Merge branch 'master' into debug-serialusb.

Chose debug-serialusb version in cases of conflict.

Conflicts:
	libmaple/usb/usb_callbacks.c

54 files changed, 3963 insertions, 0 deletions

diff --git a/docs/source/lang/cpp/arithmetic.rst b/docs/source/lang/cpp/arithmetic.rst
new file mode 100644
index 0000000..91fe22e
--- /dev/null
+++ b/docs/source/lang/cpp/arithmetic.rst
@@ -0,0 +1,127 @@
+.. highlight:: cpp
+
+.. _lang-arithmetic:
+
+Arithmetic Operators (``+``, ``-``, ``*``, ``/``)
+=================================================
+
+The operators ``+``, ``-``, ``*``, and ``/`` respectively evaluate to
+the sum, difference, product, or quotient (respectively) of the two
+operands. The operation is conducted using the data type of the
+operands, so, for example, ``9 / 4`` gives ``2`` since 9 and 4 are
+:ref:`int variables <lang-int>`.
+
+This also means that the operation can overflow if the result is
+larger than that which can be stored in the data type (e.g. adding 1
+to an :ref:`lang-int` with the value 2,147,483,647 gives
+-2,147,483,648).
+
+.. _lang-arithmetic-typeconversion:
+
+If the operands are of different types, the "larger" type is used for
+the calculation.  If one of the numbers (operands) are of the type
+**float** or of type **double**, floating point math will be used for
+the calculation.
+
+.. note:: The specifics of these rules are beyond the scope of this
+   documentation; for more information, see `The C++ Programming
+   Language <http://www2.research.att.com/~bs/3rd.html>`_\ , by Bjarne
+   Stroustroup, Appendix C, especially §§C.4-C.6, or `this WikiBooks
+   entry on C++ type conversion
+   <http://en.wikibooks.org/wiki/C%2B%2B_Programming/Programming_Languages/C%2B%2B/Code/Statements/Variables/Type_Casting#Automatic_type_conversion>`_.
+
+.. note:: For more information on how computers represent integers,
+   see the Wikipedia page on `two's complement
+   <http://en.wikipedia.org/wiki/Two's_complement>`_.
+
+.. contents:: Contents
+   :local:
+
+Examples
+--------
+
+ ::
+
+    y = y + 3;
+    x = x - 7;
+    i = j * 6;
+    r = r / 5;
+
+
+Syntax
+------
+
+ ::
+
+    result = value1 + value2;
+    result = value1 - value2;
+    result = value1 * value2;
+    result = value1 / value2;
+
+
+Parameters
+----------
+
+**value1**: any numeric variable or constant
+
+**value2**: any numeric variable or constant
+
+Programming Tips
+----------------
+
+- Know that :ref:`integer constants <lang-constants-integers>`
+  default to :ref:`int <lang-int>`, so some constant calculations
+  may overflow (e.g., 200000 * 5000000 will yield a negative result).
+
+- Choose variable sizes that are large enough to hold the largest
+  results from your calculations.
+
+- Know at what point your variable will "roll over" and also what
+  happens in the other direction e.g. (0 - 1) for unsigned arithmetic,
+  or (0 - -2,147,483,648) for signed arithmetic.
+
+- For math that requires fractions, float variables may be used, but
+  be aware of their drawbacks: large size and slow computation speeds
+  (the STM32 has no floating point hardware, so all floating point
+  calculations have to be done in software).
+
+- Use cast operator, e.g. ``(int)myFloat`` to convert one variable type
+  to another on the fly.
+
+Arduino Compatibility
+---------------------
+
+Since the STM32 processor on the Maple is a 32-bit machine, the int
+type overflows at a much higher value on Maple than on Arduino.  In
+particular, on Maple, ints do not overflow (become negative) until
+they reach 2,147,483,648; on the Arduino, they overflow at 32,767.
+Because of this, programs running on Maple are much less likely to run
+into overflow issues.  The following table summarizes the sizes and
+ranges of integer datatypes on the Maple (the ranges of long long
+types are approximate):
+
+.. _lang-arithmetic-int-sizes:
+
+.. csv-table::
+   :header: Datatype, Unsigned range, Signed range, Size (bytes)
+   :widths: 8, 12, 17, 8
+
+   ``char``, 0 --- 255, -128 --- 127, 1
+   ``short``, "0 --- 65,535", "-32,768 --- 32,767", 2
+   ``int``,  "0 --- 4,294,967,295", "-2,147,483,648 --- 2,147,483,647", 4
+   ``long``, "0 --- 4,294,967,295", "-2,147,483,648 --- 2,147,483,647", 4
+   ``long long``, "0 --- 1.8*10\ :sup:`19`\ " (approx.), "-9.2*10\ :sup:`18` --- 9.2*10\ :sup:`18` (approx.)", 8
+
+
+See Also
+--------
+
+- The individual sizes (in bits) of various available types are
+  defined in `libmaple_types.h
+  <http://github.com/leaflabs/libmaple/blob/master/libmaple/libmaple_types.h>`_\
+  .
+
+- :ref:`sizeof <lang-sizeof>`\ ()
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/array.rst b/docs/source/lang/cpp/array.rst
new file mode 100644
index 0000000..30a818f
--- /dev/null
+++ b/docs/source/lang/cpp/array.rst
@@ -0,0 +1,123 @@
+.. highlight:: cpp
+
+.. _lang-array:
+
+Arrays
+======
+
+An array is a collection of variables that are accessed with an index
+number. Arrays in the C++ programming language, in which the Maple is
+programmed, can be complicated, but using simple arrays is relatively
+straightforward.
+
+.. contents:: Contents
+   :local:
+
+Creating (Declaring) an Array
+-----------------------------
+
+All of the methods below are valid ways to create (declare) an
+array. ::
+
+      int myInts[6];
+      int myPins[] = {2, 4, 8, 3, 6};
+      int mySensVals[6] = {2, 4, -8, 3, 2};
+      char message[6] = "hello";
+
+You can declare an array without initializing it, as with myInts.  In
+the line referring to myPins, we declare an array without explicitly
+choosing a size.  The compiler counts the elements and creates an
+array of the appropriate size.
+
+Finally, you can both initialize and size your array, as in
+mySensVals. Note that when declaring an array with elements of type
+char, one more element than your initialization is required, to hold
+the required `null character <http://en.wikipedia.org/wiki/Null-terminated_string>`_.
+
+
+Accessing an Array
+------------------
+
+
+.. compound::
+
+   Arrays are **zero indexed**; that is, referring to the array
+   initialization above, the first element of the array is at index 0,
+   hence ::
+
+      mySensVals[0] == 2;
+      mySensVals[1] == 4
+
+   and so forth.
+
+It also means that in an array with ten elements, index nine is the
+last element. Hence::
+
+    int myArray[10]={9,3,2,4,3,2,7,8,9,11};
+         // myArray[9]    contains 11
+         // myArray[10]   is invalid and contains random information (other memory address)
+
+For this reason, you should be careful in accessing arrays.  Accessing
+past the end of an array (using an index number greater than your
+declared array size - 1) is reading from memory that is in use for
+other purposes. Reading from these locations is probably not going to
+do much except yield invalid data. Writing to random memory locations
+is definitely a bad idea, and can often lead to unhappy results such
+as crashes or program malfunction. This can also be a difficult bug to
+track down.
+
+Unlike Basic or Java, the C compiler does no checking to see if array
+access is within legal bounds of the array size that you have
+declared.
+
+
+To assign a value to an array
+-----------------------------
+ ::
+
+    mySensVals[0] = 10;
+
+
+To retrieve a value from an array
+---------------------------------
+
+ ::
+
+    x = mySensVals[4];
+
+
+Arrays and ``for`` Loops
+------------------------
+
+Arrays are often manipulated inside :ref:`for loops <lang-for>`, where
+the loop counter is used as the index for each array element. For
+example, to print the elements of an array over the serial port, you
+could do something like this::
+
+    int i;
+    for (i = 0; i < 5; i = i + 1) {
+      SerialUSB.println(myPins[i]);
+    }
+
+
+Example
+-------
+
+For a complete program that demonstrates the use of arrays, see the
+Arduino `Knight Rider example
+<http://www.arduino.cc/en/Tutorial/KnightRider>`_\ (which will run
+unmodified on the Maple).
+
+Arduino Compatibility
+---------------------
+
+Arrays on Maple are identical those on Arduino.
+
+See also
+--------
+
+-  :ref:`Storing arrays in FLASH memory <arm-gcc-attribute-flash>`
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/assignment.rst b/docs/source/lang/cpp/assignment.rst
new file mode 100644
index 0000000..b6ad4d5
--- /dev/null
+++ b/docs/source/lang/cpp/assignment.rst
@@ -0,0 +1,70 @@
+.. highlight:: cpp
+
+.. _lang-assignment:
+
+Assignment Operator (``=``)
+===========================
+
+Stores the value to the right of the equal sign in the variable to
+the left of the equal sign.
+
+The single equal sign in the C++ programming language is called the
+assignment operator. It has a different meaning than in algebra
+class, where it indicated an equation or equality. The assignment
+operator tells the microcontroller to evaluate whatever value or
+expression is on the right side of the equal sign, and store it in
+the variable to the left of the equal sign [#fgross]_.
+
+
+
+Example
+-------
+
+::
+
+     int sensVal;                  // declare an integer variable named sensVal
+     senVal = analogRead(0);       // store the (digitized) input voltage at analog pin 0 in SensVal
+
+
+
+Programming Tips
+----------------
+
+The variable on the left side of the assignment operator ( = sign )
+needs to be able to hold the value stored in it. If it is not large
+enough to hold a value, the value stored in the variable will be
+incorrect.
+
+Don't confuse the assignment operator [ = ] (single equal sign)
+with the comparison operator [ == ] (double equal signs), which
+evaluates whether two expressions are equal.
+
+
+Arduino Compatibility
+---------------------
+
+Assignments on the Maple are identical to those on Arduino.
+
+
+
+See Also
+--------
+
+
+-  `if (comparison operators) <http://arduino.cc/en/Reference/If>`_
+-  `char <http://arduino.cc/en/Reference/Char>`_
+-  `int <http://arduino.cc/en/Reference/Int>`_
+-  `long <http://arduino.cc/en/Reference/Long>`_
+
+
+.. rubric:: Footnotes
+
+.. [#fgross] Experienced C++ programmers know this to be an
+   oversimplification of what happens when the variable on the left
+   hand side is an object.  See Richard Gillam's wonderful and scary
+   `The Anatomy of the Assignment Operator
+   <http://icu-project.org/docs/papers/cpp_report/the_anatomy_of_the_assignment_operator.html>`_
+   for more information.
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/bitshift.rst b/docs/source/lang/cpp/bitshift.rst
new file mode 100644
index 0000000..e1c8de0
--- /dev/null
+++ b/docs/source/lang/cpp/bitshift.rst
@@ -0,0 +1,144 @@
+.. highlight:: cpp
+
+.. _lang-bitshift:
+
+Bit Shift Operators (``<<``, ``>>``)
+====================================
+
+(Adapted from `The Bit Math Tutorial
+<http://www.arduino.cc/playground/Code/BitMath>`_ in `The Arduino
+Playground <http://www.arduino.cc/playground/Main/HomePage>`_\ )
+
+There are two bit shift operators in C++: the left shift operator
+``<<`` and the right shift operator ``>>``. These operators cause the
+bits in the left operand to be shifted left or right by the number of
+positions specified by the right operand.
+
+More information on bitwise math can be obtained in the Wikipedia
+article on `bitwise operations
+<http://en.wikipedia.org/wiki/Bitwise_operation>`_\ , especially the
+section on shifts in `C, C++, and Java
+<http://en.wikipedia.org/wiki/Bitwise_operation#Shifts_in_C.2C_C.2B.2B.2C_C.23_and_Java>`_\ .
+
+
+Syntax
+------
+
+``some_int << number_of_bits``
+
+``some_int >> number_of_bits``
+
+
+Parameters
+----------
+
+* **some_int** An integer value or variable.
+
+* **number_of_bits** integer whose value is at most ``8 *
+  sizeof(variable)`` (so ``number_of_bits`` can be at most 32 for
+  ``int`` values, at most ``8`` for ``char`` values, etc.; the various
+  integer sizes are summarized :ref:`in this table
+  <lang-arithmetic-int-sizes>`\ ).
+
+
+
+Example:
+--------
+
+Here are some examples of bit shifting, with the binary representation of the number in comments::
+
+    int a = 5;        // binary: 101
+    int b = a << 3;   // binary: 101000, or 40 in decimal
+    int c = b >> 3;   // binary: 101, or back to 5 like we started with
+
+
+When you left shift a value x by y bits (x << y), the leftmost y bits
+in x are lost, literally shifted out of existence.  We'll do this
+example with ``char`` values (which are integers in the range 0-255,
+and take up 8 bits of memory)::
+
+        char a = 5;        // binary (all 8 bits): 00000101
+        char b = a << 7;   // binary:              10000000 - the first 1 in 101 was discarded
+
+
+If you are certain that none of the ones in a value are being shifted
+into oblivion, a simple way to think of the left-shift operator is
+that it multiplies the left operand by 2 raised to the right operand
+power (in math notation, ``x << y`` equals x * 2\ :sup:`y`\ , as long
+as none of the bits of x get shifted out). For example, to generate
+powers of 2, the following expressions can be employed::
+
+        1 <<  0  ==    1
+        1 <<  1  ==    2
+        1 <<  2  ==    4
+        1 <<  3  ==    8
+        ...
+        1 <<  8  ==  256
+        1 <<  9  ==  512
+        1 << 10  == 1024
+        ...
+
+.. _lang-bitshift-signbit-gotcha:
+
+When you shift x right by y bits (``x >> y``), and the highest bit in
+x is a 1, the behavior depends on the exact data type of x. If x is of
+type ``int``, the highest bit is special, and determines whether x is
+negative or not; the details are too complicated to explain here, but
+they are thoroughly explained in the Wikipedia article on `two's
+complement arithmetic
+<http://en.wikipedia.org/wiki/Two%27s_complement>`_\ , which the
+system most computers use to store integers. In that case, the sign
+bit is copied into lower bits, for esoteric historical reasons::
+
+    int x = -16;     // binary (all 32 bits): 11111111111111111111111111110000
+    int y = x >> 3;  // binary:               11111111111111111111111111111110
+
+
+
+This behavior, called "sign extension", is often not what you
+want. You probably wish zeros to be shifted in from the left.  It
+turns out that the right shift rules are different for ``unsigned
+int`` values, so you can use a type cast to suppress ones being copied
+from the left::
+
+    int x = -16;                  // binary: 11111111111111111111111111110000
+    int y = (unsigned int)x >> 3; // binary: 00011111111111111111111111111110
+
+
+
+If you are careful to avoid sign extension, you can use the
+right-shift operator, ``>>``, as a way to divide by powers of 2. For
+example::
+
+   int x = 1000;
+   int y = x >> 3;   // integer division of 1000 by 8, causing y = 125.
+
+
+Arduino Compatibility
+---------------------
+
+Since it's part of the C++ language, bit shifting on the Maple is
+compatible with the Arduino; however, you should keep in mind that the
+Maple has bigger integer types (as in, more bits) than the Arduino.
+
+Since the STM32 is a 32-bit processor, the ``int`` type takes up 32
+bits instead of 16, like on Arduino's 16-bit microcontroller.  This
+means that you can shift left, like ``x << y``, with bigger values of
+``y`` on the Maple before ones in ``x`` start to get shifted out.
+
+To calculate the number of bits of an integer type on the Maple,
+multiply its size in bytes (see :ref:`this table
+<lang-arithmetic-int-sizes>` for these) by 8, since there are 8
+bits in 1 byte.  For example, a ``short`` takes up 2 bytes of memory,
+or 2 * 8 = 16 bits.
+
+See Also
+--------
+
+-  :ref:`lang-bit`
+-  :ref:`lang-bitread`
+-  :ref:`lang-bitwrite`
+-  :ref:`lang-bitclear`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/bitwisemath.rst b/docs/source/lang/cpp/bitwisemath.rst
new file mode 100644
index 0000000..28fe6bf
--- /dev/null
+++ b/docs/source/lang/cpp/bitwisemath.rst
@@ -0,0 +1,186 @@
+.. highlight:: cpp
+
+.. _lang-bitwisemath:
+
+Bitwise Operators (``&``, ``|``, ``^``, ``~``)
+==============================================
+
+The bitwise operators perform their calculations at the bit level of
+variables. They help solve a wide range of common programming
+problems.
