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diff --git a/docs/source/lang/api/abs.rst b/docs/source/lang/api/abs.rst
new file mode 100644
index 0000000..0cc6c23
--- /dev/null
+++ b/docs/source/lang/api/abs.rst
@@ -0,0 +1,49 @@
+.. highlight:: cpp
+
+.. _lang-abs:
+
+
+abs()
+======
+
+(Macro) computes the absolute value of a number.
+
+Syntax
+------
+
+::
+
+   abs(x)
+
+Parameters
+----------
+
+**x**: the number.
+
+Returns
+-------
+
+**x**: if **x** is greater than or equal to 0.
+
+**-x**: if **x** is less than 0.
+
+Warning
+-------
+
+Because of the way ``abs()`` is implemented, avoid using other
+functions or causing side effects inside the parentheses, as it may
+lead to incorrect results::
+
+    abs(a++);   // avoid this - yields incorrect results
+
+    abs(a);       // use this instead -
+    a++;          // keep other operations outside abs()
+
+
+Arduino Compatibility
+---------------------
+
+Maple's implementation of ``abs()`` is compatible with Arduino.
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/analogread.rst b/docs/source/lang/api/analogread.rst
new file mode 100644
index 0000000..35c6fbc
--- /dev/null
+++ b/docs/source/lang/api/analogread.rst
@@ -0,0 +1,119 @@
+.. highlight:: cpp
+
+.. _lang-analogread:
+
+.. _lang-api-analogread:
+
+analogRead()
+============
+
+Used to perform ADC conversion.
+
+.. contents:: Contents
+   :local:
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: analogRead
+
+Discussion
+----------
+
+Reads the value from the specified analog pin.  The Maple board
+contains a 16-channel, 12-bit analog to digital converter.  This means
+that it will map input voltages between 0 and 3.3 volts into integer
+values between 0 and 4095.  This yields a resolution between readings
+of 3.3V / 4096 units, or 0.8 millivolts.  However, a number of factors
+interfere with getting full accuracy and precision.  For more
+information, see :ref:`adc`.
+
+Before calling analogRead() on a pin, that pin must first be
+configured for analog input, using :ref:`lang-pinMode` (you only
+have to do this once, so it's usually done in :ref:`lang-setup`\ ).
+
+Parameter Discussion
+--------------------
+
+The pin parameter is the number of the analog input pin to read from.
+Header pins on the Maple with ADC functionality (marked as "AIN" on
+the silkscreen) are:
+
+  0, 1, 2, 3, 10, 11, 12, 13, 15, 16, 17, 18, 19, 20, 27, 28
+
+Note that pins 3, 27, and 28 are not marked AIN on the silkscreen
+for Maple revisions through Rev 5, however, they **do work** as
+analog input pins.
+
+Note
+----
+
+If the analog input pin is not connected to anything, the value
+returned by analogRead() will fluctuate based on a number of factors
+(e.g. the values of the other analog inputs, how close your hand is to
+the board, etc.) in a seemingly random way.
+
+
+Example
+-------
+
+ ::
+
+
+    int analogPin = 3;     // potentiometer wiper (middle terminal) connected
+                           // to analog pin 3. outside leads to ground and +3.3V
+    int val = 0;           // variable to store the value read
+
+    void setup() {
+      pinMode(analogPin, INPUT_ANALOG); // set up pin for analog input
+      SerialUSB.begin();                // set up usb virtual COM port
+    }
+
+    void loop() {
+      val = analogRead(analogPin);    // read the input pin
+      SerialUSB.println(val);         // print the value, for debugging with
+                                      // a serial monitor
+    }
+
+
+Arduino Compatibility
+---------------------
+
+The Arduino board contains a 6 channel (8 channels on the Mini and
+Nano, 16 on the Mega), 10-bit analog to digital converter with an
+input voltage range of 0V--5V. This means that it will map input
+voltages between 0 and 5 volts (which is **larger** than Maple's range
+of 0V-3.3V) into integer values between 0 and 1023 (which is
+**smaller** than the Maple's range of 0--4095).
+
+This yields a theoretical resolution between readings of: 5 volts /
+1024 units or .0049 volts (4.9 mV) per unit on Arduino boards, which
+is larger, and thus less precise, than Maple's 0.0008 volts (0.8 mV).
