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authorMarti Bolivar <mbolivar@mit.edu>2010-10-20 06:46:52 -0400
committerMarti Bolivar <mbolivar@mit.edu>2010-10-20 06:46:52 -0400
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+.. _arduino-int:
+
+int
+===
+
+Description
+-----------
+
+Integers are your primary datatype for number storage, and store a
+2 byte value. This yields a range of -32,768 to 32,767 (minimum
+value of -2^15 and a maximum value of (2^15) - 1).
+
+
+
+Int's store negative numbers with a technique called
+`2's complement math. <http://en.wikipedia.org/wiki/2's_complement>`_
+The highest bit, sometimes refered to as the "sign" bit, flags the
+number as a negative number. The rest of the bits are inverted and
+1 is added.
+
+
+
+The Arduino takes care of dealing with negative numbers for you, so
+that arithmetic operations work transparently in the expected
+manner. There can be an unexpected complication in dealing with the
+`bitshift right operator (>>) <http://arduino.cc/en/Reference/Bitshift>`_
+however.
+
+
+
+Example
+-------
+
+::
+
+ int ledPin = 13;
+
+
+
+Syntax
+------
+
+::
+
+ int var = val;
+
+
+
+
+- var - your int variable name
+- val - the value you assign to that variable
+
+
+
+Coding Tip
+----------
+
+When variables are made to exceed their maximum capacity they "roll
+over" back to their minimum capacitiy, note that this happens in
+both directions.
+
+
+
+::
+
+ int x
+ x = -32,768;
+ x = x - 1; // x now contains 32,767 - rolls over in neg. direction
+
+ x = 32,767;
+ x = x + 1; // x now contains -32,768 - rolls over
+
+
+
+See Also
+--------
+
+
+- `byte <http://arduino.cc/en/Reference/Byte>`_
+- `unsigned int <http://arduino.cc/en/Reference/UnsignedInt>`_
+- `long <http://arduino.cc/en/Reference/Long>`_
+- `unsigned long <http://arduino.cc/en/Reference/UnsignedLong>`_
+- `Integer Constants <http://arduino.cc/en/Reference/IntegerConstants>`_
+- `Variable Declaration <http://arduino.cc/en/Reference/VariableDeclaration>`_