+
+Much of the material here is adapted for Maple from an (Arduino)
+`tutorial on bitwise math
+<http://www.arduino.cc/playground/Code/BitMath>`_\ .  Another great
+resource is the Wikipedia article on `bitwise operations
+<http://en.wikipedia.org/wiki/Bitwise_operation>`_\ .
+
+Below are descriptions and syntax for all of the operators.
+
+.. contents:: Contents
+   :local:
+
+.. _lang-bitwisemath-and:
+
+Bitwise AND (``&``)
+-------------------
+
+The bitwise AND operator in C++ is a single ampersand, ``&``, used
+between two other integer expressions. Bitwise AND operates on each
+bit position of the surrounding expressions independently, according
+to this rule: if both input bits are 1, the resulting output is 1,
+otherwise the output is 0. Another way of expressing this is::
+
+        0  0  1  1    operand1
+        0  1  0  1    operand2
+        ----------
+        0  0  0  1    (operand1 & operand2) = result
+
+
+On the Maple, the type ``int`` is a 32-bit value, so using ``&``
+between two ``int`` expressions causes 32 simultaneous AND operations
+to occur. In a code fragment like::
+
+        int a =  92;    // in binary: 00000000000000000000000001011100
+        int b = 101;    // in binary: 00000000000000000000000001100101
+        int c = a & b;  // result:    00000000000000000000000001000100,
+                        //    (or 68 in decimal).
+
+
+Each of the 32 bits in ``a`` and ``b`` are processed using bitwise
+AND, and all 32 resulting bits are stored in ``c``, resulting in the
+value 1000100 in binary, which is 68 in decimal.
+
+
+.. _lang-bitwisemath-or:
+
+Bitwise OR (``|``)
+------------------
+
+The bitwise OR operator in C++ is the vertical bar symbol, ``|``. Like
+the ``&`` operator, ``|`` operates independently on each bit in its
+two surrounding integer expressions, but what it does is
+different. The bitwise OR of two bits is 1 if either or both of the
+input bits is 1, otherwise it is 0.  For example::
+
+        0  0  1  1    operand1
+        0  1  0  1    operand2
+        ----------
+        0  1  1  1    (operand1 | operand2) = result
+
+Here is an example of bitwise OR used in a snippet of C++ code (using
+``char``, which takes up 8 bits of memory, instead of ``int``, which
+uses 32)::
+
+        char a =  92;    // in binary: 01011100
+        char b = 101;    // in binary: 01100101
+        char c = a | b;  // result:    01111101, or 125 in decimal.
+
+.. _lang-bitwisemath-xor:
+
+Bitwise XOR (``^``)
+-------------------
+
+There is a somewhat unusual operator in C++ called bitwise EXCLUSIVE
+OR, also known as bitwise XOR. (In English, this is usually pronounced
+"zor" or "ex-or"). The bitwise XOR operator is written using the caret
+symbol, ``^``. This operator is very similar to the bitwise OR
+operator ``|``, except it evaluates to 0 for a given bit position when
+both of the input bits for that position are 1::
+
+        0  0  1  1    operand1
+        0  1  0  1    operand2
+        ----------
+        0  1  1  0    (operand1 ^ operand2) = result
+
+
+Another way to look at bitwise XOR is that each bit in the result
+is a 1 if the input bits are different, or 0 if they are the same.
+
+Here is a simple example::
+
+        int x = 12;     // binary (ignoring extra bits): 1100
+        int y = 10;     // binary:                       1010
+        int z = x ^ y;  // binary:                       0110, or decimal 6
+
+
+
+The ^ operator is often used to toggle (i.e. change from 0 to 1, or 1
+to 0) some of the bits in an integer expression. In a bitwise OR
+operation if there is a 1 in the mask bit, that bit is inverted; if
+there is a 0, the bit is not inverted and stays the same. Below is a
+program to blink digital pin 13 (the LED pin on Maple)::
+
+    // Blink Maple LED pin
+
+    int led_pin = 13;
+    int toggle = 0;
+
+    // demo for Exclusive OR
+    void setup(){
+        pinMode(led_pin, OUTPUT);
+    }
+
+    void loop(){
+        toggle = toggle ^ 1;
+        digitalWrite(led_pin, toggle);
+        delay(100);
+    }
+
+.. _lang-bitwisemath-not:
+
+Bitwise NOT (``~``)
+-------------------
+
+The bitwise NOT operator in C++ is the tilde character ``~``. Unlike
+``&`` and ``|``, the bitwise NOT operator is applied to a single
+operand to its right. Bitwise NOT changes each bit to its opposite: 0
+becomes 1, and 1 becomes 0. For example::
+
+        0  1    operand1
+        ----
+        1  0   ~operand1 = result
+
+Another example::
+
+        char a = 103;    // binary:  01100111
+        char b = ~a;     // binary:  10011000 = -104
+
+You might be surprised to see a negative number like -104 as the
+result of this operation. This is because the highest bit in an int
+variable is the so-called "sign bit". If the highest bit is 1, the
+number is interpreted as negative. This encoding of positive and
+negative numbers is referred to as *two's complement*. For more
+information, see the Wikipedia article on `two's
+complement. <http://en.wikipedia.org/wiki/Twos_complement>`_
+
+As an aside, it is interesting to note that (under two's complement
+arithmetic) for any integer ``x``, ``~x`` is the same as ``-x-1``.
+
+At times, the sign bit in a signed integer expression can cause
+some unwanted surprises.
+
+
+Uses
+----
+
+One of the most common uses of bitwise operations is to select or
+manipulate a particular bit (or bits) from an integer value, often
+called `bit masking
+<http://en.wikipedia.org/wiki/Mask_%28computing%29>`_\ . See the
+linked Wikipedia article for more information and examples.
+
+If you really want to see bit-twiddling techniques in their full
+glory, you could do much worse than to get yourself a copy of
+`Hacker's Delight <http://www.hackersdelight.org/>`_\ .
+
+
+See Also
+--------
+
+- :ref:`Boolean operations <lang-boolean>` (``&&``, ``||``)
+- :ref:`Compound bitwise operations <lang-compoundbitwise>` (``&=``,
+   ``|=``, ``^=``).
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/boolean.rst b/docs/source/lang/cpp/boolean.rst
new file mode 100644
index 0000000..8d6aa5c
--- /dev/null
+++ b/docs/source/lang/cpp/boolean.rst
@@ -0,0 +1,91 @@
+.. highlight:: cpp
+
+.. _lang-boolean:
+
+Boolean Operators
+=================
+
+These can be used inside the condition of an :ref:`if <lang-if>`
+statement.  Evaluate to :ref:`true <lang-constants-true>` or
+:ref:`false <lang-constants-false>`.
+
+.. contents:: Contents
+   :local:
+
+.. _lang-boolean-and:
+
+&& (logical and)
+----------------
+
+True only if both operands are true.  For example::
+
+    if (digitalRead(2) == HIGH  && digitalRead(3) == HIGH) { // read two switches
+      // ...
+    }
+
+is true only if both inputs are high.  Another example::
+
+    if (a >= 10 && a <= 20){}   // true if a is between 10 and 20
+
+**Be careful** not to say ``10 <= a <= 20``!  This won't work the way
+you want.  You have to separately test whether ``a`` is at least 10
+using ``a >= 10``, then test whether ``a`` is at most 20 using ``a <=
+20``, then combine the results using ``&&``.
+
+
+.. _lang-boolean-or:
+
+\|\| (logical or)
+-----------------
+
+True if either operand is true.  For example::
+
+    if (x > 0 || y > 0) {
+      // ...
+    }
+
+is true if either ``x`` or ``y`` is greater than 0.
+
+.. _lang-boolean-not:
+
+! (logical not)
+---------------
+
+True if the operand is false.  For example::
+
+    if (!x) {
+      // ...
+    }
+
+is true if ``x`` is false (i.e. if ``x`` is zero).
+
+Some Advice
+-----------
+
+.. warning::
+
+   Make sure you don't mistake the boolean AND operator ``&&``
+   (double ampersand) for the :ref:`bitwise AND operator
+   <lang-bitwisemath-and>` ``&`` (single ampersand). They are
+   entirely different beasts.
+
+   Similarly, do not confuse the boolean OR operator ``||`` (double
+   pipe) with the :ref:`bitwise OR operator <lang-bitwisemath-or>`
+   ``|`` (single pipe).
+
+   The :ref:`bitwise NOT operator <lang-bitwisemath-not>` ``~``
+   (tilde) looks much different than the boolean not operator ``!``
+   (exclamation point, or "bang", as some programmers say), but you
+   still have to be sure which one you want.
+
+
+See Also
+--------
+
+- :ref:`Bitwise operators <lang-bitwisemath>` (``&``, ``|``, ``^``, ``~``)
+- :ref:`Compound bitwise operators <lang-compoundbitwise>` (``&=``,
+  ``|=``, ``^=``).
+- :ref:`if statement <lang-if>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/booleanvariables.rst b/docs/source/lang/cpp/booleanvariables.rst
new file mode 100644
index 0000000..6051b8c
--- /dev/null
+++ b/docs/source/lang/cpp/booleanvariables.rst
@@ -0,0 +1,54 @@
+.. highlight:: cpp
+
+.. _lang-booleanvariables:
+
+Booleans
+========
+
+A **boolean** holds one of two values, :ref:`true
+<lang-constants-true>` or :ref:`false <lang-constants-false>`.  On a
+Maple, each boolean variable has type ``bool``.
+
+.. warning::
+
+   On an Arduino, the type ``boolean`` is also provided.  While the
+   Maple also has this type for compatibility, **its use is strongly
+   discouraged**.  The ``bool`` type is a standard part of C++, while
+   ``boolean`` is a non-standard extension that serves no purpose.
+
+Example
+-------
+
+::
+
+    int ledPin = 13;      // LED on pin 13
+    int switchPin = 12;   // momentary switch on 12, other side connected to ground
+
+    // running is a boolean variable:
+    bool running = false;
+
+    void setup() {
+      pinMode(ledPin, OUTPUT);
+      pinMode(switchPin, INPUT);
+      digitalWrite(switchPin, HIGH);      // turn on pullup resistor
+    }
+
+    void loop() {
+      if (digitalRead(switchPin) == LOW) {
+        // switch is pressed - pullup keeps pin high normally
+        delay(100);                        // delay to debounce switch
+        running = !running;                // toggle running variable
+        digitalWrite(ledPin, running)      // indicate via LED
+      }
+    }
+
+See also
+--------
+
+
+-  :ref:`Boolean constants <lang-constants-bool>`
+-  :ref:`Boolean operators <lang-boolean>`
+-  :ref:`Variables <lang-variables>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/break.rst b/docs/source/lang/cpp/break.rst
new file mode 100644
index 0000000..ce8ac17
--- /dev/null
+++ b/docs/source/lang/cpp/break.rst
@@ -0,0 +1,35 @@
+.. highlight:: cpp
+
+.. _lang-break:
+
+``break``
+=========
+
+``break`` is used to exit from a :ref:`while <lang-while>`\ ,
+:ref:`for <lang-for>`\ , or :ref:`do/while <lang-dowhile>` loop,
+bypassing the normal loop condition.  It is also used to exit from a
+:ref:`switch <lang-switchcase>` statement.
+
+
+Example
+-------
+
+::
+
+    for (x = 0; x < 255; x ++)
+    {
+        digitalWrite(PWMpin, x);
+        sens = analogRead(sensorPin);
+        if (sens > threshold){      // bail out on sensor detect
+           x = 0;
+           // this line of code means that we'll immediately exit
+           // from the "for" loop:
+           break;
+        }
+        delay(50);
+    }
+
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/built-in-types.rst b/docs/source/lang/cpp/built-in-types.rst
new file mode 100644
index 0000000..1323db8
--- /dev/null
+++ b/docs/source/lang/cpp/built-in-types.rst
@@ -0,0 +1,95 @@
+.. highlight:: cpp
+
+.. _lang-built-in-types:
+
+================
+ Built-in Types
+================
+
+This document serves as a reference for many of the built-in types
+which are available when programming in the IDE.  Programmers using
+the :ref:`command-line tools <unix-toolchain>` will have access to
+these types as long as they have imported `wirish.h
+<https://github.com/leaflabs/libmaple/blob/master/wirish/wirish.h>`_;
+several are defined in in `libmaple_types.h
+<https://github.com/leaflabs/libmaple/blob/master/libmaple/libmaple_types.h>`_.
+
+.. _lang-built-in-types-integral:
+
+Integral types
+--------------
+
+.. cpp:type:: char
+
+   8-bit integer value.
+
+.. cpp:type:: short
+
+   16-bit integer value.
+
+.. cpp:type:: int
+
+   32-bit integer value.
+
+.. cpp:type:: long
+
+   64-bit integer value.
+
+.. cpp:type:: long long
+
+   64-bit integer value.
+
+.. cpp:type:: int8
+
+   Synonym for ``char``.
+
+.. cpp:type:: uint8
+
+   Synonym for ``unsigned char``.
+
+.. cpp:type:: int16
+
+   Synonym for ``short``.
+
+.. cpp:type:: uint16
+
+   Synonym for ``unsigned short``.
+
+.. cpp:type:: int32
+
+   Synonym for ``int``.
+
+.. cpp:type:: uint32
+
+   Synonym for ``unsigned int``
+
+.. cpp:type:: int64
+
+   Synonym for ``long long``
+
+.. cpp:type:: uint64
+
+   Synonym for ``unsigned long long``.
+
+Floating-Point Types
+--------------------
+
+.. cpp:type:: float
+
+   32-bit, IEEE 754 single-precision floating-point type.
+
+.. cpp:type:: double
+
+   64-bit, IEEE 754 double-precision floating-point type.
+
+Other Types
+-----------
+
+.. cpp:type:: voidFuncPtr
+
+   Pointer to a function that takes no arguments and returns nothing, i.e.
+
+   ::
+
+       typedef void (*voidFuncPtr)(void);
+
diff --git a/docs/source/lang/cpp/byte.rst b/docs/source/lang/cpp/byte.rst
new file mode 100644
index 0000000..45c9d5f
--- /dev/null
+++ b/docs/source/lang/cpp/byte.rst
@@ -0,0 +1,34 @@
+.. highlight:: cpp
+
+.. _lang-byte:
+
+byte
+====
+
+The ``byte`` type stores a 1-byte (8-bit) unsigned integer number,
+from 0 to 255.
+
+.. warning::
+
+   The ``byte`` type is provided for compatibility with Arduino.
+   However, it is a non-standard extension.  The standard C++ type for
+   storing an 8-bit unsigned integer is ``unsigned char``; we
+   recommend using that instead.  (Your code will still work on an
+   Arduino).
+
+
+Example
+-------
+
+::
+
+        byte b = 134;
+
+See Also
+--------
+
+-  :ref:`byte() <lang-bytecast>` (casting a value to a byte)
+-  :ref:`Variables <lang-variables>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/bytecast.rst b/docs/source/lang/cpp/bytecast.rst
new file mode 100644
index 0000000..b3f0de2
--- /dev/null
+++ b/docs/source/lang/cpp/bytecast.rst
@@ -0,0 +1,50 @@
+.. highlight:: cpp
+
+.. _lang-bytecast:
+
+byte() (cast)
+=============
+
+Converts a value to the :ref:`byte <lang-byte>` data type.
+
+.. note::
+
+   Casting to the byte type is provided for compatibility with
+   Arduino.  However, the recommended Maple type for storing an 8-bit
+   unsigned integer is ``uint8``. (C and C++ programmers: ``stdint.h``
+   is also available).
+
+   In order to cast a variable ``x`` to a ``uint8``, the
+   following syntax can be used::
+
+       uint8(x);
+
+Syntax
+------
+
+``byte(x)``
+
+
+Parameters
+----------
+
+**x**: a value of any integer type
+
+
+Returns
+-------
+
+The value, converted to a ``byte``.  Note, however, that if the value
+is larger than the maximum value you can store in a byte (255), then
+the results might be strange and unexpected.
