upload_port.2.board=leonardoeth
 
 leonardoeth.upload.tool=avrdude
+leonardoeth.upload.tool.default=avrdude
+leonardoeth.upload.tool.network=arduino_ota
 leonardoeth.upload.protocol=avr109
 leonardoeth.upload.maximum_size=28672
 leonardoeth.upload.maximum_data_size=2560
@@ -101,6 +132,7 @@ leonardoeth.upload.use_1200bps_touch=true
 leonardoeth.upload.wait_for_upload_port=true
 
 leonardoeth.bootloader.tool=avrdude
+leonardoeth.bootloader.tool.default=avrdude
 leonardoeth.bootloader.low_fuses=0xff
 leonardoeth.bootloader.high_fuses=0xd8
 leonardoeth.bootloader.extended_fuses=0xcb
@@ -134,8 +166,23 @@ micro.vid.4=0x2341
 micro.pid.4=0x0237
 micro.vid.5=0x2341
 micro.pid.5=0x8237
+micro.upload_port.0.vid=0x2341
+micro.upload_port.0.pid=0x0037
+micro.upload_port.1.vid=0x2341
+micro.upload_port.1.pid=0x8037
+micro.upload_port.2.vid=0x2A03
+micro.upload_port.2.pid=0x0037
+micro.upload_port.3.vid=0x2A03
+micro.upload_port.3.pid=0x8037
+micro.upload_port.4.vid=0x2341
+micro.upload_port.4.pid=0x0237
+micro.upload_port.5.vid=0x2341
+micro.upload_port.5.pid=0x8237
+micro.upload_port.6.board=micro
 
 micro.upload.tool=avrdude
+micro.upload.tool.default=avrdude
+micro.upload.tool.network=arduino_ota
 micro.upload.protocol=avr109
 micro.upload.maximum_size=28672
 micro.upload.maximum_data_size=2560
@@ -145,6 +192,7 @@ micro.upload.use_1200bps_touch=true
 micro.upload.wait_for_upload_port=true
 
 micro.bootloader.tool=avrdude
+micro.bootloader.tool.default=avrdude
 micro.bootloader.low_fuses=0xff
 micro.bootloader.high_fuses=0xd8
 micro.bootloader.extended_fuses=0xcb
@@ -173,8 +221,19 @@ esplora.vid.2=0x2A03
 esplora.pid.2=0x003C
 esplora.vid.3=0x2A03
 esplora.pid.3=0x803C
+esplora.upload_port.0.vid=0x2341
+esplora.upload_port.0.pid=0x003C
+esplora.upload_port.1.vid=0x2341
+esplora.upload_port.1.pid=0x803C
+esplora.upload_port.2.vid=0x2A03
+esplora.upload_port.2.pid=0x003C
+esplora.upload_port.3.vid=0x2A03
+esplora.upload_port.3.pid=0x803C
+esplora.upload_port.4.board=esplora
 
 esplora.upload.tool=avrdude
+esplora.upload.tool.default=avrdude
+esplora.upload.tool.network=arduino_ota
 esplora.upload.protocol=avr109
 esplora.upload.maximum_size=28672
 esplora.upload.maximum_data_size=2560
@@ -184,6 +243,7 @@ esplora.upload.use_1200bps_touch=true
 esplora.upload.wait_for_upload_port=true
 
 esplora.bootloader.tool=avrdude
+esplora.bootloader.tool.default=avrdude
 esplora.bootloader.low_fuses=0xff
 esplora.bootloader.high_fuses=0xd8
 esplora.bootloader.extended_fuses=0xcb
@@ -208,8 +268,15 @@ LilyPadUSB.vid.0=0x1B4F
 LilyPadUSB.pid.0=0x9207
 LilyPadUSB.vid.1=0x1B4F
 LilyPadUSB.pid.1=0x9208
+LilyPadUSB.upload_port.0.vid=0x1B4F
+LilyPadUSB.upload_port.0.pid=0x9207
+LilyPadUSB.upload_port.1.vid=0x1B4F
+LilyPadUSB.upload_port.1.pid=0x9208
+LilyPadUSB.upload_port.2.board=LilyPadUSB
 
 LilyPadUSB.upload.tool=avrdude
+LilyPadUSB.upload.tool.default=avrdude
+LilyPadUSB.upload.tool.network=arduino_ota
 LilyPadUSB.upload.protocol=avr109
 LilyPadUSB.upload.maximum_size=28672
 LilyPadUSB.upload.maximum_data_size=2560
@@ -219,6 +286,7 @@ LilyPadUSB.upload.use_1200bps_touch=true
 LilyPadUSB.upload.wait_for_upload_port=true
 
 LilyPadUSB.bootloader.tool=avrdude
+LilyPadUSB.bootloader.tool.default=avrdude
 LilyPadUSB.bootloader.low_fuses=0xff
 LilyPadUSB.bootloader.high_fuses=0xd8
 LilyPadUSB.bootloader.extended_fuses=0xce
@@ -247,8 +315,19 @@ robotControl.vid.2=0x2A03
 robotControl.pid.2=0x0038
 robotControl.vid.3=0x2A03
 robotControl.pid.3=0x8038
+robotControl.upload_port.0.vid=0x2341
+robotControl.upload_port.0.pid=0x0038
+robotControl.upload_port.1.vid=0x2341
+robotControl.upload_port.1.pid=0x8038
+robotControl.upload_port.2.vid=0x2A03
+robotControl.upload_port.2.pid=0x0038
+robotControl.upload_port.3.vid=0x2A03
+robotControl.upload_port.3.pid=0x8038
+robotControl.upload_port.4.board=robotControl
 
 robotControl.upload.tool=avrdude
+robotControl.upload.tool.default=avrdude
+robotControl.upload.tool.network=arduino_ota
 robotControl.upload.protocol=avr109
 robotControl.upload.maximum_size=28672
 robotControl.upload.maximum_data_size=2560
@@ -258,6 +337,7 @@ robotControl.upload.use_1200bps_touch=true
 robotControl.upload.wait_for_upload_port=true
 
 robotControl.bootloader.tool=avrdude
+robotControl.bootloader.tool.default=avrdude
 robotControl.bootloader.low_fuses=0xff
 robotControl.bootloader.high_fuses=0xd8
 robotControl.bootloader.extended_fuses=0xcb
@@ -286,8 +366,19 @@ robotMotor.vid.2=0x2A03
 robotMotor.pid.2=0x0039
 robotMotor.vid.3=0x2A03
 robotMotor.pid.3=0x8039
+robotMotor.upload_port.0.vid=0x2341
+robotMotor.upload_port.0.pid=0x0039
+robotMotor.upload_port.1.vid=0x2341
+robotMotor.upload_port.1.pid=0x8039
+robotMotor.upload_port.2.vid=0x2A03
+robotMotor.upload_port.2.pid=0x0039
+robotMotor.upload_port.3.vid=0x2A03
+robotMotor.upload_port.3.pid=0x8039
+robotMotor.upload_port.4.board=robotMotor
 
 robotMotor.upload.tool=avrdude
+robotMotor.upload.tool.default=avrdude
+robotMotor.upload.tool.network=arduino_ota
 robotMotor.upload.protocol=avr109
 robotMotor.upload.maximum_size=28672
 robotMotor.upload.maximum_data_size=2560
@@ -297,6 +388,7 @@ robotMotor.upload.use_1200bps_touch=true
 robotMotor.upload.wait_for_upload_port=true
 
 robotMotor.bootloader.tool=avrdude
+robotMotor.bootloader.tool.default=avrdude
 robotMotor.bootloader.low_fuses=0xff
 robotMotor.bootloader.high_fuses=0xd8
 robotMotor.bootloader.extended_fuses=0xcb
@@ -317,7 +409,7 @@ robotMotor.build.extra_flags={build.usb_flags}
 ##############################################################
 
