Merge branch 'master' into debug-serialusb.

Chose debug-serialusb version in cases of conflict.

Conflicts:
	libmaple/usb/usb_callbacks.c

1 files changed, 55 insertions, 0 deletions

diff --git a/docs/source/lang/cpp/unsignedint.rst b/docs/source/lang/cpp/unsignedint.rst
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+.. highlight:: cpp
+
+.. _lang-unsignedint:
+
+``unsigned int``
+================
+
+An ``unsigned int`` (unsigned integer) is the same as an :ref:`int
+<lang-int>` in that it stores a 4 byte integer value.  However,
+Instead of storing both negative and positive numbers, an ``unsigned
+int`` can only store nonnegative values, yielding a range of 0 to
+4,294,967,295 (the positive value is 2^32 - 1).
+
+The difference between an ``unsigned int`` and a (signed) ``int`` lies
+in the way the highest bit, sometimes referred to as the "sign" bit,
+is interpreted.  In the case of the Maple ``int`` type (which is
+signed), if the high bit is a "1", the number is interpreted as a
+negative number, using a technique known as `two's complement math
+<http://en.wikipedia.org/wiki/Two%27s_complement#Explanation>`_.  The
+bits in an an ``unsigned int`` are interpreted according to the usual
+rules for converting `binary to decimal
+<http://en.wikipedia.org/wiki/Binary_numeral_system#Counting_in_binary>`_.
+
+An ``unsigned int`` is subject to the same :ref:`overflow issues
+<lang-int-overflow>` as a regular ``int``; the only difference is
+that an ``unsigned int`` will "underflow" at 0, and "overflow" at
+4,294,967,295.  Here is some example code which illustrates this::
+
+       unsigned int x;
+       x = 0;
+       x--; // x now contains 4,294,967,295; rolled over "left to right"
+       x++; // x now contains 0; rolled over "right to left"
+
+Here is an example of declaring an ``unsigned int`` variable named
+``ledPin``, then giving it value 13::
+
+        unsigned int ledPin = 13;
+
+The general syntax for declaring an ``unsigned int`` variable named
+``var``, then giving it value ``val``, looks like::
+
+         unsigned int var = val;
+
+See Also
+--------
+
+-  :ref:`int <lang-int>`
+-  :ref:`char <lang-char>`
+-  :ref:`unsigned char <lang-unsignedchar>`
+-  :ref:`long <lang-long>`
+-  :ref:`unsigned long <lang-unsignedlong>`
+-  :ref:`Integer Constants <lang-constants-integers>`
+-  :ref:`Variables <lang-variables>`
+
+.. include:: cc-attribution.txt