+
+
+See Also
+--------
+
+-  :ref:`lang-byte`
+
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/cc-attribution.txt b/docs/source/lang/cpp/cc-attribution.txt
new file mode 100644
index 0000000..e100140
--- /dev/null
+++ b/docs/source/lang/cpp/cc-attribution.txt
@@ -0,0 +1,9 @@
+.. Included in all this directory's files in order to satisfy the
+.. Arduino CC Attribution-ShareAlike 3.0 License
+
+.. admonition:: License and Attribution
+
+   This documentation page was adapted from the `Arduino Reference
+   Documentation <http://arduino.cc/en/Reference/HomePage>`_\ , which
+   is released under a `Creative Commons Attribution-ShareAlike 3.0
+   License <http://creativecommons.org/licenses/by-sa/3.0/>`_.
diff --git a/docs/source/lang/cpp/char.rst b/docs/source/lang/cpp/char.rst
new file mode 100644
index 0000000..b8747f3
--- /dev/null
+++ b/docs/source/lang/cpp/char.rst
@@ -0,0 +1,50 @@
+.. highlight:: cpp
+
+.. _lang-char:
+
+``char``
+========
+
+The ``char`` type stores a 1-byte character value (or integer with
+value from -128 to 127).  Character literals are written in single
+quotes, like this: ``'A'`` (for multiple characters - strings - use
+double quotes: ``"ABC"``).
+
+
+Just like everything else on a computer, characters are stored as
+numbers. You can see the specific encoding in the `ASCII chart
+<http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters>`_\
+. This means that it is possible to do arithmetic on characters, in
+which the ASCII value of the character is used (e.g. ``'A' + 1`` has the
+decimal value 66, since the ASCII value of the capital letter A in
+decimal is 65).  See the :ref:`Serial.println()
+<lang-serial-println>` documentation for more information about how
+characters are converted into numbers.
+
+The ``char`` datatype is a signed type, meaning that it encodes
+numbers from -128 to 127.  For an unsigned type, which stores values
+from 0 to 255, just use the type ``unsigned char`` (two words).
+
+
+Example
+-------
+
+::
+
+      // the following two lines are equivalent, using the ASCII
+      // character encoding:
+      char c = 'A';
+      char c = 65;
+
+
+See also
+--------
+
+
+- :ref:`lang-int`
+- :ref:`lang-array` (a string is just an array of ``char``\ s)
+- :ref:`Serial.println() <lang-serial-println>`
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/charcast.rst b/docs/source/lang/cpp/charcast.rst
new file mode 100644
index 0000000..a480dec
--- /dev/null
+++ b/docs/source/lang/cpp/charcast.rst
@@ -0,0 +1,36 @@
+.. highlight:: cpp
+
+.. _lang-charcast:
+
+``char()`` (cast)
+=================
+
+Converts a value to the :ref:`char <lang-char>` data type.
+
+Syntax
+------
+
+``char(x)``
+
+
+Parameters
+----------
+
+**x**: a value of any type
+
+
+Returns
+-------
+
+The value, converted to a ``char``.  Note, however, that if the value
+is outside the range of a ``char`` (-128 to 127), then the results
+might be strange and unexpected.
+
+
+See Also
+--------
+
+-  :ref:`char <lang-char>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/comments.rst b/docs/source/lang/cpp/comments.rst
new file mode 100644
index 0000000..c5f118a
--- /dev/null
+++ b/docs/source/lang/cpp/comments.rst
@@ -0,0 +1,67 @@
+.. highlight:: cpp
+
+.. _lang-comments:
+
+Comments
+========
+
+Comments are lines in the program that are used to inform yourself or
+others about the way the program works. They are ignored by the
+compiler, and not exported to the processor, so they don't take up any
+space in RAM or Flash.
+
+One use for comments is to help you understand (or remember) how your
+program works, or to inform others how your program works.  There are
+two different ways of making comments.
+
+.. _lang-comments-singleline:
+
+**Single line comment**: Anything following two slashes, ``//``, until
+the end of the line, is a comment::
+
+     x = 5;  // the rest of this line is a comment
+
+.. _lang-comments-multiline:
+
+**Multi-line comment**: Anything in between a pair of ``/*`` and ``*/``
+is a comment::
+
+    /* <-- a slash-star begins a multi-line comment
+
+    all of this in the multi-line comment - you can use it to comment
+    out whole blocks of code
+
+    if (gwb == 0){   // single line comment is OK inside a multi-line comment
+    x = 3;
+    }
+
+    // don't forget the "closing" star-slash - they have to be balanced:
+    */
+
+Note that it's okay to use single-line comments within a multi-line
+comment, but you can't use multi-line comments within a multi-line
+comment.  Here's an example::
+
+    /* ok, i started a multi-line comment
+
+    x = 3; /* this next star-slash ENDS the multi-line comment: */
+
+    x = 4; // this line is outside of the multi-line comment
+
+    // next line is also outside of the comment, and causes a compile error:
+    */
+
+Programming Tip
+---------------
+
+When experimenting with code, "commenting out" parts of your program
+is a convenient way to remove lines that may be buggy.  This leaves
+the lines in the code, but turns them into comments, so the compiler
+just ignores them. This can be especially useful when trying to locate
+a problem, or when a program refuses to compile and the compiler error
+is cryptic or unhelpful.
+
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/comparison.rst b/docs/source/lang/cpp/comparison.rst
new file mode 100644
index 0000000..b24355f
--- /dev/null
+++ b/docs/source/lang/cpp/comparison.rst
@@ -0,0 +1,87 @@
+.. highlight:: cpp
+
+.. _lang-comparison:
+
+Comparison Operators (``==``, ``!=``, ``<``, ``>``, ``<=``, ``>=``)
+===================================================================
+
+The comparison operators ``==``, ``!=``, ``<``, ``>``, ``<=``, and
+``>=`` are used to compare two numbers.  They are :ref:`true
+<lang-constants-true>` when the comparison is true, and :ref:`false
+<lang-constants-false>` otherwise.  They are based on the symbols
+=, ≠, <, >, ≤, and ≥ from mathematics.
+
+Here are some examples, with their meaning in comments::
+
+     // "eq" is true when x is equal to y
+     bool eq = (x == y);
+
+     // "neq" is true when x is different than y
+     bool neq = (x != y);
+
+     // "lt" is true when x is less than, but NOT equal to, y
+     bool lt = (x <  y);
+
+     // "gt" is true when x is greater than, but NOT equal to, y
+     bool gt = (x >  y);
+
+     // "lte" is true when x is less than or equal to y
+     bool lte = (x <= y);
+
+     // "gte" is true when x is greater than or equal to y
+     bool gte = (x >= y);
+
+The parentheses are optional; they are present only for clarity.  For
+example, the following two lines are the same::
+
+    bool eq = x == y;
+
+    bool eq = (x == y);
+
+Uses
+----
+
+Comparison operators, along with :ref:`boolean operators
+<lang-boolean>`, are useful inside the conditionals of :ref:`if
+<lang-if>` statements.  Here's one example::
+
+    if (x < 50) {
+       // only execute these lines if x is less than 50
+       SerialUSB.println("delaying:");
+       SerialUSB.println(x);
+       delay(x);
+    }
+
+.. warning::
+   Beware of accidentally using the single equal sign (``=``) when you
+   meant to test if two numbers are equal (``==``).  This is a common
+   mistake inside of ``if`` statement conditionals, e.g.::
+
+       // DON'T MAKE THIS MISTAKE
+       if (x = 10) {
+          // body
+       }
+
+   The single equal sign is the assignment operator, and sets x to 10
+   (puts the value 10 into the variable x).  Instead use the double equal
+   sign (e.g. ``if (x == 10)``), which is the comparison operator, and
+   tests *whether* x is equal to 10 or not. The latter statement is only
+   true if x equals 10, but the former statement will always be true.
+
+   This is because C evaluates the statement ``if (x=10)`` as follows: 10
+   is assigned to x (remember that the single equal sign is the
+   :ref:`assignment operator <lang-assignment>`), so x now
+   contains 10. Then the 'if' conditional evaluates 10, which evaluates
+   to :ref:`true <lang-constants-true>`, since any non-zero number
+   evaluates to ``true``.
+
+   Consequently, the conditional of an ``if`` statement like ``if (x =
+   10) {...}`` will always evaluate to ``true``, and the variable x
+   will be set to 10, which is probably not what you meant.
+
+   (This sometimes has uses, though, so just because an assignment
+   appears within a conditional doesn't mean it's automatically wrong.
+   Be careful to know what you mean.)
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/compoundarithmetic.rst b/docs/source/lang/cpp/compoundarithmetic.rst
new file mode 100644
index 0000000..420f1db
--- /dev/null
+++ b/docs/source/lang/cpp/compoundarithmetic.rst
@@ -0,0 +1,44 @@
+.. highlight:: cpp
+
+.. _lang-compoundarithmetic:
+
+Compound Arithmetic Operators (``+=`` , ``-=``, ``*=``, ``/=``)
+===============================================================
+
+These oparators perform a mathematical operation on a variable with
+another constant or variable.  These operators are just a convenient
+shorthand::
+
+    x += y;   // equivalent to the expression x = x + y;
+    x -= y;   // equivalent to the expression x = x - y;
+    x *= y;   // equivalent to the expression x = x * y;
+    x /= y;   // equivalent to the expression x = x / y;
+
+Here is an example::
+
+    int x = 2;
+    int y = 10;
+
+    x += 4;          // x now contains 6
+    x -= 3;          // x now contains 3
+    x *= y;          // x now contains 30
+    x /= 2;          // x now contains 15
+    x += max(20, 6); // x now contains 35
+    x -= sq(5);      // x now contains 15
+
+Parameters
+----------
+
+**x**: a numeric variable
+
+**y**: a numeric variable, number constant, or any other expression
+that evaluates to a number (e.g. call to a function that returns a
+number).
+
+See Also
+--------
+
+- :ref:`Arithmetic operators <lang-arithmetic>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/compoundbitwise.rst b/docs/source/lang/cpp/compoundbitwise.rst
new file mode 100644
index 0000000..a4bbb24
--- /dev/null
+++ b/docs/source/lang/cpp/compoundbitwise.rst
@@ -0,0 +1,231 @@
+.. highlight:: cpp
+
+.. _lang-compoundbitwise:
+
+Compound Bitwise Operators (``&=``, ``|=``, ``^=``)
+===================================================
+
+The compound bitwise operators perform their calculations at the
+bit level of variables. They are often used to clear and set
+specific bits of a variable.
+
+See the :ref:`bitwise math tutorial <lang-bitwisemath>` for more
+information on bitwise operators.
+
+.. contents:: Contents
+   :local:
+
+.. _lang-compoundbitwise-and:
+
+Compound bitwise AND (``&=``)
+-----------------------------
+
+The compound bitwise AND operator ``&=`` is often used with a variable
+and a constant to force particular bits in a variable to be zero. This
+is often referred to in programming guides as "clearing" or
+"resetting" bits.  In a program, writing the line ``x &= y;`` is
+equivalent to writing ``x = x & y;``.  That is, the value of ``x``
+after the line will be equal to its old value bitwise ANDed with the
+value of ``y``::
+
+    x &= y;   // equivalent to x = x & y;
+
+You can use any integer variable for ``x`` (i.e., any variable of type
+``int``, ``long``, ``char``, ``byte``, etc.).  You can use either an
+integer variable or any :ref:`integer value
+<lang-constants-integers>` (like ``3`` or ``0x20``) for ``y``.
+
+Before doing an example of ``&=``, let's first review the Bitwise AND
+(``&``) operator::
+
+       0  0  1  1    operand1
+       0  1  0  1    operand2
+       ----------
+       0  0  0  1    (operand1 & operand2) = result
+
+As shown above, bits that are "bitwise ANDed" with 0 become 0, while
+bits that are "bitwise ANDed" with 1 are left unchanged.  So, if ``b``
+is a ``byte`` variable, then ``b & B00000000`` equals zero, and ``b &
+B11111111`` equals ``b``.
+
+.. _lang-compoundbitwise-binconst:
+
+.. note:: The above uses :ref:`binary constants
+   <lang-constants-integers-bin>`\ .  The numbers are still the same
+   value in other representations, they just might not be as easy to
+   understand.
+
+   Normally, in C and C++ code, :ref:`hexadecimal
+   <lang-constants-integers-hex>` or :ref:`octal
+   <lang-constants-integers-oct>` are used when we're interested in
+   an integer's bits, rather than its value as a number.
+
+   While hexadecimal and octal literals might be harder to understand
+   at first, you should really take the time to learn them.  They're
+   part of C, C++, and many other programming languages, while binary
+   constants are available only for compatibility with Arduino.
+
+   Also, ``B00000000`` is shown for clarity, but zero in any number
+   format is zero.
+
+So, to clear (set to zero) bits 0 and 1 of a one-byte variable, while
+leaving the rest of the variable's bits unchanged, use the compound
+bitwise AND operator ``&=`` with the constant ``B11111100``
+(hexadecimal ``0xFC``\ )::
+
+       1  0  1  0  1  0  1  0    variable
+       1  1  1  1  1  1  0  0    mask
+       ----------------------
+       1  0  1  0  1  0  0  0
+       ^^^^^^^^^^^^^^^^  ^^^^
+          unchanged      cleared
+
+
+Here is the same representation with the variable's bits replaced
+with the symbol ``x``\ ::
+
+       x  x  x  x  x  x  x  x    variable
+       1  1  1  1  1  1  0  0    mask
+       ----------------------
+       x  x  x  x  x  x  0  0
+       ^^^^^^^^^^^^^^^^  ^^^^
+          unchanged       cleared
+
+
+So, using a byte variable ``b``\ , if we say::
+
+    b =  B10101010; // B10101010 == 0xAA
+    b &= B11111100; // B11111100 == 0xFC
+
+then we will have ::
+
+    b == B10101000; // B10101000 == 0xA8
+
+.. _lang-compoundbitwise-or:
+
+Compound bitwise OR (``|=``)
+----------------------------
+
+The compound bitwise OR operator ``|=`` is often used with a variable
+and a constant to "set" (set to 1) particular bits in a variable.  In
+a program, writing the line ``x |= y;`` is equivalent to writing ``x =
+x | y;``.  That is, the value of ``x`` after the line will be equal to
+its old value bitwise ORed with the value of ``y``::
+
+    x |= y;   // equivalent to x = x | y;
+
+You can use any integer variable for ``x`` (i.e., any variable of type
+``int``, ``long``, ``char``, ``byte``, etc.).  You can use either an
+integer variable or any integer value (like ``3`` or ``0x20``) for
+``y``.  (This works the same way as :ref:`compound bitwise AND
+<lang-compoundbitwise-and>`\ , ``&=``).
+
+Before doing an example of ``|=``, let's first review the Bitwise OR
+(``|``) operator::
+
+       0  0  1  1    operand1
+       0  1  0  1    operand2
+       ----------
+       0  1  1  1    (operand1 | operand2) = result
+
+Bits that are "bitwise ORed" with 0 are unchanged, while bits that are
+"bitwise ORed" with 1 are set to 1.  So if ``b`` is a ``byte``
+variable, then ``b | B00000000`` equals ``b``, and ``b & B11111111``
+equals ``B11111111`` (here we've used binary constants; see the
+:ref:`note <lang-compoundbitwise-binconst>` above).
