4 files changed, 79 insertions, 11 deletions
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/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/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