 # Adafruit Circuit Playground 32u4 w/Caterina Configuration w/ XInput
-circuitplay32u4cat.name=Adafruit Circuit Playground
+circuitplay32u4cat.name=Adafruit Circuit Playground 32u4 w/ XInput
 circuitplay32u4cat.bootloader.low_fuses=0xff
 circuitplay32u4cat.bootloader.high_fuses=0xd8
 circuitplay32u4cat.bootloader.extended_fuses=0xcb
@@ -325,6 +417,7 @@ circuitplay32u4cat.bootloader.file=caterina/Caterina-Circuitplay32u4.hex
 circuitplay32u4cat.bootloader.unlock_bits=0x3F
 circuitplay32u4cat.bootloader.lock_bits=0x2F
 circuitplay32u4cat.bootloader.tool=avrdude
+circuitplay32u4cat.bootloader.tool.default=avrdude
 circuitplay32u4cat.build.mcu=atmega32u4
 circuitplay32u4cat.build.f_cpu=8000000L
 circuitplay32u4cat.build.vid=0x045E
@@ -342,8 +435,13 @@ circuitplay32u4cat.upload.disable_flushing=true
 circuitplay32u4cat.upload.use_1200bps_touch=true
 circuitplay32u4cat.upload.wait_for_upload_port=true
 circuitplay32u4cat.upload.tool=avrdude
+circuitplay32u4cat.upload.tool.default=avrdude
+circuitplay32u4cat.upload.tool.network=arduino_ota
 circuitplay32u4cat.vid.0=0x239A
 circuitplay32u4cat.pid.0=0x8011
+circuitplay32u4cat.upload_port.0.vid=0x239A
+circuitplay32u4cat.upload_port.0.pid=0x8011
+circuitplay32u4cat.upload_port.1.board=circuitplay32u4cat
 
 ##############################################################
 
@@ -354,8 +452,15 @@ yunmini.vid.0=0x2a03
 yunmini.pid.0=0x0050
 yunmini.vid.1=0x2a03
 yunmini.pid.1=0x8050
+yunmini.upload_port.0.vid=0x2a03
+yunmini.upload_port.0.pid=0x0050
+yunmini.upload_port.1.vid=0x2a03
+yunmini.upload_port.1.pid=0x8050
+yunmini.upload_port.2.board=yunmini
 
 yunmini.upload.tool=avrdude
+yunmini.upload.tool.default=avrdude
+yunmini.upload.tool.network=arduino_ota
 yunmini.upload.protocol=avr109
 yunmini.upload.maximum_size=28672
 yunmini.upload.maximum_data_size=2560
@@ -365,6 +470,7 @@ yunmini.upload.use_1200bps_touch=true
 yunmini.upload.wait_for_upload_port=true
 
 yunmini.bootloader.tool=avrdude
+yunmini.bootloader.tool.default=avrdude
 yunmini.bootloader.low_fuses=0xff
 yunmini.bootloader.high_fuses=0xd8
 yunmini.bootloader.extended_fuses=0xfb
@@ -391,8 +497,15 @@ chiwawa.vid.0=0x2a03
 chiwawa.pid.0=0x0056
 chiwawa.vid.1=0x2a03
 chiwawa.pid.1=0x8056
+chiwawa.upload_port.0.vid=0x2a03
+chiwawa.upload_port.0.pid=0x0056
+chiwawa.upload_port.1.vid=0x2a03
+chiwawa.upload_port.1.pid=0x8056
+chiwawa.upload_port.2.board=chiwawa
 
 chiwawa.upload.tool=avrdude
+chiwawa.upload.tool.default=avrdude
+chiwawa.upload.tool.network=arduino_ota
 chiwawa.upload.protocol=avr109
 chiwawa.upload.maximum_size=28672
 chiwawa.upload.maximum_data_size=2560
@@ -402,6 +515,7 @@ chiwawa.upload.use_1200bps_touch=true
 chiwawa.upload.wait_for_upload_port=true
 
 chiwawa.bootloader.tool=avrdude
+chiwawa.bootloader.tool.default=avrdude
 chiwawa.bootloader.low_fuses=0xff
 chiwawa.bootloader.high_fuses=0xd8
 chiwawa.bootloader.extended_fuses=0xfb
@@ -428,8 +542,15 @@ one.vid.0=0x2a03
 one.pid.0=0x0001
 one.vid.1=0x2a03
 one.pid.1=0x8001
+one.upload_port.0.vid=0x2a03
+one.upload_port.0.pid=0x0001
+one.upload_port.1.vid=0x2a03
+one.upload_port.1.pid=0x8001
+one.upload_port.2.board=one
 
 one.upload.tool=avrdude
+one.upload.tool.default=avrdude
+one.upload.tool.network=arduino_ota
 one.upload.protocol=avr109
 one.upload.maximum_size=28672
 one.upload.maximum_data_size=2560
@@ -439,6 +560,7 @@ one.upload.use_1200bps_touch=true
 one.upload.wait_for_upload_port=true
 
 one.bootloader.tool=avrdude
+one.bootloader.tool.default=avrdude
 one.bootloader.low_fuses=0xff
 one.bootloader.high_fuses=0xd8
 one.bootloader.extended_fuses=0xfb
diff --git a/cores/arduino/HardwareSerial.cpp b/cores/arduino/HardwareSerial.cpp
index e99d503..561127f 100644
--- a/cores/arduino/HardwareSerial.cpp
+++ b/cores/arduino/HardwareSerial.cpp
@@ -219,7 +219,7 @@ void HardwareSerial::flush()
 	  _tx_udr_empty_irq();
   }
   // If we get here, nothing is queued anymore (DRIE is disabled) and
-  // the hardware finished tranmission (TXC is set).
+  // the hardware finished transmission (TXC is set).
 }
 
 size_t HardwareSerial::write(uint8_t c)
diff --git a/cores/arduino/HardwareSerial.h b/cores/arduino/HardwareSerial.h
index 17000c2..6ff29d0 100644
--- a/cores/arduino/HardwareSerial.h
+++ b/cores/arduino/HardwareSerial.h
@@ -32,7 +32,7 @@
 // using a ring buffer (I think), in which head is the index of the location
 // to which to write the next incoming character and tail is the index of the
 // location from which to read.
-// NOTE: a "power of 2" buffer size is reccomended to dramatically
+// NOTE: a "power of 2" buffer size is recommended to dramatically
 //       optimize all the modulo operations for ring buffers.
 // WARNING: When buffer sizes are increased to > 256, the buffer index
 // variables are automatically increased in size, but the extra
diff --git a/cores/arduino/HardwareSerial_private.h b/cores/arduino/HardwareSerial_private.h
index 761a5e5..2e23cec 100644
--- a/cores/arduino/HardwareSerial_private.h
+++ b/cores/arduino/HardwareSerial_private.h
@@ -63,7 +63,7 @@
 #endif
 #endif // !defined TXC0
 