+
+So, to set bits 0 and 1 of a one-byte variable, while leaving the rest
+of the variable unchanged, use the compound bitwise OR operator
+(``|=``) with the constant ``B00000011`` (hexadecimal ``0x3``)::
+
+       1  0  1  0  1  0  1  0    variable
+       0  0  0  0  0  0  1  1    mask
+       ----------------------
+       1  0  1  0  1  0  1  1
+       ^^^^^^^^^^^^^^^^  ^^^^
+           unchanged      set
+
+Here is the same representation with the variable's bits replaced with
+the symbol ``x``::
+
+       x  x  x  x  x  x  x  x    variable
+       0  0  0  0  0  0  1  1    mask
+       ----------------------
+       x  x  x  x  x  x  1  1
+       ^^^^^^^^^^^^^^^^  ^^^^
+           unchanged      set
+
+So, using a byte variable ``b``, if we say::
+
+    b  = B10101010; // B10101010 == 0xAA
+    b |= B00000011; // B00000011 == 0x3
+
+then we will have ::
+
+    b == B10101011; // B10101011 == 0xAB
+
+.. _lang-compoundbitwise-xor:
+
+Compound bitwise XOR (``^=``)
+-----------------------------
+
+The compound bitwise XOR operator ``^=`` is used with a variable and a
+constant to "toggle" (change 0 to 1, and 1 to 0) particular bits in a
+variable.  In a program, writing the line ``x ^= y;`` is equivalent to
+writing ``x = x ^ y;``.  That is, the value of ``x`` after the line
+will be equal to its old value bitwise XORed with the value of ``y``::
+
+    x ^= y;   // equivalent to x = x ^ y;
+
+You can use any integer variable for ``x`` (i.e., any variable of type
+``int``, ``long``, ``char``, ``byte``, etc.).  You can use either an
+integer variable or any integer value (like ``3`` or ``0x20``) for
+``y``.  (This works the same way as :ref:`&=
+<lang-compoundbitwise-and>` and :ref:`\|=
+<lang-compoundbitwise-or>`; in fact, these three operators all
+work the same in this way).
+
+Before doing an example of ``^=``, let's first review the Bitwise
+XOR operator, ``^``::
+
+        0  0  1  1    operand1
+        0  1  0  1    operand2
+        ----------
+        0  1  1  0    (operand1 ^ operand2) = result
+
+One way to look at bitwise XOR is that each bit in the result is a 1
+if the input bits are different, or 0 if they are the same.  Another
+way to think about it is that the result bit will be 1 when *exactly*
+one (no more, no less) of the input bits is 1; otherwise, it will be
+zero.  This means that if you XOR a bit with 1, it will change (or
+toggle) its value, while if you XOR a bit with 0, it stays the same.
+
+So, to toggle bits 0 and 1 of a one-byte variable, while leaving the
+rest of the variable unchanged, use the compound bitwise XOR operator
+``^=`` with the constant ``B00000011`` (hexadecimal ``0x3``\ ; see
+:ref:`note <lang-compoundbitwise-binconst>` above)::
+
+       1  0  1  0  1  0  1  0    variable
+       0  0  0  0  0  0  1  1    mask
+       ----------------------
+       1  0  1  0  1  0  1  1
+       ^^^^^^^^^^^^^^^^  ^^^^
+           unchanged     toggled
+
+So, using a byte variable ``b``, if we say::
+
+    b  = B10101010; // B10101010 == 0xAA
+    b ^= B00000011; // B00000011 == 0x3
+
+then we will have ::
+
+    b == B10101001; // B10101001 == 0xA9
+
+See Also
+--------
+
+- :ref:`Boolean operations <lang-boolean>` (``&&``, ``||``)
+- :ref:`Bitwise operators <lang-bitwisemath>` (``&``, ``|``, ``^``, ``~``)
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/const.rst b/docs/source/lang/cpp/const.rst
new file mode 100644
index 0000000..52de85f
--- /dev/null
+++ b/docs/source/lang/cpp/const.rst
@@ -0,0 +1,52 @@
+.. highlight:: cpp
+
+.. _lang-const:
+
+``const``
+=========
+
+The ``const`` keyword stands for "constant". It is a variable
+*qualifier* that modifies the behavior of the variable, making a
+variable "*read-only*". This means that the variable can be used just
+as any other variable of its type, but its value cannot be
+changed. You will get a compiler error if you try to assign a value to
+a ``const`` variable.
+
+Constants defined with the ``const`` keyword obey the same rules of
+:ref:`variable scoping <lang-scope>` that govern other
+variables. This, and the pitfalls of using :ref:`#define
+<lang-define>`, often makes using the ``const`` keyword a superior
+method for defining constants than ``#define``.
+
+Example
+-------
+
+::
+
+    // this defines a variable called "pi", which cannot be changed:
+    const float pi = 3.14;
+    float x;
+
+    // ....
+
+    x = pi * 2;    // it's fine to find the value of a const variable
+
+    pi = 7;        // illegal - you can't write to (modify) a constant
+
+
+**#define** or **const**
+------------------------
+
+You can use either ``const`` or ``#define`` for creating numeric or
+string constants. For :ref:`arrays <lang-array>`\ , you will need
+to use ``const``. In general, ``const`` is preferred over ``#define``
+for defining constants.
+
+See Also
+--------
+
+-  :ref:`#define <lang-define>`
+-  :ref:`volatile <lang-volatile>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/continue.rst b/docs/source/lang/cpp/continue.rst
new file mode 100644
index 0000000..13d1815
--- /dev/null
+++ b/docs/source/lang/cpp/continue.rst
@@ -0,0 +1,32 @@
+.. highlight:: cpp
+
+.. _lang-continue:
+
+``continue``
+============
+
+The ``continue`` keyword skips the rest of the current iteration of a
+:ref:`while <lang-while>`\ , :ref:`for <lang-for>`\ , or
+:ref:`do/while <lang-dowhile>` loop. It continues by checking the
+conditional expression of the loop, and proceeding with any subsequent
+iterations.
+
+Example
+-------
+
+::
+
+
+    for (x = 0; x < 255; x ++) {
+        if (x > 40 && x < 120) {      // create jump in values
+            continue;   // skips the next two lines and goes to the
+                        // beginning of the loop, with the next value of x
+        }
+
+        digitalWrite(PWMpin, x);
+        delay(50);
+    }
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/curly-braces.rst b/docs/source/lang/cpp/curly-braces.rst
new file mode 100644
index 0000000..a4bd3dc
--- /dev/null
+++ b/docs/source/lang/cpp/curly-braces.rst
@@ -0,0 +1,109 @@
+.. highlight:: cpp
+
+.. _lang-curly-braces:
+
+Curly Braces (``{``, ``}``)
+===========================
+
+.. contents:: Contents
+   :local:
+
+Introduction
+------------
+
+Curly braces (also referred to as just "braces" or as "curly
+brackets") are a major part of the C and C++ programming
+languages. They are used in several different constructs, outlined
+below, and this can sometimes be confusing for beginners.
+
+An opening curly brace, ``{`` must always be followed by a closing
+curly brace ``}``. This is a condition that is often referred to as
+the braces being *balanced*. The Maple IDE (integrated development
+environment) includes a convenient feature to check the balance of
+curly braces. Just select a brace, or even click the insertion point
+immediately following a brace, and its companion will be highlighted\
+[#fbug]_\ .
+
+Beginning programmers, and programmers coming to C++ from languages
+without braces, often find using them confusing or daunting.
+
+Because the use of the curly brace is so varied, it is good
+programming practice to type the closing brace immediately after
+typing the opening brace when inserting a construct which requires
+curly braces. Then insert some blank lines between your braces and
+begin inserting statements. Your braces, and your attitude, will never
+become unbalanced.
+
+Unbalanced braces can often lead to cryptic, impenetrable compiler
+errors that can sometimes be hard to track down in a large program.
+Because of their varied usages, braces are also incredibly important
+to the syntax of a program and moving a brace one or two lines will
+usually dramatically affect the meaning of a program.
+
+The main uses of curly braces
+-----------------------------
+
+**Functions**::
+
+      // a function body needs braces around it
+      void myFunction(datatype argument) {
+        // ... function body goes in here ...
+      }
+
+**Loops** (see the :ref:`while <lang-while>`\ , :ref:`for
+<lang-for>`\ , and :ref:`do/while <lang-dowhile>` loop reference
+pages for more information)::
+
+      // you should put braces around the body of a loop:
+
+      while (boolean expression) {
+         // code inside the loop goes here
+      }
+
+      for (initialisation; termination condition; incrementing expr) {
+         // code inside the loop goes here
+      }
+
+      do {
+         // code inside the loop goes here
+      } while (boolean expression);
+
+
+**Conditional statements** (see the :ref:`if statement <lang-if>`
+reference page for more information)::
+
+      // you should put braces around the body of an "if", "else if",
+      // or "else":
+
+      if (boolean expression) {
+          // code inside the "if"
+      }
+      else if (boolean expression) {
+          // code inside the "else if"
+      }
+      else {
+          // code inside the "else"
+      }
+
+**Switch statements** (see the :ref:`switch statement
+<lang-switchcase>` reference page for more information)::
+
+      switch (var) {
+      case 1:
+          doThing1();
+          break;
+      case 2:
+          doThing2();
+          break;
+      }
+
+.. rubric:: Footnotes
+
+.. TODO remove this once IDE 0.1.0 released
+
+.. [#fbug] At present this feature is slightly buggy as the IDE will
+   often find (incorrectly) a brace in text that has been commented
+   out.
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/define.rst b/docs/source/lang/cpp/define.rst
new file mode 100644
index 0000000..677390d
--- /dev/null
+++ b/docs/source/lang/cpp/define.rst
@@ -0,0 +1,56 @@
+.. highlight:: cpp
+
+.. _lang-define:
+
+``#define``
+===========
+
+``#define`` is a useful C and C++ feature that allows the programmer
+to give a name to a constant value before the program is compiled.
+The compiler will replace references to these constants with the
+defined value at compile time.
+
+This can have some unwanted side effects.  In general, the :ref:`const
+<lang-const>` keyword is preferred for defining constants.
+
+
+Syntax
+------
+
+The following line would define the name ``MY_CONSTANT`` to have value
+``value``::
+
+    #define MY_CONSTANT value
+
+Note that the ``#`` is necessary.  It is usually good style for the
+name to be capitalized, although this is not required.
+
+There is no semicolon after the #define statement. If you include one,
+the compiler will likely throw cryptic errors in unrelated places.
+That is, **don't do this**::
+
+    // DON'T DO THIS! THE SEMICOLON SHOULDN'T BE THERE!
+    #define NAME value;
+
+Similarly, including an equal sign after the ``#define`` line will
+also generate a cryptic compiler error further down the page.  That
+is, **don't do this, either**::
+
+    // DON'T DO THIS, EITHER! THE EQUALS SIGN SHOULDN'T BE THERE!
+    #define NAME = value
+
+Example
+-------
+
+::
+
+    #define LED_PIN 13
+    // The compiler will replace any mention of LED_PIN with
+    // the value 3 at compile time.
+
+See Also
+--------
+-  :ref:`const <lang-const>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/double.rst b/docs/source/lang/cpp/double.rst
new file mode 100644
index 0000000..1527778
--- /dev/null
+++ b/docs/source/lang/cpp/double.rst
@@ -0,0 +1,48 @@
+.. _lang-double:
+
+``double``
+==========
+
+Double precision floating point type. Occupies 8 bytes.  On Maple, the
+``double`` type has a range of approximately -1.79769×10^308 to
+1.79769×10^308; the ``double`` type subject to the same :ref:`overflow
+issues <lang-variables-rollover>` as any numeric data type.
+
+Floating point numbers are not exact, and may yield strange results
+when compared. For example ``6.0 / 3.0`` may not equal ``2.0``. You
+should instead check that the absolute value of the difference between
+the numbers is less than some small number.
+
+Floating point math is also much slower than integer math in
+performing calculations, so should be avoided if, for example, a loop
+has to run at top speed for a critical timing function.  Programmers
+often go to some lengths to convert floating point calculations to
+integer math to increase speed.
+
+For more information, see the `Wikipedia article on floating point
+math <http://en.wikipedia.org/wiki/Floating_point>`_\ .
+
+Floating-point numbers represent numbers with "decimal point", unlike
+integral types, which always represent whole numbers. Floating-point
+numbers are often used to approximate analog and continuous values
+because they have greater resolution than integers.
+
+The double implementation on the Maple uses twice the number of bytes
+as a :ref:`float <lang-float>`, with the corresponding gains in
+precision.
+
+Tip
+---
+
+Users who borrow code from other sources that includes ``double``
+variables may wish to examine the code to see if the implied range and
+precision are different from that actually achieved on the Maple.
+
+See Also
+--------
+
+-  :ref:`float <lang-float>`
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/doublecast.rst b/docs/source/lang/cpp/doublecast.rst
new file mode 100644
index 0000000..511fe24
--- /dev/null
+++ b/docs/source/lang/cpp/doublecast.rst
@@ -0,0 +1,27 @@
+.. highlight:: cpp
+
+.. _lang-doublecast:
+
+``double()`` (cast)
+===================
+
+Converts a value to the :ref:`double <lang-double>` floating point
+data type.  Here is an example::
+
+   int x = 2;
+   double d = double(x);  // d now holds 2.0, a double value
+
+The value ``x`` can be of any type.  However, if ``x`` is not a number
+(like an ``int`` or ``long``), you will get strange results.
+
+See the :ref:`double <lang-double>` reference for details about the
+precision and limitations of ``double`` values on the Maple.
+
+See Also
+--------
+
+-  :ref:`double <lang-double>`
+-  :ref:`float <lang-float>`
+-  :ref:`float() <lang-floatcast>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/dowhile.rst b/docs/source/lang/cpp/dowhile.rst
new file mode 100644
index 0000000..fe92226
--- /dev/null
+++ b/docs/source/lang/cpp/dowhile.rst
@@ -0,0 +1,27 @@
+.. highlight:: cpp
+
+.. _lang-dowhile:
+
+``do``/``while``
+================
+
+A ``do`` loop works in the same manner as a :ref:`while
+<lang-while>` loop, with the exception that the condition is tested
+at the end of the loop, so the ``do`` loop will *always* run at least
+once.
+
+This is the basic syntax::
+
+    do {
+        // statement block
+    } while (test condition);
+
+Example::
+
+    do {
+      delay(50);          // wait for sensors to stabilize
+      x = readSensors();  // check the sensors
+    } while (x < 100);
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/enum.rst b/docs/source/lang/cpp/enum.rst
new file mode 100644
index 0000000..ba82383
--- /dev/null
+++ b/docs/source/lang/cpp/enum.rst
@@ -0,0 +1,53 @@
+.. highlight:: cpp
+
+.. _lang-enum:
+
+``enum``
+========
+
+The ``enum`` keyword is used to specify an enumeration type.  An
+enumeration type is a type whose values are taken from a specified,
+fixed list of constant values.
+
+Example
+-------
+
+Here's an example defining an enumeration type called ``weather``,
+which has values ``HOT``, ``COMFY``, and ``COLD``::
+
+    enum weather {HOT, COMFY, COLD};
+
+Once you've defined this type, you can create variables of type
+``weather``, in the same way you would with an :ref:`int <lang-int>`
+or a :ref:`long <lang-long>`::
+
+    // create a weather variable named theWeather, with value COMFY:
+    weather theWeather = COMFY;
+
+Enumeration types are useful within :ref:`switch statements
+<lang-switchcase>`.  If you know that an argument is of an enumeration
+type, you can make ``case`` statements for all of that type's possible
+values, so you know you won't miss anything::
+
+    void describeWeather(weather currentWeather) {
+        switch(currentWeather) {
+        case HOT:
+            SerialUSB.println("it's hot out");
+            break;
+        case COMFY:
+            SerialUSB.println("it's nice today");
+            break;
+        case COLD:
+            SerialUSB.println("it's freezing!");
+            break;
+        }
+    }
+
+Such a ``switch`` statement would need no :ref:`default
+<lang-switchcase-default>`, since we know that ``currentWeather`` must
+be either ``HOT``, ``COMFY``, or ``COLD``.
+
+See Also
+--------
+
+- :ref:`lang-switchcase`
diff --git a/docs/source/lang/cpp/float.rst b/docs/source/lang/cpp/float.rst
new file mode 100644
index 0000000..6937c8c
--- /dev/null
+++ b/docs/source/lang/cpp/float.rst
@@ -0,0 +1,50 @@
+.. highlight:: cpp
+
+.. _lang-float:
+
+``float``
+=========
+
+Single-precision floating point number. Occupies 4 bytes. On Maple,
+the ``float`` type has a range of approximately -3.40282×10^38 to
+3.40282×10^38; the ``float`` type is subject to the same
+:ref:`overflow issues <lang-variables-rollover>` as any numeric data
+type.
+
+``float``\ s have only 6-7 decimal digits of precision. That means the
+total number of digits, not the number to the right of the decimal
+point.  You can get more precision by using a :ref:`double
+<lang-double>` (which has a precision of about 16 decimal digits).