+
+If your program expects Arduino-style 10-bit ADC, you can :ref:`right
+shift <lang-bitshift>` the value of a Maple readout by 2, like so::
+
+    // right shift means that the result will be between 0 and 1023;
+    // be aware that you're losing a lot of precision if you do this
+    int adc_reading = analogRead(pin) >> 2;
+
+On the Arduino, the input range and resolution can be changed using
+their implementation of `analogReference()
+<http://arduino.cc/en/Reference/AnalogReference>`_\ . Because of the
+way its hardware (as of Rev 5) was designed, it's not possible to
+implement analogReference on the Maple, so this function doesn't
+exist.  If your inputs lie in a different voltage range than 0V--3.3V,
+you'll need to bring them into that range before using analogRead.
+Some basic tools to accomplish this are `resistor dividers
+<http://en.wikipedia.org/wiki/Voltage_divider>`_ and `Zener diodes
+<http://en.wikipedia.org/wiki/Voltage_source#Zener_voltage_source>`_\
+. However, opamps and other powered components can also be used if
+greater precision is required.
+
+See also
+--------
+
+- :ref:`ADC note <adc>`
+- `(Arduino) Tutorial: Analog Input Pins <http://arduino.cc/en/Tutorial/AnalogInputPins>`_
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/analogwrite.rst b/docs/source/lang/api/analogwrite.rst
new file mode 100644
index 0000000..9147b96
--- /dev/null
+++ b/docs/source/lang/api/analogwrite.rst
@@ -0,0 +1,173 @@
+.. highlight:: cpp
+
+.. _lang-analogwrite:
+
+.. _lang-api-analogwrite:
+
+
+analogWrite()
+=============
+
+.. note::
+
+   On the Maple, calling analogWrite() is the same as calling
+   :ref:`lang-pwmwrite`\ ; we recommend using that function directly
+   instead.
+
+   This is because PWM is not true analog output (i.e., is not the
+   output of a `DAC
+   <http://en.wikipedia.org/wiki/Digital-to-analog_converter>`_\ ), so
+   the function is badly named.  For instance, analogWrite() **has
+   absolutely nothing to do with** :ref:`lang-analogread`\ , which is
+   potentially confusing.
+
+   The alias of analogWrite() to pwmWrite() is provided for the sake
+   of compatibility with Arduino only.
+
+.. contents:: Contents
+   :local:
+
+.. _lang-analogwrite-compatibility:
+
+Arduino Compatibility
+---------------------
+
+There are a few important differences between Arduino's `analogWrite()
+<http://arduino.cc/en/Reference/AnalogWrite>`_ and Maple's
+:ref:`lang-pwmwrite` that you should keep in mind.  In each case, we
+have some recommendations you can use to help converting from Arduino
+to Maple.
+
+Difference 1: Duty cycle range is different
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The first and most important difference is that the largest possible
+value for the duty cycle is much bigger on the Maple.  Using Arduino's
+analogWrite(), the duty cycle ranges between 0--255 (always off --
+always on)\ [#fbytemax]_\ .  Using Maple's pwmWrite(), the duty cycle
+ranges from 0--65,535 by default\ [#fuint16max]_\ .
+
+This is a good thing!  The greater range of values on the Maple gives
+you much more precise control over the duty cycle of your PWM output.
+
+If you're porting code from the Arduino and want a quick-and-dirty
+fix, one solution is to :ref:`map <lang-map>` the argument to
+analogWrite into the right range::
+
+    // Arduino code:
+    analogWrite(pin, duty);
+
+    // Becomes Maple code:
+    analogWrite(pin, map(duty, 0, 255, 0, 65535));
+
+This will convert values in the range 0-255 to values in the range
+0--65,635, which is the correct default range for all of the timers
+which control PWM output.  See the :ref:`timers reference <timers>`
+for more information.
+
+Another fix is to consult the :ref:`pin mapping mega table
+<pin-mapping-mega-table>` to find the timer which controls PWM on the
+pin you're using, then set that Timer's overflow to 255.  Subsequent
+calls to analogWrite() should work as on the Arduino (with the same
+loss of precision).  Note, however, that that affects the overflow for
+the **entire timer**, so other code relying on that timer (such as any
+:ref:`interrupts <lang-attachinterrupt>` the timer controls) will
+likely need to be modified as well.