-// Check at compiletime that it is really ok to use the bit positions of
+// Check at compile time that it is really ok to use the bit positions of
 // UART0 for the other UARTs as well, in case these values ever get
 // changed for future hardware.
 #if defined(TXC1) && (TXC1 != TXC0 || RXEN1 != RXEN0 || RXCIE1 != RXCIE0 || \
diff --git a/cores/arduino/Print.h b/cores/arduino/Print.h
index 058a2ab..0097cc1 100644
--- a/cores/arduino/Print.h
+++ b/cores/arduino/Print.h
@@ -59,7 +59,7 @@ class Print
     }
 
     // default to zero, meaning "a single write may block"
-    // should be overriden by subclasses with buffering
+    // should be overridden by subclasses with buffering
     virtual int availableForWrite() { return 0; }
 
     size_t print(const __FlashStringHelper *);
diff --git a/cores/arduino/Stream.h b/cores/arduino/Stream.h
index 8e950c7..21a247a 100644
--- a/cores/arduino/Stream.h
+++ b/cores/arduino/Stream.h
@@ -25,7 +25,7 @@
 #include <inttypes.h>
 #include "Print.h"
 
-// compatability macros for testing
+// compatibility macros for testing
 /*
 #define   getInt()            parseInt()
 #define   getInt(ignore)    parseInt(ignore)
diff --git a/cores/arduino/USBAPI.h b/cores/arduino/USBAPI.h
index 47221b8..1ad268c 100644
--- a/cores/arduino/USBAPI.h
+++ b/cores/arduino/USBAPI.h
@@ -32,7 +32,7 @@ typedef unsigned long u32;
 
 #include "Arduino.h"
 
-// This definitions is usefull if you want to reduce the EP_SIZE to 16
+// This definitions is useful if you want to reduce the EP_SIZE to 16
 // at the moment only 64 and 16 as EP_SIZE for all EPs are supported except the control endpoint
 #ifndef USB_EP_SIZE
 #define USB_EP_SIZE 64
diff --git a/cores/arduino/WString.h b/cores/arduino/WString.h
index 77709c3..2cf4cd7 100644
--- a/cores/arduino/WString.h
+++ b/cores/arduino/WString.h
@@ -95,7 +95,7 @@ public:
 
 	// returns true on success, false on failure (in which case, the string
 	// is left unchanged).  if the argument is null or invalid, the
-	// concatenation is considered unsucessful.
+	// concatenation is considered unsuccessful.
 	unsigned char concat(const String &str);
 	unsigned char concat(const char *cstr);
 	unsigned char concat(char c);
@@ -152,7 +152,7 @@ public:
 	unsigned char startsWith(const String &prefix, unsigned int offset) const;
 	unsigned char endsWith(const String &suffix) const;
 
-	// character acccess
+	// character access
 	char charAt(unsigned int index) const;
 	void setCharAt(unsigned int index, char c);
 	char operator [] (unsigned int index) const;
diff --git a/cores/arduino/abi.cpp b/cores/arduino/abi.cpp
index 8d719b8..6e1b0f8 100644
--- a/cores/arduino/abi.cpp
+++ b/cores/arduino/abi.cpp
@@ -21,15 +21,16 @@
 extern "C" void __cxa_pure_virtual(void) __attribute__ ((__noreturn__));
 extern "C" void __cxa_deleted_virtual(void) __attribute__ ((__noreturn__));
 
+namespace std {
+  [[gnu::weak, noreturn]] void terminate() {
+    abort();
+  }
+}
+
 void __cxa_pure_virtual(void) {
-  // We might want to write some diagnostics to uart in this case
-  //std::terminate();
-  abort();
+  std::terminate();
 }
 
 void __cxa_deleted_virtual(void) {
-  // We might want to write some diagnostics to uart in this case
-  //std::terminate();
-  abort();
+  std::terminate();
 }
-
diff --git a/cores/arduino/new b/cores/arduino/new
index aa8ecb5..8cf2103 100644
--- a/cores/arduino/new
+++ b/cores/arduino/new
@@ -1,5 +1,66 @@
 /*
-this header is for compatibility with standard c++ header names
-so that #include<new> works as expected
+  Copyright (c) 2014 Arduino.  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
 */
-#include "new.h"
+
+#ifndef NEW_H
+#define NEW_H
+
+#include <stdlib.h>
+
+namespace std {
+  struct nothrow_t {};
+  extern const nothrow_t nothrow;
+
+  // These are not actually implemented, to prevent overhead and
+  // complexity. They are still declared to allow implementing
+  // them in user code if needed.
+  typedef void (*new_handler)();
+  new_handler set_new_handler(new_handler new_p) noexcept;
+  new_handler get_new_handler() noexcept;
+
+  // This is normally declared in various headers that we do not have
+  // available, so just define it here. We could also use ::size_t
+  // below, but then anyone including <new> can no longer assume
+  // std::size_t is available.
+  using size_t = ::size_t;
+} // namespace std
+
+[[gnu::weak]] void * operator new(std::size_t size);
+[[gnu::weak]] void * operator new[](std::size_t size);
+
+[[gnu::weak]] void * operator new(std::size_t size, const std::nothrow_t tag) noexcept;
+[[gnu::weak]] void * operator new[](std::size_t size, const std::nothrow_t& tag) noexcept;
+
+void * operator new(std::size_t size, void *place) noexcept;
+void * operator new[](std::size_t size, void *place) noexcept;
+
+[[gnu::weak]] void operator delete(void * ptr) noexcept;
+[[gnu::weak]] void operator delete[](void * ptr) noexcept;
+
+#if __cplusplus >= 201402L
+[[gnu::weak]] void operator delete(void* ptr, std::size_t size) noexcept;
+[[gnu::weak]] void operator delete[](void * ptr, std::size_t size) noexcept;
+#endif // __cplusplus >= 201402L
+
+[[gnu::weak]] void operator delete(void* ptr, const std::nothrow_t& tag) noexcept;
+[[gnu::weak]] void operator delete[](void* ptr, const std::nothrow_t& tag) noexcept;
+
+void operator delete(void* ptr, void* place) noexcept;
+void operator delete[](void* ptr, void* place) noexcept;
+
+#endif
+
diff --git a/cores/arduino/new.cpp b/cores/arduino/new.cpp
index fc30cf8..7ca4931 100644
--- a/cores/arduino/new.cpp
+++ b/cores/arduino/new.cpp
@@ -16,26 +16,102 @@
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
 
-#include <stdlib.h>
+#include "new.h"
 
-void *operator new(size_t size) {
-  return malloc(size);
+// The C++ spec dictates that allocation failure should cause the
+// (non-nothrow version of the) operator new to throw an exception.
+// Since we expect to have exceptions disabled, it would be more
+// appropriate (and probably standards-compliant) to terminate instead.
+// Historically failure causes null to be returned, but this define
+// allows switching to more robust terminating behaviour (that might
+// become the default at some point in the future). Note that any code
+// that wants null to be returned can (and should) use the nothrow
+// versions of the new statement anyway and is unaffected by this.
+// #define NEW_TERMINATES_ON_FAILURE
+
+namespace std {
+  // Defined in abi.cpp
+  void terminate();
+
+  const nothrow_t nothrow;
 }
 