+
+The following example declares a ``float`` value named ``myfloat``::
+
+        float myfloat;
+
+This example declares a ``float`` value named ``sensorCalibrate``,
+with value 1.117::
+
+        float sensorCalibrate = 1.117;
+
+The general syntax for declaring a float named ``var`` with value
+``val`` is::
+
+        float var = val;
+
+Here is a more extended example involving a :ref:`float cast
+<lang-floatcast>`::
+
+       int x;
+       int y;
+       float z;
+
+       x = 1;
+       y = x / 2;          // y now contains 0, ints can't hold fractions
+       z = float(x) / 2; // z now contains .5
+
+See Also
+--------
+
+-  :ref:`double <lang-double>`
+-  :ref:`Variables <lang-variables>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/floatcast.rst b/docs/source/lang/cpp/floatcast.rst
new file mode 100644
index 0000000..4766478
--- /dev/null
+++ b/docs/source/lang/cpp/floatcast.rst
@@ -0,0 +1,28 @@
+.. highlight:: cpp
+
+.. _lang-floatcast:
+
+``float()`` (cast)
+==================
+
+Converts a value to the :ref:`float <lang-float>` data type.  Here is
+an example (see the :ref:`constants reference <lang-constants-fp>` for
+an explanation of the "2.0f")::
+
+   int x = 2;
+   float f = float(x);  // f now holds 2.0f, a float value
+
+The value ``x`` can be of any type.  However, if ``x`` is not a number
+(like an ``int``), you will get strange results.
+
+See the :ref:`float <lang-float>` reference for details about the
+precision and limitations of ``float`` values on the Maple.
+
+See Also
+--------
+
+-  :ref:`float <lang-float>`
+-  :ref:`double <lang-double>`
+-  :ref:`double() <lang-doublecast>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/for.rst b/docs/source/lang/cpp/for.rst
new file mode 100644
index 0000000..71c5aca
--- /dev/null
+++ b/docs/source/lang/cpp/for.rst
@@ -0,0 +1,142 @@
+.. highlight:: cpp
+
+.. _lang-for:
+
+``for``
+=======
+
+A ``for`` loop is used to repeat a block of statements enclosed in
+curly braces.  ``for`` loops are useful for performing repetitive
+operations, and are often used in combination with :ref:`arrays
+<lang-array>` to operate on collections of data or multiple
+:ref:`pins <gpio>`.  A ``for`` loop is composed of two parts: first, a
+*header*, which sets up the for loop, and then a *body*, which is made
+up of lines of code enclosed in curly braces.
+
+.. contents:: Contents
+   :local:
+
+Syntax
+------
+
+There are three parts to the ``for`` loop header: an *initialization*
+expression, *loop condition* expression, and a *post-loop*
+expression.  The general syntax looks like this::
+
+    for (initialization; condition; post-loop) {
+        // all of these lines inside the curly braces are part
+        // of the loop body.
+        statement 1;
+        statement 2;
+        ...
+    }
+
+(Note that there is no semicolon after the post-loop).  The
+initialization happens first and exactly once, before the loop begins.
+Each time through the loop, the condition is tested.  The condition is
+a :ref:`boolean <lang-boolean>` expression.  If it is true, then the
+list of statements inside the curly braces are executed.  Next, the
+post-loop is executed.  The loop then begins again by evaluating the
+condition again, entering the loop body if it is true.  This proceeds
+until the condition becomes false.
+
+Examples
+--------
+
+Here's an example::
+
+    // Dim an LED using a PWM pin
+    int pwmPin = 9; // LED in series with 470 ohm resistor on pin 9
+
+    void setup() {
+       pinMode(pwmPin, PWM);
+    }
+
+    void loop() {
+       for (int i=0; i <= 65535; i++) {
+          pwmWrite(pwmPin, i);
+          delay(1);
+       }
+    }
+
+There is a ``for`` loop In the :ref:`loop() <lang-loop>` function of
+the above example.  This loop starts by declaring an ``int`` variable
+named ``i``, whose value starts out at zero.  The loop proceeds by
+checking if ``i`` is less than or equal to 65535.  Since ``i`` is
+zero, this is true, and so the calls to :ref:`pwmWrite()
+<lang-pwmwrite>` and :ref:`delay() <lang-delay>` happen next.  At this
+point, the post-loop expression ``i++`` is evaluated, which
+:ref:`increments <lang-increment>` ``i``, so that ``i`` becomes one.
+That concludes the first time through the loop.  Each "time through
+the loop" is referred to as an *iteration*.
+
+The loop then jumps back to the beginning, checking the condition as
+the beginning of its second iteration (initialization is skipped,
+since this only happens once, before the first iteration).  One is
+less than 65535, so the loop statements are executed again.  This
+proceeds over and over until the iteration when ``i`` finally
+reaches 65536.  At that point, the condition is no longer true, so the
+loop stops executing, and the ``loop()`` function returns.
+
+Here's another example, using a ``for`` loop to brighten and fade an
+LED (see the :ref:`pwmWrite() <lang-pwmwrite>` reference for more
+information)::
+
+    int pwmPin = 9; // hook up the LED to pin 9
+    void loop() {
+       int x = 1;
+       for (int i = 0; i >= 0; i += x) {
+          analogWrite(pwmPin, i); // controls the brightness of the LED
+          if (i == 65535) {
+              x = -1;             // switch direction, so i starts decreasing
+          }
+          delay(1);
+       }
+    }
+
+Coding Tips
+-----------
+
+The C ``for`` loop is more flexible than ``for`` loops found in some
+other computer languages, including BASIC.  Any or all of the three
+header elements may be left blank, although the semicolons are
+required. Also the statements for initialization, condition, and
+post-loop can be any valid C statements, and use any C datatypes,
+including :ref:`floating point numbers <lang-double>`. These types
+of unusual ``for`` loops sometimes provide solutions to less-common
+programming problems.
+
+For example, using a multiplication in the post-loop line will
+generate a `geometric progression
+<http://en.wikipedia.org/wiki/Geometric_progression>`_::
+
+    for(int x = 1; x <= 100; x = x * 2) {
+        SerialUSB.println(x);
+    }
+
+
+This loop prints out the numbers 1, 2, 4, 8, ..., 64.  Check
+your understanding of ``for`` loops by answering the following two
+questions (answers are in footnote [#fanswers]_\ ):
+
+1. How many iterations occur before the loop finishes?
+
+2. Why does it stop at 64?
+
+See also
+--------
+
+- :ref:`while <lang-while>` loops
+- :ref:`do <lang-dowhile>` loops
+
+.. rubric:: Footnotes
+
+.. [#fanswers]
+   1. Seven.
+
+   2. After the seventh iteration, the post-loop causes ``x`` to
+      equal 128.  This is larger than 100, so the loop condition is
+      false, and the loop stops.
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/goto.rst b/docs/source/lang/cpp/goto.rst
new file mode 100644
index 0000000..ff2f248
--- /dev/null
+++ b/docs/source/lang/cpp/goto.rst
@@ -0,0 +1,130 @@
+.. highlight:: cpp
+
+.. _lang-goto:
+
+Labels and ``goto``
+===================
+
+A *label* gives a name to a line of code within a function.  You can
+label a line by writing a name for it, then a colon (``:``), before
+the line starts.  The ``goto`` keyword allows program flow to transfer
+to a labeled line from anywhere within the same function.
+
+.. warning:: The use of ``goto`` is discouraged in C and C++
+   programming.  It is *never necessary* to use ``goto`` to write a
+   program.
+
+   Unless you know what you're doing, using ``goto`` tends to
+   encourage code which is harder to debug and understand than
+   programs without ``goto`` that do the same thing.  That said,
+   however, it's sometimes useful; :ref:`see below <goto-when-to-use>`
+   for a concrete example.
+
+Using Labels and goto
+---------------------
+
+Labels and ``goto`` are probably best explained through example.
+Let's start with an example of how to label lines.  The first line
+(``int x = analogRead(some_pin);``) in the :ref:`loop <lang-loop>`
+function below has label ``readpin``.  The third line (``delay(x);``)
+has label ``startdelay``.  The second line (``SerialUSB.println(x);``)
+does not have a label::
+
+       void loop() {
+       readpin:
+              int x = analogRead(some_pin);
+              SerialUSB.println(x); // for debugging
+       startdelay:
+              delay(x);
+              // ... more code ...
+       }
+
+Anything which can be a :ref:`variable <lang-variables>` name can
+be a label.
+
+Let's say that we wanted to print ``x`` only if it was very large, say
+at least 2000.  We might want to do this just so anybody watching on a
+:ref:`serial monitor <ide-serial-monitor>` would know they were in for
+a longer wait than usual.  We can accomplish this through the use of a
+``goto`` statement that skips the printing if ``x`` is less than
+2000::
+
+       void loop() {
+       readpin:
+              int x = analogRead(some_pin);
+              if (x < 2000) {
+                  goto startdelay;
+              }
+              SerialUSB.println(x); // for debugging
+       startdelay:
+              delay(x);
+              // ... more code ...
+       }
+
+In this modified program, whenever ``x`` is less than 2000, the body
+of the :ref:`if <lang-if>` statement in the second line is
+executed.  The ``goto`` statement inside the ``if`` body skips
+straight to the line labeled ``startdelay``, passing over the line
+doing the printing.
+
+A ``goto`` does not have to "move forwards"; it can go "backwards",
+too.  For example, the following program prints "5" forever (why?)::
+
+    void loop() {
+    printfive:
+        SerialUSB.println(5);
+        goto printfive;
+        SerialUSB.println(6);
+    }
+
+.. _goto-when-to-use:
+
+When to Use goto
+----------------
+
+As mentioned above, use of ``goto`` is `generally discouraged
+<http://en.wikipedia.org/wiki/Goto#Criticism_and_decline>`_.  However,
+when used with care, ``goto`` can simplify certain programs.  One
+important use case for ``goto`` is breaking out of deeply nested
+:ref:`for <lang-for>` loops or :ref:`if <lang-if>` logic blocks.
+Here's an example::
+
+    for(int r = 0; r < 255; r++) {
+        for(int g = 255; g > -1; g--) {
+            for(int b = 0; b < 255; b++) {
+                if (analogRead(0) > 250) {
+                    goto bailout;
+                }
+                // more statements ...
+            }
+            // innermost loop ends here
+        }
+    }
+    bailout:
+    // more code here
+
+In the above example, whenever the :ref:`analog reading
+<lang-analogread>` on pin 0 was greater than 250, the program would
+jump to the line labeled ``bailout``, exiting all three loops at once.
+
+While there is already a :ref:`break <lang-break>` keyword for
+breaking out of a loop, it will only break out of the *innermost*
+loop.  So, if instead of saying "``goto bailout;``", there was a
+"``break;``" instead, the program would only exit from the loop with
+header "``for(int b = 0; b < 255; b++)``".  The program would continue
+at the line which reads "``// innermost loop ends here``", which is
+clearly undesirable if you wanted to leave all three loops at once.
+
+More examples of when ``goto`` is a good choice are given in Donald
+Knuth's paper, "Structured Programming with go to Statements"; see
+below for a link.
+
+See Also
+--------
+
+- Dijkstra, Edsger W. `Go To Statement Considered Harmful <http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.92.4846&rep=rep1&type=pdf>`_ (PDF)
+
+- Knuth, Donald. `Structured Programming with go to Statements <http://pplab.snu.ac.kr/courses/adv_pl05/papers/p261-knuth.pdf>`_ (PDF)
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/if.rst b/docs/source/lang/cpp/if.rst
new file mode 100644
index 0000000..bef89e2
--- /dev/null
+++ b/docs/source/lang/cpp/if.rst
@@ -0,0 +1,121 @@
+.. highlight:: cpp
+
+.. _lang-if:
+
+``if``/``else``
+===============
+
+An ``if`` statement is used to execute code when certain conditions
+are met.  The general syntax for an ``if`` statement is::
+
+    if (condition) {
+        body
+    }
+
+An ``if`` statement first tests whether its *condition* is true (such
+as an input being above a certain number).  If the condition is true,
+the ``if`` statement executes its *body*, which is made up of lines of
+code inside :ref:`curly braces <lang-curly-braces>`.  If the condition
+is false, the body is not executed.  Here's a more concrete example::
+
+    if (someVariable > 50) {
+      // do something here
+    }
+
+The program tests to see if ``someVariable`` is greater than 50. If it
+is, the program executes every line in the curly braces (which in the
+above example does nothing, since the body is just the :ref:`comment
+<lang-comments>` line "``// do something here``").
+
+Put another way, if the statement in parentheses is true, the
+statements inside the braces are run. If not, the program skips over
+the code.
+
+An ``if`` statement's condition (which is inside the parentheses after
+``if``) often uses one or more :ref:`boolean <lang-boolean>` or
+:ref:`comparison <lang-comparison>` operators.
+
+Writing the if Body
+-------------------
+
+The brackets may be omitted after an ``if`` statement's
+conditional. If this is done, the next line (which ends in a
+semicolon) becomes the only line in the body.  The following three
+``if`` statements all do the same thing::
+
+    if (x > 120) digitalWrite(ledPin, HIGH);
+
+    if (x > 120)
+        digitalWrite(ledPin, HIGH);
+
+    if (x > 120) {
+        digitalWrite(ledPin, HIGH);
+    }
+
+However, the following two examples are different::
+
+    // example 1: two lines of code in the if body
+    if (x > 120) {
+      digitalWrite(ledPin1, HIGH);
+      digitalWrite(ledPin2, HIGH);
+    }
+
+    // example 2: one line of code in the if body, and
+    // another line of code after the if statement
+    if (x > 120)
+      digitalWrite(ledPin1, HIGH); // this is in the if body
+      digitalWrite(ledPin2, HIGH); // this is NOT in the if body
+
+In the first example, since the body is enclosed in curly braces, both
+lines are included.  In the second example, since the curly braces are
+missing, only the first line is in the ``if`` body.
+
+``else``
+--------
+
+``if``/\ ``else`` allows greater control over the flow of code than
+the basic :ref:`if <lang-if>` statement, by allowing multiple tests to
+be grouped together. For example, an :ref:`analog input
+<lang-analogread>` could be tested, with one action taken if the input
+was less than 500, and another action taken if the input was 500 or
+greater. The code would look like this::
+
+    if (pinFiveInput < 500) {
+      // action A
+    } else {
+      // action B
+    }
+
+``else`` can precede another ``if`` test, so that multiple, mutually
+exclusive tests can be run at the same time.
+
+Each test will proceed to the next one until a true test is
+encountered. When a true test is found, its associated block of code
+is run, and the program then skips to the line following the entire
+if/else construction. If no test proves to be true, the default
+``else`` block is executed, if one is present, and sets the default
+behavior.
+
+Note that an ``else if`` block may be used with or without a
+terminating ``else`` block, and vice-versa. An unlimited number of
+such ``else if`` branches is allowed.  Here is a code example::
+
+    if (pinFiveInput < 500) {
+      // do Thing A
+    } else if (pinFiveInput >= 1000) {
+      // do Thing B
+    } else {
+      // do Thing C
+    }
+
+Another way to express branching, mutually exclusive tests, is with a
+:ref:`switch/case <lang-switchcase>` statement.
+
+
+See Also
+--------
+
+- :ref:`boolean operators <lang-boolean>`
+- :ref:`comparison operators <lang-comparison>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/include.rst b/docs/source/lang/cpp/include.rst
new file mode 100644
index 0000000..74fe7af
--- /dev/null
+++ b/docs/source/lang/cpp/include.rst
@@ -0,0 +1,72 @@
+.. highlight:: cpp
+
+.. _lang-include:
+
+``#include``
+============
+
+``#include`` is used to include outside libraries in your sketch.
+This gives the programmer access to a large group of standard C
+libraries (groups of pre-made functions and data types), and also
+libraries written especially for Maple.
+
+Example
+-------
+
+This example (from the `Arduino LiquidCrystal Tutorial
+<http://arduino.cc/en/Tutorial/LiquidCrystal>`_) includes a library
+that is used to control :ref:`LCD displays
+<libraries-liquid-crystal>`::
+
+    // include the library code:
+    #include <LiquidCrystal.h>
+
+    // initialize the library with the numbers of the interface pins
+    LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
+
+    void setup() {
+      // set up the LCD's number of columns and rows:
+      lcd.begin(16, 2);
+      // Print a message to the LCD.
+      lcd.print("hello, world!");
+    }
+
+    void loop() {
+      // set the cursor to column 0, line 1
+      // (note: line 1 is the second row, since counting begins with 0):
+      lcd.setCursor(0, 1);
+      // print the number of seconds since reset:
+      lcd.print(millis()/1000);
+    }
+
+Note that a ``#include`` line, like :ref:`#define <lang-define>`,
+has **no semicolon**.  The compiler will print strange error messages
+if you add one.
+
+C Standard Library
+------------------
+
+The standard C library that comes with Maple is called `newlib
+<http://sourceware.org/newlib/>`_.  Its main sources of documentation
+are its `main reference <http://sourceware.org/newlib/libc.html>`_
+page and its `math functions
+<http://sourceware.org/newlib/libm.html>`_ reference page.  Here's an
+example that imports the math.h library in order to take the `cube
+root <http://en.wikipedia.org/wiki/Cube_root>`_ of a number::
+
+    #include <math.h>
+
+    void setup() {
+        // no setup necessary
+    }
+
+    void loop() {
+        // "cbrt" stands for "cube root"
+        double cubeRootOf3 = cbrt(3.0);
+        // prints a number that is approximately the cube root of 3:
+        SerialUSB.println(cubeRootOf3);
+    }
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/increment.rst b/docs/source/lang/cpp/increment.rst
new file mode 100644
index 0000000..6dffa80
--- /dev/null
+++ b/docs/source/lang/cpp/increment.rst
@@ -0,0 +1,37 @@
+.. highlight:: cpp
+
+.. _lang-increment:
+
+Increment and Decrement Operators (``++``, ``--``)
+==================================================
+
+These operators increment (add one to) or decrement (subtract one
+from) a variable.  If they come before the variable, they return its
+new value; otherwise, they return its old value.
+
+Some quick examples::
+
+    x++;  // adds one to x, and returns the old value of x
+    ++x;  // adds one to x, and returns the new value of x
+
+    x--;   // decrement x by one and returns the old value of x
+    --x;   // decrement x by one and returns the new value of x
+
+A more extended example::
+
+    x = 2;
+    y = ++x;      // x now contains 3, y contains 3
+    y = x--;      // x contains 2 again, y still contains 3
+
+.. warning:: Be careful!  You cannot put a space in between the two
+    ``+`` or ``-`` signs.  This example is broken::
+
+        // this line won't compile (notice the extra space):
+        int y = x+ +;
+
+See Also
+--------
+
+- :ref:`lang-compoundarithmetic`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/int.rst b/docs/source/lang/cpp/int.rst
new file mode 100644
index 0000000..ca75f75
--- /dev/null
+++ b/docs/source/lang/cpp/int.rst
@@ -0,0 +1,64 @@
+.. highlight:: cpp
+
+.. _lang-int:
+
+``int``
+=======
+
+The ``int`` data type represents integers.  Integers are your primary
+data type for number storage, and store a 4 byte value. This yields a
+range of -2,147,483,648 to 2,147,483,647 (minimum value of -2^31 and a
+maximum value of (2^31) - 1; that's about negative 2 billion to
+positive 2 billion).
+
+An ``int`` stores a negative number with a technique called `two's
+complement math
+<http://en.wikipedia.org/wiki/Two%27s_complement#Explanation>`_\ .
+The highest bit in an ``int``, sometimes refered to as the "sign" bit,
+flags the number as a negative number.  (See the linked article on
+two's complement for more information).
+
+The Maple takes care of dealing with negative numbers for you, so that
+arithmetic operations work mostly as you'd expect. There can be an
+:ref:`unexpected complication <lang-bitshift-signbit-gotcha>` in
+dealing with the :ref:`bitshift right operator (>>)
+<lang-bitshift>`, however.
+
+Here is an example of declaring an ``int`` variable named ``ledPin``,
+then giving it value 13::
+
+    int ledPin = 13;
+
+The general syntax for declaring an ``int`` variable named ``var``,
+then giving it value ``val``, looks like::
+
+    int var = val;
+
+.. _lang-int-overflow:
+
+Integer Overflow
+----------------
+
+When ``int`` variables leave the range specified above, they
+:ref:`roll over <lang-variables-rollover>` in the other direction.
+Here are some examples::
+
+       int x;
+       x = -2,147,483,648;
+       x--; // x now contains 2,147,483,647; rolled over "left to right"
+
+       x = 2,147,483,647;
+       x++; // x now contains -2,147,483,648; rolled over "right to left"
+
+See Also
+--------
+
+-  :ref:`unsigned int <lang-unsignedint>`
+-  :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
diff --git a/docs/source/lang/cpp/intcast.rst b/docs/source/lang/cpp/intcast.rst
new file mode 100644
index 0000000..386fe14
--- /dev/null
+++ b/docs/source/lang/cpp/intcast.rst
@@ -0,0 +1,29 @@
+.. highlight:: cpp
+
+.. _lang-intcast:
+
+``int()`` (cast)
+================
+
+Converts a value to the :ref:`int <lang-int>` data type.  Here is
+an example::
+
+    double d = 2.5;
+    int i = int(d); // i holds "2", an int value
+
+The value inside of the parentheses (``int(...)``) can be of any type.
+However, if it is not a numeric type (like ``double``, ``char``,
+etc.), you will get strange results.
+
+See the :ref:`int <lang-int>` reference for details about the
+precision and limitations of ``int`` variables on the Maple.
+
+See Also
+--------
+
+-  :ref:`int <lang-int>`
+
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/keywords.rst b/docs/source/lang/cpp/keywords.rst
new file mode 100644
index 0000000..e3bc20d
--- /dev/null
+++ b/docs/source/lang/cpp/keywords.rst
@@ -0,0 +1,205 @@
+.. _lang-keywords:
+
+Keywords
+========
+
+This page lists all of the C++ keywords, and either links to a
+reference page explaining their use, or provides a brief description.
+
+List of Keywords
+----------------
+
+The C++ keywords are:
+
+``and``, ``and_eq``, ``asm``, ``auto``, ``bitand``, ``bitor``,
+``bool``, ``break``, ``case``, ``catch``, ``char``, ``class``,
+``compl``, ``const``, ``const_cast``, ``continue``, ``default``,
+``delete``, ``do``, ``double``, ``dynamic_cast``, ``else``, ``enum``,
+``explicit``, ``export``, ``extern``, ``false``, ``float``, ``for``,
+``friend``, ``goto``, ``if``, ``inline``, ``int``, ``long``,
+``mutable``, ``namespace``, ``new``, ``not``, ``not_eq``,
+``operator``, ``or``, ``or_eq``, ``private``, ``protected``,
+``public``, ``register``, ``reinterpret_cast``, ``return``, ``short``,
+``signed``, ``sizeof``, ``static``, ``static_cast``, ``struct``,
+``switch``, ``template``, ``this``, ``throw``, ``true``, ``try``,
+``typedef``, ``typeid``, ``typename``, ``union``, ``unsigned``,
+``using``, ``virtual``, ``void``, ``volatile``, ``wchar_t``,
+``while``, ``xor``, ``xor_eq``
+
+Boolean Operator Synonyms
+-------------------------
+
+- ``and`` is a synonym for :ref:`&& <lang-boolean-and>`.
+- ``not`` is a synonym for :ref:`\! <lang-boolean-not>`.
+- ``not_eq`` is a synonym for :ref:`\!= <lang-comparison>`.
+- ``or`` is a synonym for :ref:`|| <lang-boolean-or>`.
+
+Bitwise Operator Synonyms
+-------------------------
+
+- ``and_eq`` is a synonym for :ref:`&= <lang-compoundbitwise-and>`.
+- ``bitand`` is a synonym for (bitwise) :ref:`& <lang-bitwisemath-and>`.
+- ``bitor`` is a synonym for :ref:`\| <lang-bitwisemath-or>`.
+- ``compl`` is a synonym for :ref:`~ <lang-bitwisemath-not>`.
+- ``or_eq`` is a synonym for :ref:`|= <lang-compoundbitwise-or>`.
+- ``xor`` is a synonym for :ref:`^ <lang-bitwisemath-xor>`.
+- ``xor_eq`` is a synonym for :ref:`^= <lang-compoundbitwise-xor>`.
+
+Constants
+---------
+
+- ``true`` and ``false`` are the :ref:`boolean constants
+  <lang-booleanvariables>`.
+
+Control Flow
+------------
+
+- ``break`` can exit out of a :ref:`switch statement
+  <lang-switchcase>` or a :ref:`for <lang-for>`, :ref:`do
+  <lang-dowhile>`, or :ref:`while <lang-while>` loop.
+
+- ``case`` defines alternatives in a :ref:`switch statement <lang-switchcase>`.
+
+- ``continue`` will move control flow to the next iteration of the
+  enclosing :ref:`for <lang-for>`, :ref:`do <lang-dowhile>`, or
+  :ref:`while <lang-while>` loop.
+
+- ``default`` defines the default alternative in a :ref:`switch
+  statement <lang-switchcase>`.
+
+- ``do`` introduces a :ref:`do <lang-dowhile>` loop.
+
+- ``else`` is used in :ref:`if statements <lang-if>`.
+
+- ``for`` introduces a :ref:`for <lang-for>` loop.
+
+- ``goto`` :ref:`jumps <lang-goto>` to a label.
+
+- ``if`` introduces an :ref:`if statement <lang-if>`.
+
+- ``return`` :ref:`transfers flow to a function's caller <lang-return>`.
+
+- ``switch`` introduces a :ref:`switch statement <lang-switchcase>`.
+
+- ``while`` introduces a :ref:`while <lang-while>` loop.
+
+Types
+-----
+
+The following keywords are used for built-in types.
+
+- :ref:`bool <lang-booleanvariables>`
+- :ref:`lang-char`
+- :ref:`lang-double`
+- :ref:`lang-float`
+- :ref:`lang-int`
+- :ref:`lang-long`
+- :ref:`short <lang-built-in-types-integral>`
+- :ref:`void <lang-void>` (not really a type, but used in the absence
+  of one)
+
+The following keywords are used to introduce new types.
+
+- :ref:`enum <lang-enum>`
+
+Qualifiers
+----------
+
+- :ref:`static <lang-static>` can be used to declare persistent local
+  variables; it has other uses not documented here.
+
+- ``unsigned`` is used to specify an unsigned integral type.
+  Examples: :ref:`lang-unsignedint`, :ref:`lang-unsignedchar`,
+  :ref:`lang-unsignedlong`.
+
+- :ref:`volatile <lang-volatile>` is useful when declaring variables
+  that may be modified by external interrupts.
+
+- :ref:`const <lang-const>` is used to define constants.
+
+Other
+-----
+
+These keywords are not described in the Maple documentation.  For more
+information, consult a C++ reference.
+
+- ``asm`` is used to insert literal assembly language.
+
+- ``auto`` is used to declare that a variable has automatic storage.
+
+- ``catch`` is used in exception handling.  Note that the default
+  flags we pass to :ref:`GCC <arm-gcc>` include ``-fno-exceptions``.
+
+- ``class`` is used to define classes.
+
+- ``const_cast`` is used in typecasting.
+
+- ``delete`` is used to free ``new``\ -allocated storage.  Note that
+  dynamic memory allocation is not available by default on the Maple,
+  so you'll have to bring your own ``new`` and ``delete`` if you want
+  this.
+
+- ``dynamic_cast`` is used in typecasting.
+
+- ``explicit`` is used to declare constructors that can be called only
+  explicitly.
+
+- ``export`` declares a template definition accessible to other
+  compilation units.
+
+- ``extern`` can mark a declaration as a declaration and not a
+  definition, and also grant external linkage to a ``const`` or
+  ``typedef``.
+
+- ``friend`` is used to declare that certain functions have access to
+  a class's private variables.
+
+- ``inline`` is a compiler hint to inline a function.
+
+- ``mutable`` specifies that a member can be updated, even when a
+  member of a ``const`` object.
+
+- ``namespace`` declares a new namespace.
+
+- ``new`` dynamically allocates space for a value.  Note that dynamic
+  memory allocation is not available by default on the Maple, so
+  you'll have to bring your own ``new`` and ``delete`` if you want
+  this.
+
+- ``operator`` is used to define type-specific operator overrides.
+
+- ``private`` declares a private class member.
+
+- ``protected`` declares a protected class member.
+
+- ``public`` declares a public class member.
+
+- ``register`` is a compiler hint to store a variable in a register.
+
+- ``reinterpret_cast`` is used in typecasting.
+
+- ``signed`` is the opposite of ``unsigned``.
+
+- ``static_cast`` is used in typecasting.
+
+- ``struct`` declares a new struct.
+
+- ``template`` introduces a template class, function, etc.
+
+- ``this`` is a pointer to the receiver object.
+
+- ``throw`` is used in exception handling.  Note that the default
+  flags we pass to :ref:`GCC <arm-gcc>` include ``-fno-exceptions``.
+
+- ``try`` is used in exception handling.  Note that the default
+  flags we pass to :ref:`GCC <arm-gcc>` include ``-fno-exceptions``.
+
+- ``typedef`` defines a type synonym.
+
+- ``union`` defines an untagged union.
+
+- ``using`` is a directive related to namespaces.
+
+- ``virtual`` declares a method which may be overridden.
+
+- ``wchar_t`` is the wide character type.
diff --git a/docs/source/lang/cpp/long.rst b/docs/source/lang/cpp/long.rst
new file mode 100644
index 0000000..d8498c0
--- /dev/null
+++ b/docs/source/lang/cpp/long.rst
@@ -0,0 +1,52 @@
+.. highlight:: cpp
+
+.. _lang-long:
+
+``long``
+========
+
+The ``long`` data type stores extended size integer values.  You can
+use a ``long`` when your values are too large to fit into an :ref:`int
+<lang-int>`.  A ``long`` occupies 8 bytes of memory.  This yields a
+range of approximately -9.2×10^18 to 9.2×10^18 (that's 9.2 billion
+billion, or about 92 million times the number of stars in the Milky
+Way galaxy).  The exact range of a ``long`` on the Maple is from
+-9,223,372,036,854,775,808 to 9,223,372,036,854,775,807, or -2^63 to
+(2^63-1).  A ``long`` it is subject to the same :ref:`overflow issues
+<lang-variables-rollover>` as any numeric data type.
+
+Here's an example of declaring a long (see :ref:`integer constants
+<lang-constants-integers-u-l>` for an explanation of the "L" at the end of the
+number)::
+
+        // Speed of light in nanometers per second (approximate).
+        long c = 299792458000000000L;
+
+The general syntax for declaring an ``long`` variable named ``var``,
+then giving it value ``val``, looks like::
+
+    long var = val;
+
+This is identical to the ``int`` syntax, with ``long`` replacing
+``int``.
+
+Note that ``long`` values will still :ref:`overflow
+<lang-int-overflow>`, just like ``int`` values, but their much
+larger range makes this less likely to happen.
+
+The downside to using a ``long`` instead of an ``int`` (besides the
+extra storage) is that :ref:`arithmetic <lang-arithmetic>` operations
+on ``long``\ s will take slightly longer than on ``int``\ s.
+
+See Also
+--------
+
+-  :ref:`char <lang-char>`
+-  :ref:`unsigned char <lang-unsignedchar>`
+-  :ref:`int <lang-int>`
+-  :ref:`unsigned int <lang-unsignedint>`
+-  :ref:`unsigned long <lang-unsignedlong>`
+-  :ref:`Integer Constants <lang-constants-integers>`
+-  :ref:`Variables <lang-variables>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/longcast.rst b/docs/source/lang/cpp/longcast.rst
new file mode 100644
index 0000000..2b92345
--- /dev/null
+++ b/docs/source/lang/cpp/longcast.rst
@@ -0,0 +1,27 @@
+.. highlight:: cpp
+
+.. _lang-longcast:
+
+``long()`` (cast)
+=================
+
+Converts a value to the :ref:`long <lang-long>` data type.  Here is
+an example::
+
+    double d = 2.5;
+    long i = long(d); // i holds "2L", an long value
+
+The value inside of the parentheses (``long(...)``) can be of any type.
+However, if it is not a numeric type (like ``double``, ``char``,
+etc.), you will get strange results.
+
+See the :ref:`long <lang-long>` reference for details about the
+precision and limitations of ``long`` variables on the Maple.