-void *operator new[](size_t size) {
+static void * new_helper(std::size_t size) {
+  // Even zero-sized allocations should return a unique pointer, but
+  // malloc does not guarantee this
+  if (size == 0)
+    size = 1;
   return malloc(size);
 }
 
-void * operator new(size_t size, void * ptr) noexcept {
-  (void)size;
-  return ptr;
+void * operator new(std::size_t size) {
+  void *res = new_helper(size);
+#if defined(NEW_TERMINATES_ON_FAILURE)
+  if (!res)
+    std::terminate();
+#endif
+  return res;
+}
+void * operator new[](std::size_t size) {
+  return operator new(size);
 }
 
-void operator delete(void * ptr) {
-  free(ptr);
+void * operator new(std::size_t size, const std::nothrow_t tag) noexcept {
+#if defined(NEW_TERMINATES_ON_FAILURE)
+  // Cannot call throwing operator new as standard suggests, so call
+  // new_helper directly then
+  return new_helper(size);
+#else
+  return operator new(size);
+#endif
+}
+void * operator new[](std::size_t size, const std::nothrow_t& tag) noexcept {
+#if defined(NEW_TERMINATES_ON_FAILURE)
+  // Cannot call throwing operator new[] as standard suggests, so call
+  // malloc directly then
+  return new_helper(size);
+#else
+  return operator new[](size);
+#endif
+}
+
+void * operator new(std::size_t size, void *place) noexcept {
+  // Nothing to do
+  (void)size; // unused
+  return place;
+}
+void * operator new[](std::size_t size, void *place) noexcept {
+  return operator new(size, place);
 }
 
-void operator delete[](void * ptr) {
+void operator delete(void * ptr) noexcept {
   free(ptr);
 }
+void operator delete[](void * ptr) noexcept {
+  operator delete(ptr);
+}
 
+#if __cplusplus >= 201402L
+void operator delete(void* ptr, std::size_t size) noexcept {
+  operator delete(ptr);
+}
+void operator delete[](void * ptr, std::size_t size) noexcept {
+  operator delete[](ptr);
+}
+#endif // __cplusplus >= 201402L
+
+void operator delete(void* ptr, const std::nothrow_t& tag) noexcept {
+  operator delete(ptr);
+}
+void operator delete[](void* ptr, const std::nothrow_t& tag) noexcept {
+  operator delete[](ptr);
+}
+
+void operator delete(void* ptr, void* place) noexcept {
+  (void)ptr; (void)place; // unused
+  // Nothing to do
+}
+void operator delete[](void* ptr, void* place) noexcept {
+  (void)ptr; (void)place; // unused
+  // Nothing to do
+}
diff --git a/cores/arduino/new.h b/cores/arduino/new.h
index 763f5cc..d529853 100644
--- a/cores/arduino/new.h
+++ b/cores/arduino/new.h
@@ -1,31 +1,3 @@
-/*
-  Copyright (c) 2014 Arduino.  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
-*/
-
-#ifndef NEW_H
-#define NEW_H
-
-#include <stdlib.h>
-
-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);
-
-#endif
-
+// This file originally used a non-standard name for this Arduino core
+// only, so still expose the old new.h name for compatibility.
+#include "new"
diff --git a/cores/arduino/wiring.c b/cores/arduino/wiring.c
index 9727135..8caf455 100644
--- a/cores/arduino/wiring.c
+++ b/cores/arduino/wiring.c
@@ -125,7 +125,7 @@ void delayMicroseconds(unsigned int us)
 	// 2 microseconds) gives delays longer than desired.
 	//delay_us(us);
 #if F_CPU >= 24000000L
-	// for the 24 MHz clock for the aventurous ones, trying to overclock
+	// for the 24 MHz clock for the adventurous ones trying to overclock
 
 	// zero delay fix
 	if (!us) return; //  = 3 cycles, (4 when true)
@@ -135,9 +135,9 @@ void delayMicroseconds(unsigned int us)
 	// delay requested.
 	us *= 6; // x6 us, = 7 cycles
 
-	// account for the time taken in the preceeding commands.
+	// account for the time taken in the preceding commands.
 	// we just burned 22 (24) cycles above, remove 5, (5*4=20)
-	// us is at least 6 so we can substract 5
+	// us is at least 6 so we can subtract 5
 	us -= 5; //=2 cycles
 
 #elif F_CPU >= 20000000L
@@ -157,9 +157,9 @@ void delayMicroseconds(unsigned int us)
 	// delay requested.
 	us = (us << 2) + us; // x5 us, = 7 cycles
 
-	// account for the time taken in the preceeding commands.
+	// account for the time taken in the preceding commands.
 	// we just burned 26 (28) cycles above, remove 7, (7*4=28)
-	// us is at least 10 so we can substract 7
+	// us is at least 10 so we can subtract 7
 	us -= 7; // 2 cycles
 
 #elif F_CPU >= 16000000L
@@ -174,9 +174,9 @@ void delayMicroseconds(unsigned int us)
 	// delay requested.
 	us <<= 2; // x4 us, = 4 cycles
 
-	// account for the time taken in the preceeding commands.
+	// account for the time taken in the preceding commands.
 	// we just burned 19 (21) cycles above, remove 5, (5*4=20)
-	// us is at least 8 so we can substract 5
+	// us is at least 8 so we can subtract 5
 	us -= 5; // = 2 cycles,
 
 #elif F_CPU >= 12000000L
@@ -191,9 +191,9 @@ void delayMicroseconds(unsigned int us)
 	// delay requested.
 	us = (us << 1) + us; // x3 us, = 5 cycles
 
-	// account for the time taken in the preceeding commands.
+	// account for the time taken in the preceding commands.
 	// we just burned 20 (22) cycles above, remove 5, (5*4=20)
-	// us is at least 6 so we can substract 5
+	// us is at least 6 so we can subtract 5
 	us -= 5; //2 cycles
 
 #elif F_CPU >= 8000000L
@@ -208,9 +208,9 @@ void delayMicroseconds(unsigned int us)
 	// delay requested.
 	us <<= 1; //x2 us, = 2 cycles
 
-	// account for the time taken in the preceeding commands.
+	// account for the time taken in the preceding commands.
 	// we just burned 17 (19) cycles above, remove 4, (4*4=16)
-	// us is at least 6 so we can substract 4
+	// us is at least 6 so we can subtract 4
 	us -= 4; // = 2 cycles
 
 #else
@@ -218,9 +218,9 @@ void delayMicroseconds(unsigned int us)
 
 	// the overhead of the function calls is 14 (16) cycles
 	if (us <= 16) return; //= 3 cycles, (4 when true)
-	if (us <= 25) return; //= 3 cycles, (4 when true), (must be at least 25 if we want to substract 22)
+	if (us <= 25) return; //= 3 cycles, (4 when true), (must be at least 25 if we want to subtract 22)
 
-	// compensate for the time taken by the preceeding and next commands (about 22 cycles)
+	// compensate for the time taken by the preceding and next commands (about 22 cycles)
 	us -= 22; // = 2 cycles
 	// the following loop takes 4 microseconds (4 cycles)
 	// per iteration, so execute it us/4 times
diff --git a/cores/arduino/wiring_analog.c b/cores/arduino/wiring_analog.c
index e237d6d..0de64f7 100644
--- a/cores/arduino/wiring_analog.c
+++ b/cores/arduino/wiring_analog.c
@@ -37,7 +37,6 @@ void analogReference(uint8_t mode)
 
 int analogRead(uint8_t pin)
 {
-	uint8_t low, high;
 
 #if defined(analogPinToChannel)
 #if defined(__AVR_ATmega32U4__)
@@ -74,27 +73,20 @@ int analogRead(uint8_t pin)
 	// without a delay, we seem to read from the wrong channel
 	//delay(1);
 
-#if defined(ADCSRA) && defined(ADCL)
+#if defined(ADCSRA) && defined(ADC)
 	// start the conversion
 	sbi(ADCSRA, ADSC);
 
 	// ADSC is cleared when the conversion finishes
 	while (bit_is_set(ADCSRA, ADSC));
 
-	// we have to read ADCL first; doing so locks both ADCL
-	// and ADCH until ADCH is read.  reading ADCL second would
-	// cause the results of each conversion to be discarded,
-	// as ADCL and ADCH would be locked when it completed.
-	low  = ADCL;
-	high = ADCH;
+	// ADC macro takes care of reading ADC register.
+	// avr-gcc implements the proper reading order: ADCL is read first.
+	return ADC;
 #else
 	// we dont have an ADC, return 0
-	low  = 0;
-	high = 0;
+	return 0;
 #endif
-
-	// combine the two bytes
-	return (high << 8) | low;
 }
 
 // Right now, PWM output only works on the pins with
diff --git a/cores/arduino/wiring_digital.c b/cores/arduino/wiring_digital.c
index 27a62fc..432a150 100644
--- a/cores/arduino/wiring_digital.c
+++ b/cores/arduino/wiring_digital.c
@@ -67,7 +67,7 @@ void pinMode(uint8_t pin, uint8_t mode)
 //
 // Mark Sproul:
 // - Removed inline. Save 170 bytes on atmega1280
-// - changed to a switch statment; added 32 bytes but much easier to read and maintain.
+// - changed to a switch statement; added 32 bytes but much easier to read and maintain.
 // - Added more #ifdefs, now compiles for atmega645
 //
 //static inline void turnOffPWM(uint8_t timer) __attribute__ ((always_inline));
diff --git a/libraries/EEPROM/README.md b/libraries/EEPROM/README.md
index a624136..9ca761d 100644
--- a/libraries/EEPROM/README.md
+++ b/libraries/EEPROM/README.md
@@ -53,7 +53,7 @@ This function does not return any value.
 This function will retrieve any object from the EEPROM.
 Two parameters are needed to call this function. The first is an `int` containing the address that is to be written, and the second is the object you would like to read.
 
-This function returns a reference to the `object` passed in. It does not need to be used and is only returned for conveience.
+This function returns a reference to the `object` passed in. It does not need to be used and is only returned for convenience.
 
 #### **`EEPROM.put( address, object )`** [[_example_]](examples/eeprom_put/eeprom_put.ino)
 
@@ -62,7 +62,7 @@ Two parameters are needed to call this function. The first is an `int` containin
 
 This function uses the _update_ method to write its data, and therefore only rewrites changed cells.
 
-This function returns a reference to the `object` passed in. It does not need to be used and is only returned for conveience.
+This function returns a reference to the `object` passed in. It does not need to be used and is only returned for convenience.
 
 #### **Subscript operator: `EEPROM[address]`** [[_example_]](examples/eeprom_crc/eeprom_crc.ino)
 
@@ -136,4 +136,4 @@ This is useful for STL objects, custom iteration and C++11 style ranged for loop
 This function returns an `EEPtr` pointing at the location after the last EEPROM cell.  
 Used with `begin()` to provide custom iteration.
 
-**Note:** The `EEPtr` returned is invalid as it is out of range. Infact the hardware causes wrapping of the address (overflow) and `EEPROM.end()` actually references the first EEPROM cell.
+**Note:** The `EEPtr` returned is invalid as it is out of range. In fact the hardware causes wrapping of the address (overflow) and `EEPROM.end()` actually references the first EEPROM cell.
diff --git a/libraries/EEPROM/examples/eeprom_clear/eeprom_clear.ino b/libraries/EEPROM/examples/eeprom_clear/eeprom_clear.ino
index 8b5121c..3fed10f 100644
--- a/libraries/EEPROM/examples/eeprom_clear/eeprom_clear.ino
+++ b/libraries/EEPROM/examples/eeprom_clear/eeprom_clear.ino
@@ -18,9 +18,9 @@ void setup() {
     Iterate through each byte of the EEPROM storage.
 
     Larger AVR processors have larger EEPROM sizes, E.g:
-    - Arduno Duemilanove: 512b EEPROM storage.
-    - Arduino Uno:        1kb EEPROM storage.
-    - Arduino Mega:       4kb EEPROM storage.
+    - Arduino Duemilanove: 512 B EEPROM storage.
+    - Arduino Uno:         1 kB EEPROM storage.
+    - Arduino Mega:        4 kB EEPROM storage.
 
     Rather than hard-coding the length, you should use the pre-provided length function.
     This will make your code portable to all AVR processors.
diff --git a/libraries/EEPROM/examples/eeprom_iteration/eeprom_iteration.ino b/libraries/EEPROM/examples/eeprom_iteration/eeprom_iteration.ino
index 3673b47..b5d68be 100644
--- a/libraries/EEPROM/examples/eeprom_iteration/eeprom_iteration.ino
+++ b/libraries/EEPROM/examples/eeprom_iteration/eeprom_iteration.ino
@@ -54,4 +54,4 @@ void setup() {
 
 } //End of setup function.
 
-void loop() {}
\ No newline at end of file
+void loop() {}
diff --git a/libraries/EEPROM/examples/eeprom_read/eeprom_read.ino b/libraries/EEPROM/examples/eeprom_read/eeprom_read.ino
index a8a3510..d465035 100644
--- a/libraries/EEPROM/examples/eeprom_read/eeprom_read.ino
+++ b/libraries/EEPROM/examples/eeprom_read/eeprom_read.ino
@@ -33,9 +33,9 @@ void loop() {
     Advance to the next address, when at the end restart at the beginning.
 
     Larger AVR processors have larger EEPROM sizes, E.g:
-    - Arduno Duemilanove: 512b EEPROM storage.
-    - Arduino Uno:        1kb EEPROM storage.
-    - Arduino Mega:       4kb EEPROM storage.
+    - Arduino Duemilanove: 512 B EEPROM storage.
+    - Arduino Uno:         1 kB EEPROM storage.
+    - Arduino Mega:        4 kB EEPROM storage.
 