+
+See Also
+--------
+
+-  :ref:`long <lang-long>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/modulo.rst b/docs/source/lang/cpp/modulo.rst
new file mode 100644
index 0000000..289fba0
--- /dev/null
+++ b/docs/source/lang/cpp/modulo.rst
@@ -0,0 +1,70 @@
+.. highlight:: cpp
+
+.. _lang-modulo:
+
+Modulo Operator (``%``)
+=======================
+
+Calculates the `remainder <http://en.wikipedia.org/wiki/Remainder>`_
+when one integer is divided by another. It is useful for keeping a
+variable within a particular range (e.g.  the size of an array).
+
+Syntax
+------
+
+::
+
+    dividend % divisor
+
+Parameters
+----------
+
+**dividend**: the number to be divided
+
+**divisor**: the number to divide by
+
+Returns
+-------
+
+The remainder of **dividend**\ /\ **divisor**\ .
+
+Examples
+--------
+
+::
+
+    int x;
+    x = 7 % 5;   // x now contains 2
+    x = 9 % 5;   // x now contains 4
+    x = 5 % 5;   // x now contains 0
+    x = 4 % 5;   // x now contains 4
+
+::
+
+    /* update one value in an array each time through a loop */
+
+    int values[10];
+    int i = 0;
+
+    void setup() {
+        // no setup necessary
+    }
+
+    void loop() {
+      values[i] = analogRead(0);
+      i = (i + 1) % 10;   // modulo operator makes sure i stays between 0 and 9
+    }
+
+Tip
+---
+
+The modulo operator does not work on floats.  For that, you can use
+the C standard library function `fmod()
+<http://sourceware.org/newlib/libm.html#fmod>`_.
+
+See Also
+--------
+
+-  :ref:`Arithmetic <lang-arithmetic>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/pointer.rst b/docs/source/lang/cpp/pointer.rst
new file mode 100644
index 0000000..0a42270
--- /dev/null
+++ b/docs/source/lang/cpp/pointer.rst
@@ -0,0 +1,31 @@
+.. _lang-pointer:
+
+Pointer Operators (``&``, ``*``)
+================================
+
+The pointer operators ``&`` (reference) and ``*`` (dereference) are
+different from the bitwise math operator :ref:`&
+<lang-bitwisemath-and>` and the arithmetic operator :ref:`*
+<lang-arithmetic>`.
+
+Pointers are one of the more complicated subjects for beginners in
+learning C, and it is possible to write many useful Arduino sketches
+without ever encountering pointers. However, for manipulating certain
+data structures, the use of pointers can simplify the code, improve
+its efficiency, and generally provide many benefits that would be
+difficult to achieve without the use of pointers.
+
+Introducing pointers is somewhat outside the scope of this
+documentation.  However, a good `pointer tutorial
+<http://www.cplusplus.com/doc/tutorial/pointers/>`_ is available.
+Also see the `Wikipedia article on pointers
+<http://en.wikipedia.org/wiki/Pointer_%28computing%29>`_, especially
+the section on `pointers in C
+<http://en.wikipedia.org/wiki/Pointer_%28computing%29#C_pointers>`_.
+
+See Also
+--------
+
+- http://xkcd.com/138/
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/return.rst b/docs/source/lang/cpp/return.rst
new file mode 100644
index 0000000..7b5039e
--- /dev/null
+++ b/docs/source/lang/cpp/return.rst
@@ -0,0 +1,61 @@
+.. highlight:: cpp
+
+.. _lang-return:
+
+``return``
+==========
+
+Terminates a function and return a value from a function to the
+calling function, if the function has non-``void`` return type.
+
+Syntax:
+-------
+
+::
+
+    // from within a "void" function:
+    return;
+
+    // from within a non-"void" function:
+    return value;
+
+In the second case, ``value`` should have a type which is the same as
+the return type of the function, or be convertible to it (like an
+``int`` to a ``long``, etc.; see :ref:`this note
+<lang-arithmetic-typeconversion>` for some references).
+
+Examples:
+---------
+
+A function to compare a sensor input to a threshold::
+
+     // converts analog readings between 0 and 400 to 0, and 400 up to 1.
+     int checkSensor() {
+        if (analogRead(0) > 400) {
+            return 1;
+        else {
+            return 0;
+        }
+    }
+
+An early ``return`` is also useful when testing a section of code
+without having to "comment out" large sections of possibly buggy code,
+like so::
+
+    void loop() {
+
+        // brilliant code idea to test here
+
+        return;
+
+        // the rest of a dysfunctional sketch here
+        // this code will never be executed
+    }
+
+See Also
+--------
+
+- :ref:`comments <lang-comments>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/scope.rst b/docs/source/lang/cpp/scope.rst
new file mode 100644
index 0000000..7b65bab
--- /dev/null
+++ b/docs/source/lang/cpp/scope.rst
@@ -0,0 +1,120 @@
+.. highlight:: cpp
+
+.. _lang-scope:
+
+Scope
+=====
+
+Variables in the C++ programming language, which Maple uses (all of
+your sketches are C++ programs in disguise), have a property called
+*scope*.  Simply put, a variable's scope is made up of all of the
+lines where the variable can be used.
+
+Scope in C++ is a fairly complex topic, so we won't try to describe it
+in full here.  Instead, we present a simplified view, describing two
+different kinds of scopes, *global* and *local*.  For more detailed
+information, consult a C++ reference.
+
+Global and Local Variables
+--------------------------
+
+A global variable is one that can be "seen" by every function in a
+program.  In the :ref:`Maple IDE <ide>`, any variable declared outside
+of a function (like :ref:`setup() <lang-setup>` and :ref:`loop()
+<lang-loop>`) is a global variable.
+
+A local variable can only be "seen" inside of a particular function.
+You can declare a variable to be local to a function by declaring it
+inside of the :ref:`curly braces <lang-curly-braces>` which enclose
+that function.
+
+When programs start to get larger and more complex, local variables
+are a useful way to ensure that a function has exclusive access to its
+own variables.  This prevents programming errors when one function
+mistakenly modifies variables used by another function.
+
+It is also sometimes useful to declare and initialize a variable
+inside a :ref:`for <lang-for>` loop. This creates a variable that
+can only be accessed from inside the loop body.
+
+Example
+-------
+
+Here is an example sketch (which you can copy into the Maple IDE and
+run on your Maple) that illustrates the use of global and local
+variables, as well as declaring variables inside of a ``for`` loop.
+Be sure to open a :ref:`serial monitor <ide-serial-monitor>` after you
+:ref:`verify <ide-verify>` and :ref:`upload <ide-upload>` the sketch::
+
+    int globalVar;  // any function will see this variable
+
+    void setup() {
+      // since "globalVar" is declared outside of any function,
+      // every function can "see" and use it:
+      globalVar = 50;
+
+      // the variables "i" and "d" declared inside the "loop" function
+      // can't be seen here.  see what happens when you uncomment the
+      // following lines, and try to Verify (compile) the sketch:
+      //
+      // i = 16;
+      // SerialUSB.print("i = ");
+      // SerialUSB.println(i);
+      // d = 26.5;
+      // SerialUSB.print("d = ");
+      // SerialUSB.println(d);
+    }
+
+    void loop() {
+      // since "i" and "d" are declared inside of the "loop" function,
+      // they can only be seen and used from inside of it:
+      int i;
+      double d;
+
+      for (int j = 0; j < 5; j++) {
+          // variable i can be used anywhere inside the "loop" function;
+          // variable j can only be accessed inside the for-loop brackets:
+          i = j * j;
+          SerialUSB.print("i = ");
+          SerialUSB.println(i);
+      }
+
+      // globalVar can be accessed from anywhere.  note how even
+      // though we set globalVar = 50 in the "setup" function, we can
+      // see that value here:
+      SerialUSB.print("globalVar = ");
+      SerialUSB.println(globalVar);
+
+      // d can be accessed from anywhere inside the "loop" function:
+      d = 26.5;
+      SerialUSB.print("d = ");
+      SerialUSB.print(d);
+      SerialUSB.println(" (before separateFunction())");
+
+      separateFunction();
+
+      // notice how even though separateFunction() has a variable
+      // named "d", it didn't touch our (local) variable which has
+      // the same name:
+      SerialUSB.print("d = ");
+      SerialUSB.print(d);
+      SerialUSB.println(" (after separateFunction())");
+    }
+
+    void separateFunction() {
+      // variable "d" here has the same name as variable "d" inside of
+      // the "loop" function, but since they're both _local_
+      // variables, they don't affect each other:
+      double d = 30.5;
+      SerialUSB.print("d = ");
+      SerialUSB.print(d);
+      SerialUSB.println(" (inside of separateFunction())");
+    }
+
+See Also
+--------
+
+- `C++ programming Wikibook <http://en.wikibooks.org/wiki/C%2B%2B_Programming/Programming_Languages/C%2B%2B/Code/Statements/Scope>`_.
+- Wikipedia article on `scope <http://en.wikipedia.org/wiki/Scope_%28programming%29>`_
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/semicolon.rst b/docs/source/lang/cpp/semicolon.rst
new file mode 100644
index 0000000..8164616
--- /dev/null
+++ b/docs/source/lang/cpp/semicolon.rst
@@ -0,0 +1,25 @@
+.. highlight:: cpp
+
+.. _lang-semicolon:
+
+Semicolon (``;``)
+=================
+
+Used to end a line of code.  Example::
+
+    int a = 13;
+
+Tip
+---
+
+Forgetting to end a line in a semicolon will result in a compiler
+error. The error text may be obvious, and refer to a missing
+semicolon, or it may not. If an impenetrable or seemingly illogical
+compiler error comes up, one of the first things to check is a
+missing semicolon, in the immediate vicinity, preceding the line at
+which the compiler complained.
+
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/sizeof.rst b/docs/source/lang/cpp/sizeof.rst
new file mode 100644
index 0000000..eae509c
--- /dev/null
+++ b/docs/source/lang/cpp/sizeof.rst
@@ -0,0 +1,64 @@
+.. highlight:: cpp
+
+.. _lang-sizeof:
+
+``sizeof()``
+============
+
+The ``sizeof`` operator on the Maple returns the number of bytes
+needed to store a value of a given type\ [#fcharsize]_.  This can be
+an ordinary numeric type, like ``int``.  It can be something more
+complicated, like a ``struct`` or ``union``.  If the argument to
+``sizeof`` is an array, it returns the total number of bytes occupied
+by the array.
+
+The general syntax looks like this::
+
+    sizeof(type)
+    sizeof(var)
+
+Example
+-------
+
+The ``sizeof`` operator is useful for dealing with arrays (such as
+strings) where it is convenient to be able to change the size of the
+array without breaking other parts of the program.
+
+This program prints out a text string one character at a time. Try
+changing the text phrase::
+
+    char myStr[] = "this is a test";
+    int i;
+
+    void setup() {
+      Serial.begin(9600);
+    }
+
+    void loop() {
+      for (i = 0; i < sizeof(myStr) - 1; i++) {
+        Serial.print(i, DEC);
+        Serial.print(" = ");
+        Serial.println(myStr[i], BYTE);
+      }
+    }
+
+
+Note that ``sizeof`` returns the total number of bytes. So for larger
+variable types such as ``int``, the :ref:`for loop <lang-for>`
+would look something like this::
+
+    for (i = 0; i < (sizeof(myInts)/sizeof(int)) - 1; i++) {
+      // do something with myInts[i]
+    }
+
+.. rubric:: Footnotes
+
+.. [#fcharsize] Technically (and pedantically) speaking, ``sizeof``
+   returns a multiple of the number of bits a ``char`` occupies in
+   memory.  However, on the Maple (this goes for most C++
+   implementations), a ``char`` occupies 8 bits = 1 byte.  All the C++
+   standard guarantees, however, is that a ``char`` occupies at
+   *least* 8 bits.
+
+.. include:: cc-attribution.txt
+
diff --git a/docs/source/lang/cpp/sqrt.rst b/docs/source/lang/cpp/sqrt.rst
new file mode 100644
index 0000000..956a754
--- /dev/null
+++ b/docs/source/lang/cpp/sqrt.rst
@@ -0,0 +1,25 @@
+.. _lang-sqrt:
+
+sqrt()
+======
+
+Calculates the square root of a number.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: sqrt
+
+Arduino Compatibility
+---------------------
+
+The Maple versino of ``sqrt()`` is compatible with Arduino.
+
+See Also
+--------
+
+-  :ref:`pow <lang-pow>`
+-  :ref:`sq <lang-sq>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/static.rst b/docs/source/lang/cpp/static.rst
new file mode 100644
index 0000000..5d1802e
--- /dev/null
+++ b/docs/source/lang/cpp/static.rst
@@ -0,0 +1,57 @@
+.. highlight:: cpp
+
+.. _lang-static:
+
+``static``
+==========
+
+The ``static`` keyword can be used to create variables that are
+visible to only one function. However, unlike local variables that get
+created and destroyed every time a function is called, ``static``
+variables persist beyond the function call, preserving their data
+between function calls.
+
+Variables declared as ``static`` will only be created and initialized
+the first time a function is called.
+
+.. note:: This is only one use of the ``static`` keyword in C++.  It
+   has some other important uses that are not documented here; consult
+   a reliable C++ reference for details.
+
+Example
+-------
+
+One use case for ``static`` variables is implementing counters that
+last longer than the functions which need them, but shouldn't be
+shared to other functions.  Here's an example::
+
+    void setup() {
+        SerialUSB.begin();
+    }
+
+    void loop() {
+        int reading;
+        if (timeToReadSensors()) {
+            reading = readSensors();
+        }
+        // do something with reading
+    }
+
+    int readSensors() {
+        static int numSensorReadings = 0;
+        numSensorReadings++;
+        if (numSensorReadings % 100 == 0) {
+            SerialUSB.print("just got to another 100 sensor readings");
+        }
+        return analogRead(...);
+    }
+
+In this example, the static variable ``numSensorReadings`` is
+initialized to zero the first time ``readSensors()`` is called, and
+then incremented, so it starts out at one.  Subsequent calls to
+``readSensors()`` won't reset ``numSensorReadings`` to zero, because
+it was declared ``static``.  Thus, ``numSensorReadings`` is a count of
+the number of times that ``readSensors()`` has been called.
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/string.rst b/docs/source/lang/cpp/string.rst
new file mode 100644
index 0000000..0a270da
--- /dev/null
+++ b/docs/source/lang/cpp/string.rst
@@ -0,0 +1,128 @@
+.. highlight:: cpp
+
+.. _lang-string:
+
+Strings
+=======
+
+Text strings can be represented in two ways.  You can
+
+1. Use the :ref:`String <lang-stringclass>` data type, which is
+part of the core as of version 0.0.9, or
+
+2. You can make a string out of an array of type :ref:`char
+<lang-char>` and null-terminate it.
+
+This page describes the second method.
+
+Examples
+--------
+
+All of the following are valid declarations for strings::
+
+      char str1[15];
+      char str2[6] = {'m', 'a', 'p', 'l', 'e'};
+      char str3[6] = {'m', 'a', 'p', 'l', 'e', '\0'};
+      char str4[ ] = "maple";
+      char str5[6] = "maple";
+      char str6[15] = "maple";
+
+As you can see, there are several methods available for declaring and
+initializing strings:
+
+- Declare an array of ``char`` without initializing it, as with ``str1``.
+
+- Declare an array of ``char`` (with one extra ``char``) and the
+  compiler will add the required null character, as with ``str2``.
+
+- Explicitly add the null character (``'\0'``), as with ``str3``.
+
+- Initialize with a string constant in quotation marks (``"..."``);
+  the compiler will size the array to fit the string constant and a
+  terminating null character (``str4``).
+
+- Initialize the array with an explicit size and string constant,
+  (``str5``).
+
+- Initialize the array, leaving extra space for a larger string
+  (``str6``).
+
+Null Termination
+----------------
+
+Generally, strings are terminated with a null character (`ASCII
+<http://en.wikipedia.org/wiki/ASCII>`_ code 0). This allows functions
+(like ``SerialUSB.print()``) to tell where the end of a string is.
+Otherwise, they would continue reading subsequent bytes of memory that
+aren't actually part of the string.