     Rather than hard-coding the length, you should use the pre-provided length function.
     This will make your code portable to all AVR processors.
diff --git a/libraries/EEPROM/examples/eeprom_update/eeprom_update.ino b/libraries/EEPROM/examples/eeprom_update/eeprom_update.ino
index 5e3db5b..f5b0c0c 100644
--- a/libraries/EEPROM/examples/eeprom_update/eeprom_update.ino
+++ b/libraries/EEPROM/examples/eeprom_update/eeprom_update.ino
@@ -17,7 +17,7 @@
 int address = 0;
 
 void setup() {
-  /** EMpty setup **/
+  /** Empty setup **/
 }
 
 void loop() {
@@ -48,9 +48,9 @@ void loop() {
     Advance to the next address, when at the end restart at the beginning.
 
     Larger AVR processors have larger EEPROM sizes, E.g:
-    - Arduno Duemilanove: 512b EEPROM storage.
-    - Arduino Uno:        1kb EEPROM storage.
-    - Arduino Mega:       4kb EEPROM storage.
+    - Arduino Duemilanove: 512 B EEPROM storage.
+    - Arduino Uno:         1 kB EEPROM storage.
+    - Arduino Mega:        4 kB EEPROM storage.
 
     Rather than hard-coding the length, you should use the pre-provided length function.
     This will make your code portable to all AVR processors.
diff --git a/libraries/EEPROM/examples/eeprom_write/eeprom_write.ino b/libraries/EEPROM/examples/eeprom_write/eeprom_write.ino
index f9bea64..64e835c 100644
--- a/libraries/EEPROM/examples/eeprom_write/eeprom_write.ino
+++ b/libraries/EEPROM/examples/eeprom_write/eeprom_write.ino
@@ -36,9 +36,9 @@ void loop() {
     Advance to the next address, when at the end restart at the beginning.
 
     Larger AVR processors have larger EEPROM sizes, E.g:
-    - Arduno Duemilanove: 512b EEPROM storage.
-    - Arduino Uno:        1kb EEPROM storage.
-    - Arduino Mega:       4kb EEPROM storage.
+    - Arduino Duemilanove: 512 B EEPROM storage.
+    - Arduino Uno:         1 kB EEPROM storage.
+    - Arduino Mega:        4 kB EEPROM storage.
 
     Rather than hard-coding the length, you should use the pre-provided length function.
     This will make your code portable to all AVR processors.
diff --git a/libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor.ino b/libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor.ino
index df73ade..1b8ad70 100644
--- a/libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor.ino
+++ b/libraries/SPI/examples/BarometricPressureSensor/BarometricPressureSensor.ino
@@ -43,7 +43,7 @@ void setup() {
   // start the SPI library:
   SPI.begin();
 
-  // initalize the  data ready and chip select pins:
+  // initialize the  data ready and chip select pins:
   pinMode(dataReadyPin, INPUT);
   pinMode(chipSelectPin, OUTPUT);
 
@@ -140,4 +140,3 @@ void writeRegister(byte thisRegister, byte thisValue) {
   // take the chip select high to de-select:
   digitalWrite(chipSelectPin, HIGH);
 }
-
diff --git a/libraries/SPI/examples/DigitalPotControl/DigitalPotControl.ino b/libraries/SPI/examples/DigitalPotControl/DigitalPotControl.ino
index 8719058..39e5bf9 100644
--- a/libraries/SPI/examples/DigitalPotControl/DigitalPotControl.ino
+++ b/libraries/SPI/examples/DigitalPotControl/DigitalPotControl.ino
@@ -14,7 +14,7 @@
  The circuit:
   * All A pins  of AD5206 connected to +5V
   * All B pins of AD5206 connected to ground
-  * An LED and a 220-ohm resisor in series connected from each W pin to ground
+  * An LED and a 220-ohm resistor in series connected from each W pin to ground
   * CS - to digital pin 10  (SS pin)
   * SDI - to digital pin 11 (MOSI pin)
   * CLK - to digital pin 13 (SCK pin)
@@ -27,7 +27,7 @@
 */
 
 
-// inslude the SPI library:
+// include the SPI library:
 #include <SPI.h>
 
 
@@ -64,7 +64,7 @@ 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:
+  // send in the address and value via SPI:
   SPI.transfer(address);
   SPI.transfer(value);
   delay(100);
diff --git a/libraries/SPI/src/SPI.h b/libraries/SPI/src/SPI.h
index 5206a09..1e37079 100644
--- a/libraries/SPI/src/SPI.h
+++ b/libraries/SPI/src/SPI.h
@@ -106,7 +106,7 @@ private:
     // slowest (128 == 2 ^^ 7, so clock_div = 6).
     uint8_t clockDiv;
 
-    // When the clock is known at compiletime, use this if-then-else
+    // When the clock is known at compile time, use this if-then-else
     // cascade, which the compiler knows how to completely optimize
     // away. When clock is not known, use a loop instead, which generates
     // shorter code.
diff --git a/libraries/SoftwareSerial/examples/SoftwareSerialExample/SoftwareSerialExample.ino b/libraries/SoftwareSerial/examples/SoftwareSerialExample/SoftwareSerialExample.ino
index 61ce88c..061bb70 100644
--- a/libraries/SoftwareSerial/examples/SoftwareSerialExample/SoftwareSerialExample.ino
+++ b/libraries/SoftwareSerial/examples/SoftwareSerialExample/SoftwareSerialExample.ino
@@ -1,5 +1,5 @@
 /*
-  Software serial multple serial test
+  Software serial multiple serial test
 
  Receives from the hardware serial, sends to software serial.
  Receives from software serial, sends to hardware serial.
@@ -52,4 +52,3 @@ void loop() { // run over and over
     mySerial.write(Serial.read());
   }
 }
-
diff --git a/libraries/SoftwareSerial/examples/TwoPortReceive/TwoPortReceive.ino b/libraries/SoftwareSerial/examples/TwoPortReceive/TwoPortReceive.ino
index 8d7f93e..d8c064b 100644
--- a/libraries/SoftwareSerial/examples/TwoPortReceive/TwoPortReceive.ino
+++ b/libraries/SoftwareSerial/examples/TwoPortReceive/TwoPortReceive.ino
@@ -1,5 +1,5 @@
 /*
-  Software serial multple serial test
+  Software serial multiple serial test
 
  Receives from the two software serial ports,
  sends to the hardware serial port.
@@ -56,7 +56,7 @@ void setup() {
 }
 
 void loop() {
-  // By default, the last intialized port is listening.
+  // By default, the last initialized port is listening.
   // when you want to listen on a port, explicitly select it:
   portOne.listen();
   Serial.println("Data from port one:");
@@ -83,9 +83,3 @@ void loop() {
   // blank line to separate data from the two ports:
   Serial.println();
 }
-
-
-
-
-
-
diff --git a/libraries/SoftwareSerial/src/SoftwareSerial.cpp b/libraries/SoftwareSerial/src/SoftwareSerial.cpp
index 3163d7a..5a387ab 100644
--- a/libraries/SoftwareSerial/src/SoftwareSerial.cpp
+++ b/libraries/SoftwareSerial/src/SoftwareSerial.cpp
@@ -409,7 +409,7 @@ int SoftwareSerial::available()
   if (!isListening())

     return 0;

 

-  return (_receive_buffer_tail + _SS_MAX_RX_BUFF - _receive_buffer_head) % _SS_MAX_RX_BUFF;

+  return ((unsigned int)(_receive_buffer_tail + _SS_MAX_RX_BUFF - _receive_buffer_head)) % _SS_MAX_RX_BUFF;

 }

 

 size_t SoftwareSerial::write(uint8_t b)

diff --git a/libraries/Wire/examples/SFRRanger_reader/SFRRanger_reader.ino b/libraries/Wire/examples/SFRRanger_reader/SFRRanger_reader.ino
index 4d0a68f..aeb1a9c 100644
--- a/libraries/Wire/examples/SFRRanger_reader/SFRRanger_reader.ino
+++ b/libraries/Wire/examples/SFRRanger_reader/SFRRanger_reader.ino
@@ -3,7 +3,7 @@
 // and James Tichenor <http://www.jamestichenor.net>
 
 // Demonstrates use of the Wire library reading data from the
-// Devantech Utrasonic Rangers SFR08 and SFR10
+// Devantech Ultrasonic Rangers SFR08 and SFR10
 
 // Created 29 April 2006
 
@@ -13,8 +13,8 @@
 #include <Wire.h>
 
 void setup() {
-  Wire.begin();                // join i2c bus (address optional for master)
-  Serial.begin(9600);          // start serial communication at 9600bps
+  Wire.begin();                // join I2C bus (address optional for master)
+  Serial.begin(9600);          // start serial communication at 9600 bps
 }
 
 int reading = 0;
@@ -23,7 +23,7 @@ void loop() {
   // step 1: instruct sensor to read echoes
   Wire.beginTransmission(112); // transmit to device #112 (0x70)
   // the address specified in the datasheet is 224 (0xE0)
-  // but i2c adressing uses the high 7 bits so it's 112
+  // but I2C addressing uses the high 7 bits so it's 112
   Wire.write(byte(0x00));      // sets register pointer to the command register (0x00)
   Wire.write(byte(0x50));      // command sensor to measure in "inches" (0x50)
   // use 0x51 for centimeters
diff --git a/libraries/Wire/examples/digital_potentiometer/digital_potentiometer.ino b/libraries/Wire/examples/digital_potentiometer/digital_potentiometer.ino
index dd40a25..b5da366 100644
--- a/libraries/Wire/examples/digital_potentiometer/digital_potentiometer.ino
+++ b/libraries/Wire/examples/digital_potentiometer/digital_potentiometer.ino
@@ -13,7 +13,7 @@
 #include <Wire.h>
 
 void setup() {
-  Wire.begin(); // join i2c bus (address optional for master)
+  Wire.begin(); // join I2C bus (address optional for master)
 }
 
 byte val = 0;
@@ -31,4 +31,3 @@ void loop() {
   }
   delay(500);
 }
-
diff --git a/libraries/Wire/examples/i2c_scanner/i2c_scanner.ino b/libraries/Wire/examples/i2c_scanner/i2c_scanner.ino
index 3febbf4..295edf7 100644
--- a/libraries/Wire/examples/i2c_scanner/i2c_scanner.ino
+++ b/libraries/Wire/examples/i2c_scanner/i2c_scanner.ino
@@ -5,7 +5,7 @@
 //    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.
+//    The original author is not known.
 // 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
@@ -33,7 +33,7 @@ void setup() {
   Wire.begin();
 
   Serial.begin(9600);
-  while (!Serial); // Leonardo: wait for serial monitor
+  while (!Serial); // Leonardo: wait for Serial Monitor
   Serial.println("\nI2C Scanner");
 }
 
@@ -44,7 +44,7 @@ void loop() {
 
   for (byte address = 1; address < 127; ++address) {
     // The i2c_scanner uses the return value of
-    // the Write.endTransmisstion to see if
+    // the Wire.endTransmission to see if
     // a device did acknowledge to the address.
     Wire.beginTransmission(address);
     byte error = Wire.endTransmission();
diff --git a/libraries/Wire/examples/master_reader/master_reader.ino b/libraries/Wire/examples/master_reader/master_reader.ino
index ecab72a..e27cac3 100644
--- a/libraries/Wire/examples/master_reader/master_reader.ino
+++ b/libraries/Wire/examples/master_reader/master_reader.ino
@@ -13,7 +13,7 @@
 #include <Wire.h>
 
 void setup() {
-  Wire.begin();        // join i2c bus (address optional for master)
+  Wire.begin();        // join I2C bus (address optional for master)
   Serial.begin(9600);  // start serial for output
 }
 
diff --git a/libraries/Wire/examples/master_writer/master_writer.ino b/libraries/Wire/examples/master_writer/master_writer.ino
index 5cbea11..7a17668 100644
--- a/libraries/Wire/examples/master_writer/master_writer.ino
+++ b/libraries/Wire/examples/master_writer/master_writer.ino
@@ -13,7 +13,7 @@
 #include <Wire.h>
 
 void setup() {
-  Wire.begin(); // join i2c bus (address optional for master)
+  Wire.begin(); // join I2C bus (address optional for master)
 }
 
 byte x = 0;
diff --git a/libraries/Wire/examples/slave_receiver/slave_receiver.ino b/libraries/Wire/examples/slave_receiver/slave_receiver.ino
index 8051d53..9b3f814 100644
--- a/libraries/Wire/examples/slave_receiver/slave_receiver.ino
+++ b/libraries/Wire/examples/slave_receiver/slave_receiver.ino
@@ -13,7 +13,7 @@
 #include <Wire.h>
 
 void setup() {
-  Wire.begin(8);                // join i2c bus with address #8
+  Wire.begin(8);                // join I2C bus with address #8
   Wire.onReceive(receiveEvent); // register event
   Serial.begin(9600);           // start serial for output
 }
diff --git a/libraries/Wire/examples/slave_sender/slave_sender.ino b/libraries/Wire/examples/slave_sender/slave_sender.ino
index d2e72bb..6e2ed49 100644
--- a/libraries/Wire/examples/slave_sender/slave_sender.ino
+++ b/libraries/Wire/examples/slave_sender/slave_sender.ino
@@ -13,7 +13,7 @@
 #include <Wire.h>
 
 void setup() {
-  Wire.begin(8);                // join i2c bus with address #8
+  Wire.begin(8);                // join I2C bus with address #8
   Wire.onRequest(requestEvent); // register event
 }
 
diff --git a/libraries/Wire/src/Wire.cpp b/libraries/Wire/src/Wire.cpp
index c407776..001d924 100644
--- a/libraries/Wire/src/Wire.cpp
+++ b/libraries/Wire/src/Wire.cpp
@@ -100,7 +100,7 @@ void TwoWire::setClock(uint32_t clock)
  * when `clearWireTimeoutFlag()` or `setWireTimeoutUs()` is called.
  *
  * Note that this timeout can also trigger while waiting for clock stretching or waiting for a second master
- * to complete its transaction. So make sure to adapt the timeout to accomodate for those cases if needed.
+ * to complete its transaction. So make sure to adapt the timeout to accommodate for those cases if needed.
  * A typical timeout would be 25ms (which is the maximum clock stretching allowed by the SMBus protocol),
  * but (much) shorter values will usually also work.
  *
@@ -120,7 +120,7 @@ void TwoWire::setWireTimeout(uint32_t timeout, bool reset_with_timeout){
 /***
  * Returns the TWI timeout flag.
  *
- * @return true if timeout has occured since the flag was last cleared.
+ * @return true if timeout has occurred since the flag was last cleared.
  */
 bool TwoWire::getWireTimeoutFlag(void){
   return(twi_manageTimeoutFlag(false));
diff --git a/libraries/Wire/src/utility/twi.c b/libraries/Wire/src/utility/twi.c
index e8a41a2..e09a33c 100644
--- a/libraries/Wire/src/utility/twi.c
+++ b/libraries/Wire/src/utility/twi.c
@@ -175,7 +175,7 @@ uint8_t twi_readFrom(uint8_t address, uint8_t* data, uint8_t length, uint8_t sen
   }
   twi_state = TWI_MRX;
   twi_sendStop = sendStop;
-  // reset error state (0xFF.. no error occured)
+  // reset error state (0xFF.. no error occurred)
   twi_error = 0xFF;
 