+
+This means that your string needs to have space for one more character
+than the text you want it to contain. That is why ``str2`` and
+``str5`` need to be six characters, even though "maple" is only five
+-- the last position is automatically filled with a NULL
+character. ``str4`` will be automatically sized to six characters, one
+for the extra null. In the case of ``str3``, we've explicitly included
+the null character (written ``'\0'``) ourselves.
+
+Note that it's possible to have a string without a final null
+character (e.g. if you had specified the length of ``str2`` as five
+instead of six). This will break most functions that use strings, so
+you shouldn't do it intentionally. If you notice something behaving
+strangely (operating on characters not in the string), however, this
+could be the problem.
+
+Single quotes or double quotes?
+-------------------------------
+
+Strings are always defined inside double quotes (``"Abc"``) and
+characters are always defined inside single quotes (``'A'``).
+
+Wrapping long strings
+---------------------
+
+You can wrap long strings like this::
+
+    char myString[] = "This is the first line"
+                      " this is the second line"
+                      " etcetera";
+
+Arrays of Strings
+-----------------
+
+It is often convenient, when working with large amounts of text,
+such as a project with an LCD display, to setup an array of
+strings. Because strings themselves are arrays, this is in actually
+an example of a two-dimensional array.
+
+In the code below, the asterisk after the datatype char ``char *``
+indicates that this is an array of "pointers". All array names are
+actually pointers, so this is required to make an array of arrays.
+Pointers are one of the more esoteric parts of C for beginners to
+understand, but it isn't necessary to understand pointers in detail to
+use them effectively here::
+
+    char* myStrings[] = {"This is string 1", "This is string 2",
+                         "This is string 3", "This is string 4",
+                         "This is string 5", "This is string 6"};
+
+    void setup() {
+        SerialUSB.begin();
+    }
+
+    void loop() {
+        for (int i = 0; i < 6; i++) {
+            SerialUSB.println(myStrings[i]);
+            delay(500);
+        }
+    }
+
+
+See Also
+--------
+
+- :ref:`array <lang-array>`
+- :ref:`__attribute__ <arm-gcc-attribute-flash>`
+- :ref:`Variables <lang-variables>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/switchcase.rst b/docs/source/lang/cpp/switchcase.rst
new file mode 100644
index 0000000..b484bc5
--- /dev/null
+++ b/docs/source/lang/cpp/switchcase.rst
@@ -0,0 +1,118 @@
+.. highlight:: cpp
+
+.. _lang-switchcase:
+
+``switch``\ /\ ``case``
+=======================
+
+Like :ref:`if <lang-if>` statements, A ``switch`` statement controls
+program flow by allowing you to specify different code that should be
+executed under various cases.
+
+The general syntax looks like this::
+
+    switch (var) {
+    case val1:
+        // statements
+        break;
+    case val2:
+        // statements
+        break;
+    ...
+    default:
+        // statements
+    }
+
+Where ``var`` is a variable whose value to investigate, and the
+``val1``, ``val2`` after each ``case`` are constant values that
+``var`` might be.
+
+Description
+-----------
+
+A ``switch`` statement compares the value of a variable to the values
+specified in ``case`` statements. When a ``case`` statement is found
+whose value matches that of the variable, the code in that case
+statement is run.
+
+Here's a more concrete example::
+
+      switch (var) {
+      case 1:
+          doThing1();
+          break;
+      case 2:
+          doThing2();
+          break;
+      }
+      afterTheSwitch();
+
+In the above example, if ``var == 1``, then the code beginning on the
+line after ``case 1`` gets executed.  That is, if ``var`` is one,
+``doThing1()`` gets called first, and then the ``break`` statement is
+executed.
+
+The ``break`` keyword exits the ``switch`` statement, and is typically
+used at the end of each ``case``.  Since there is a ``break`` at the
+end of ``case 1``, the ``switch`` statement exits, and the next line
+to be run is the one which calls ``afterTheSwitch()``.
+
+Without a ``break``, the ``switch`` statement will continue executing
+the following ``case`` expressions ("falling-through") until a
+``break`` (or the end of the switch statement) is reached.  Let's
+pretend the ``switch`` looked like this instead::
+
+      switch (var) {
+      case 1:
+          doThing1();
+          // no break statement anymore
+      case 2:
+          doThing2();
+          break;
+      }
+      afterTheSwitch();
+
+Now, if ``var`` is one, ``doThing1()`` gets executed like before.
+However, without a ``break``, the code would continue to be executed
+line-by-line, so ``doThing2()`` would be called next.  At this point,
+a ``break`` has been reached, so the program continues by calling
+``afterTheSwitch()``.  This is usually not what you want, which is why
+each ``case`` usually has a ``break`` at the end.
+
+.. _lang-switchcase-default:
+
+Writing "``default:``" instead of a ``case`` statement allows you to
+specify what to do if none of the ``case`` statements matches.  Having
+a ``default`` is optional (you can leave it out), but if you have one,
+it must appear after all of the ``case`` statements.  Let's add a
+``default`` to the ``switch`` we've been discussing::
+
+      switch (var) {
+      case 1:
+          doThing1();
+          break;
+      case 2:
+          doThing2();
+          break;
+      default:
+          doSomethingElse();
+      }
+      afterTheSwitch();
+
+If ``var`` is one, then ``doThing1()`` gets called.  If ``var`` is
+two, ``doThing2()`` gets called.  If ``var`` is anything else,
+``doSomethingElse()`` gets called.  As stated above, a ``default`` is
+optional.  If you're missing one and none of the ``case`` statements
+match, the ``switch`` does nothing at all, as if it weren't there.
+
+``switch`` statements are often used with an :ref:`enum <lang-enum>`
+value as the variable to compare.  In this case, you can write down
+all of the values the ``enum`` takes as ``case`` statements, and be
+sure you've covered all the possibilities.
+
+See also:
+---------
+
+- :ref:`if/else <lang-if>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/unsignedchar.rst b/docs/source/lang/cpp/unsignedchar.rst
new file mode 100644
index 0000000..5b946ed
--- /dev/null
+++ b/docs/source/lang/cpp/unsignedchar.rst
@@ -0,0 +1,33 @@
+.. highlight:: cpp
+
+.. _lang-unsignedchar:
+
+``unsigned char``
+=================
+
+An unsigned version of the :ref:`char <lang-char>` data type.  An
+``unsigned char`` occupies 1 byte of memory; it stores an integer from
+0 to 255.
+
+Like an :ref:`unsigned int <lang-unsignedint>`, an ``unsigned char``
+won't store negative numbers; it is also subject to the same
+:ref:`overflow issues <lang-int-overflow>` as any integral data type.
+
+Example
+-------
+
+::
+
+        unsigned char c = 240;
+
+See Also
+--------
+
+
+- :ref:`byte <lang-byte>`
+- :ref:`int <lang-int>`
+- :ref:`array <lang-array>`
+- :ref:`SerialUSB.println() <lang-serialusb-println>`
+- :ref:`Serial.println() <lang-serial-println>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/unsignedint.rst b/docs/source/lang/cpp/unsignedint.rst
new file mode 100644
index 0000000..f6311da
--- /dev/null
+++ b/docs/source/lang/cpp/unsignedint.rst
@@ -0,0 +1,55 @@
+.. 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
diff --git a/docs/source/lang/cpp/unsignedlong.rst b/docs/source/lang/cpp/unsignedlong.rst
new file mode 100644
index 0000000..14a4fc3
--- /dev/null
+++ b/docs/source/lang/cpp/unsignedlong.rst
@@ -0,0 +1,41 @@
+.. highlight:: cpp
+
+.. _lang-unsignedlong:
+
+``unsigned long``
+=================
+
+An unsigned version of the :ref:`long <lang-long>` data type.  An
+``unsigned long`` occupies 8 bytes of memory; it stores an integer
+from 0 to 2^64-1, which is approximately 1.8×10^19 (18 quintillion, or
+18 billion billion).
+
+Like an :ref:`unsigned int <lang-unsignedint>`, an ``unsigned long``
+won't store negative numbers; it is also subject to the same
+:ref:`overflow issues <lang-int-overflow>` as any integral data type.
+
+Here is an example of declaring an ``unsigned long`` variable named
+``c``, then giving it value 299,792,458,000,000,000 (see :ref:`integer
+constants <lang-constants-integers-u-l>` for an explanation of the "L"
+at the end of the number)::
+
+        // Speed of light in nanometers per second (approximate).
+        unsigned long c = 299792458000000000L;
+
+The general syntax for declaring an ``unsigned long`` variable named
+``var``, then giving it value ``val``, looks like::
+
+        unsigned long var = val;
+
+See Also
+--------
+
+-  :ref:`long <lang-long>`
+-  :ref:`int <lang-int>`
+-  :ref:`unsigned <lang-unsignedint>`
+-  :ref:`char <lang-char>`
+-  :ref:`unsigned char <lang-unsignedchar>`
+-  :ref:`Integer Constants <lang-constants-integers>`
+-  :ref:`Variables <lang-variables>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/variables.rst b/docs/source/lang/cpp/variables.rst
new file mode 100644
index 0000000..e6da0c9
--- /dev/null
+++ b/docs/source/lang/cpp/variables.rst
@@ -0,0 +1,170 @@
+.. highlight:: cpp
+
+.. _lang-variables:
+
+Variables
+=========
+
+A variable is a way of naming and storing a value for later use by
+the program, such as data from a sensor or an intermediate value
+used in a calculation.
+
+.. contents:: Contents
+   :local:
+
+.. _lang-variables-declaring:
+
+Declaring Variables
+-------------------
+
+Before they are used, all variables have to be *declared*. Declaring a
+variable means defining its type, giving it a name, and (optionally)
+giving it an initial value (this is often referred to as
+*initializing* the variable).  Variables do not have to be initialized
+(given a value) when they are declared, but it is good style to give
+them an initial value whenever possible.
+
+Here is an example of declaring a variable named ``inputVariable1``
+with type :ref:`int <lang-int>` (the ``int`` type is used to store
+integers, like -2, -1, 0, 1, etc.)::
+
+    int inputVariable1;
+
+In the above declaration, we did not give the variable an initial
+value.  Here is another example, where we declare an ``int`` variable
+named ``inputVariable2``, with an initial value of ``0``::
+
+    int inputVariable2 = 0;
+
+The Maple environment comes ready to use with many useful types of
+variables.  See the :ref:`built-in types <lang-built-in-types>` page
+for more information.
+
+Here are a few examples of declaring variables of different types::
+
+     int lightSensVal;
+     char currentLetter;
+     unsigned long speedOfLight = 186000UL;
+     char errorMessage = {"choose another option"}; // see string
+
+Naming Variables
+----------------
+
+The rules for naming a variable are simple.  Names for variables can
+contain letters, numbers, and underscores (the underscore is the
+:kbd:`_` character), and cannot begin with a number.  So
+``temperature_reading``, ``tempReading``, ``tempReading1``, and
+``tempReading2`` are all valid variable names, but ``4_temp_readings``
+is not, because it begins with a number.
+
+You cannot choose a name for a variable that is one of the C++
+:ref:`keywords <lang-keywords>`.
+
+Variable names are case-sensitive, so "tempreading" and "tempReading"
+are different variables.  However, it is very bad style to write code
+that chooses variables which are the same up to case.
+
+You should give your variables descriptive names, so as to make your
+code more readable. Variable names like ``tiltSensor`` or
+``pushButton`` help you (and anyone else reading your code) understand
+what the variable represents. Variable names like ``var`` or
+``value``, on the other hand, do little to make your code readable.
+
+.. _lang-variables-scope:
+
+Variable Scope
+--------------
+
+An important choice that programmers face is where (in the program
+text) to declare variables. The specific place that variables are
+declared influences how various functions in a program will "see" the
+variable.  This is called variable *scope*.  See the :ref:`scope
+reference <lang-scope>` for more information.
+
+.. _lang-variables-initializing:
+
+Initializing Variables
+----------------------
+
+Variables may be *initialized* (assigned a starting value) when they
+are declared or not. It is always good programming practice however to
+double check that a variable has valid data in it before it is used.
+Using a variable before you give it a value is a common source of
+bugs.
+
+.. _lang-variables-rollover:
+
+Variable Rollover
+-----------------
+
+Every (numeric) type has a valid *range*.  The range of a type is the
+smallest and largest value that a variable of that type can store.
+For example, the :ref:`int <lang-int>` type has a range of
+-2,147,483,648 to 2,147,483,647 [#frange]_.
+
+When variables are made to exceed their range's maximum value, they
+"roll over" back to their minimum value.  Note that this happens in
+both directions.  It's like in the game *Pac-Man* -- when Pac-Man goes
+past the right edge of the screen, he reappears on the left, and when
+he goes past the left side of the screen, he reappears on the right::
+
+       int x;
+       x = -2,147,483,648;
+       x = x - 1; // x now contains -2,147,483,647; rolled over "left to right"
+
+       x = 2,147,483,647;
+       x = x + 1; // x now contains -2,147,483,648; rolled over "right to left"
+
+Each numeric type's reference page includes its range.  See the
+:ref:`built-in types <lang-built-in-types>` reference for links to each
+type's reference page.
+
+Using Variables
+---------------
+
+Once variables have been declared, they are given values using the
+:ref:`assignment operator <lang-assignment>`, which is a single equals
+sign, ``=``. The assignment operator tells the program to store the
+value on the right side of the equals sign into the variable on the
+left side::
+
+    inputVariable1 = 7;             // sets variable named inputVariable1 to 7
+    inputVariable2 = analogRead(2); // sets variable named inputVariable2 to
+                                    // the (digitized) input voltage read from
+                                    //  analog pin #2
+
+Once a variable has been set (assigned a value), you can test its
+value to see if it meets certain conditions, or you can use its value
+directly. For instance, the following code tests whether the
+inputVariable2 is less than 100, then sets a delay based on
+inputVariable2 (which, at that point, is at least 100)::
+
+    if (inputVariable2 < 100) {
+      inputVariable2 = 100;
+    }
+
+    delay(inputVariable2);
+
+See Also
+--------
+
+- :ref:`lang-scope`
+- :ref:`lang-built-in-types`
+
+.. rubric:: Footnotes
+
+.. [#frange] This range might seem a little weird at first.  The
+   reasons for this range of values have to do with the fact that an
+   ``int`` occupies 32 bits of memory, and the facts ::
+
+     2^31 = -2,147,483,648
+     2^31 - 1 = 2,147,483,647
+
+
+   Why 2^31 instead of 2^32?  Well, that has to do with `how ints are
+   (usually) stored
+   <http://en.wikipedia.org/wiki/Two%27s_complement>`_ on computers.
+
+
+.. include:: cc-attribution.txt
+
diff --git a/docs/source/lang/cpp/void.rst b/docs/source/lang/cpp/void.rst
new file mode 100644
index 0000000..88c9c64
--- /dev/null
+++ b/docs/source/lang/cpp/void.rst
@@ -0,0 +1,33 @@
+.. highlight:: cpp
+
+.. _lang-void:
+
+``void``
+========
+
+.. cpp:type:: void
+
+   The ``void`` keyword is used in function declarations. It indicates
+   that the function is expected to return no information to the
+   function from which it was called, or that it expects no arguments
+   from its caller.
+
+Example
+-------
+
+::
+
+    // actions are performed in the functions "setup" and "loop"
+    // but  no information is reported to the larger program
+
+    void setup() {
+      // ...
+    }
+
+    void loop() {
+      // ...
+    }
+
+.. TODO doc page on function declaration?
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/cpp/while.rst b/docs/source/lang/cpp/while.rst
new file mode 100644
index 0000000..9047d05
--- /dev/null
+++ b/docs/source/lang/cpp/while.rst
@@ -0,0 +1,38 @@
+.. highlight:: cpp
+
+.. _lang-while:
+
+``while``
+=========
+
+Syntax
+------
+
+::
+
+    while (expression) {
+      // block of code
+    }
+
+Description
+-----------
+
+``while`` loops will repeat the statements inside their associated
+block of code until the expression inside the parentheses becomes
+:ref:`false <lang-constants-false>`. Something must change the tested
+expressions' value, or the ``while`` loop will never exit.  This could
+be in your code, such as an incremented variable, or an external
+condition, such as testing a sensor.
+
+Example
+-------
+
+::
+
+    var = 0;
+    while(var < 200) {
+      // do something repetitive 200 times
+      var++;
+    }
+
+.. include:: cc-attribution.txt