   // initialize buffer iteration vars
@@ -183,7 +183,7 @@ uint8_t twi_readFrom(uint8_t address, uint8_t* data, uint8_t length, uint8_t sen
   twi_masterBufferLength = length-1;  // This is not intuitive, read on...
   // On receive, the previously configured ACK/NACK setting is transmitted in
   // response to the received byte before the interrupt is signalled. 
-  // Therefor we must actually set NACK when the _next_ to last byte is
+  // Therefore we must actually set NACK when the _next_ to last byte is
   // received, causing that NACK to be sent in response to receiving the last
   // expected byte of data.
 
@@ -269,7 +269,7 @@ uint8_t twi_writeTo(uint8_t address, uint8_t* data, uint8_t length, uint8_t wait
   }
   twi_state = TWI_MTX;
   twi_sendStop = sendStop;
-  // reset error state (0xFF.. no error occured)
+  // reset error state (0xFF.. no error occurred)
   twi_error = 0xFF;
 
   // initialize buffer iteration vars
@@ -294,7 +294,7 @@ uint8_t twi_writeTo(uint8_t address, uint8_t* data, uint8_t length, uint8_t wait
     // We need to remove ourselves from the repeated start state before we enable interrupts,
     // since the ISR is ASYNC, and we could get confused if we hit the ISR before cleaning
     // up. Also, don't enable the START interrupt. There may be one pending from the 
-    // repeated start that we sent outselves, and that would really confuse things.
+    // repeated start that we sent ourselves, and that would really confuse things.
     twi_inRepStart = false;			// remember, we're dealing with an ASYNC ISR
     startMicros = micros();
     do {
@@ -411,7 +411,7 @@ void twi_stop(void)
   // send stop condition
   TWCR = _BV(TWEN) | _BV(TWIE) | _BV(TWEA) | _BV(TWINT) | _BV(TWSTO);
 
-  // wait for stop condition to be exectued on bus
+  // wait for stop condition to be executed on bus
   // TWINT is not set after a stop condition!
   // We cannot use micros() from an ISR, so approximate the timeout with cycle-counted delays
   const uint8_t us_per_loop = 8;
@@ -490,7 +490,7 @@ void twi_handleTimeout(bool reset){
  * Desc     returns true if twi has seen a timeout
  *          optionally clears the timeout flag
  * Input    clear_flag: true if we should reset the hardware
- * Output   none
+ * Output   the value of twi_timed_out_flag when the function was called
  */
 bool twi_manageTimeoutFlag(bool clear_flag){
   bool flag = twi_timed_out_flag;
diff --git a/platform.txt b/platform.txt
index 93eef8e..345b979 100644
--- a/platform.txt
+++ b/platform.txt
@@ -3,7 +3,7 @@
 # ------------------------------
 #
 # For more info:
-# https://github.com/arduino/Arduino/wiki/Arduino-IDE-1.5-3rd-party-Hardware-specification
+# https://arduino.github.io/arduino-cli/latest/platform-specification/
 
 name=XInput AVR Boards
 version=1.0.2
@@ -89,6 +89,12 @@ recipe.preproc.includes="{compiler.path}{compiler.cpp.cmd}" {compiler.cpp.flags}
 preproc.macros.flags=-w -x c++ -E -CC
 recipe.preproc.macros="{compiler.path}{compiler.cpp.cmd}" {compiler.cpp.flags} {preproc.macros.flags} -mmcu={build.mcu} -DF_CPU={build.f_cpu} -DARDUINO={runtime.ide.version} -DARDUINO_{build.board} -DARDUINO_ARCH_{build.arch} {compiler.cpp.extra_flags} {build.extra_flags} {includes} "{source_file}" -o "{preprocessed_file_path}"
 
+# Required discoveries and monitors
+# ---------------------------------
+pluggable_discovery.required.0=builtin:serial-discovery
+pluggable_discovery.required.1=builtin:mdns-discovery
+pluggable_monitor.required.serial=builtin:serial-monitor
+
 # AVR Uploader/Programmers tools
 # ------------------------------
 
@@ -96,8 +102,6 @@ tools.avrdude.path={runtime.tools.avrdude.path}
 tools.avrdude.cmd.path={path}/bin/avrdude
 tools.avrdude.config.path={path}/etc/avrdude.conf
 
-tools.avrdude.network_cmd={runtime.tools.arduinoOTA.path}/bin/arduinoOTA
-
 tools.avrdude.upload.params.verbose=-v
 tools.avrdude.upload.params.quiet=-q -q
 # tools.avrdude.upload.verify is needed for backwards compatibility with IDE 1.6.8 or older, IDE 1.6.9 or newer overrides this value
@@ -122,7 +126,12 @@ tools.avrdude.bootloader.pattern="{cmd.path}" "-C{config.path}" {bootloader.verb
 
 tools.avrdude_remote.upload.pattern=/usr/bin/run-avrdude /tmp/sketch.hex {upload.verbose} -p{build.mcu}
 
-tools.avrdude.upload.network_pattern="{network_cmd}" -address {serial.port} -port {upload.network.port} -sketch "{build.path}/{build.project_name}.hex" -upload {upload.network.endpoint_upload} -sync {upload.network.endpoint_sync} -reset {upload.network.endpoint_reset} -sync_exp {upload.network.sync_return}
+# the following rule is deprecated by pluggable discovery
+tools.avrdude.upload.network_pattern="{tools.arduino_ota.cmd}" -address {serial.port} -port {upload.network.port} -sketch "{build.path}/{build.project_name}.hex" -upload {upload.network.endpoint_upload} -sync {upload.network.endpoint_sync} -reset {upload.network.endpoint_reset} -sync_exp {upload.network.sync_return}
+
+# arduino ota
+tools.arduino_ota.cmd={runtime.tools.arduinoOTA.path}/bin/arduinoOTA
+tools.arduino_ota.upload.pattern="{cmd}" -address {upload.port.address} -port {upload.port.properties.port} -sketch "{build.path}/{build.project_name}.hex" -upload {upload.port.properties.endpoint_upload} -sync {upload.port.properties.endpoint_sync} -reset {upload.port.properties.endpoint_reset} -sync_exp {upload.port.properties.sync_return}
 
 # USB Default Flags
 # Default blank usb manufacturer will be filled in at compile time