+
+Difference 2: You must use pinMode() to set up PWM
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The second difference is that on the Maple, you **must** set up the pin
+for PWM output using :ref:`lang-pinmode`\ , with argument ``PWM``.
+This should just be one extra line of code in your
+:ref:`lang-setup` function.  Example::
+
+    void setup() {
+        // set up pin 9 for PWM
+        pinMode(9, PWM);
+    }
+
+This also means that you can't later call :ref:`lang-digitalread`
+or :ref:`lang-digitalwrite` on that pin (unless some time in
+between, you use pinMode() to reconfigure that pin for ``INPUT`` or
+``OUTPUT``; see the :ref:`lang-pinmode` page for more information).
+
+Difference 3: No PWM on pin 10
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+On the Maple, the pins which support PWM are: 0, 1, 2, 3, 5, 6, 7, 8,
+9, 11, 12, 14, 24, 27, and 28 or fifteen pins in total.  That's *more*
+PWM-capable pins as any Arduino board, but there are differences in
+*which* pins support PWM.
+
+* On **most Arduino boards** (those with the ATmega168 or ATmega328;
+  this includes the **Arduino Uno**), this function works on pins 3,
+  5, 6, 9, 10, and 11, or six pins total.  Note that these boards
+  support PWM on pin 10, while Maple does not.
+
+* On the **Arduino Mega**, PWM works on pins 2 through 13, or twelve
+  pins total.  Note that this board supports PWM on pins 4, 10, and
+  13, while the Maple does not.
+
+* **Older Arduino boards** with an ATmega8 only support analogWrite()
+  on pins 9, 10, and 11.  Maple does not support PWM on pin 10.
+
+In all cases, Arduino boards support PWM on pin 10, unlike Maple.  We
+did our best to make PWM as pin-compatible as possible; however,
+circuit layout constraints prevented us from achieving perfect
+compatibility.
+
+The "safest" pins to use for PWM output are pins 9 and 11.  These pins
+work on any Arduino board and on Maple.  The "safe" pins, which work
+on most recent Arduino boards, the Arduino Mega and the Maple, are
+pins 3, 5, 6, 9, and 11.  Thus, if you want your project to be as
+portable as possible between Maple and Arduino, we recommend using the
+"safest" pins first, then the "safe" pins, then any other pins, as
+necessary.
+
+Difference 4: PWM frequency
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The frequency of the PWM signal (i.e., the frequency of a complete
+on/off cycle) on the Arduino is approximately 490 Hz.
+
+On the Maple, the frequency is configurable, defaulting to about 1100
+Hz, or 1.1 KHz.  This is because the PWM frequency is the frequency of
+the timer which controls PWM output on the particular pin (\
+:ref:`the PWM tutorial has the details <pwm>`\ ).
+
+If your application definitely requires Arduino's PWM frequency, then
+the steps are:
+
+1. Figure out which :ref:`timer <lang-hardwaretimer>` controls PWM
+   output on your pin (\ :ref:`this table <pwm-timer-table>` is your
+   friend here).  Let's say it's ``Timern``\ , where ``n`` is some
+   number 1, 2, 3, or 4.
+
+2. Call ``Timern.setPeriod(2041)``\ .  This will set the timer's
+   period to approximately 2041 microseconds, which is a frequency of
+   approximately 490 Hz.
+
+Be aware that this will change the period for the **entire timer**\ ,
+and will affect anything else in your program that depends on that
+timer.  The important examples are :ref:`timer interrupts
+<lang-hardwaretimer-attachinterrupt>` and :ref:`PWM
+<timers-pwm-conflicts>`\ .
+
+See also
+--------
+
+-  :ref:`Maple PWM tutorial <pwm>`
+
+.. rubric:: Footnotes
+
+.. [#fbytemax] This is because the value for the duty cycle on Arduino
+   must fit in 1 byte of memory, and an unsigned (i.e., nonnegative)
+   integer with size 1 byte can hold the values between 0 and 255.
+
+.. [#fuint16max] This is because the value for the duty cycle on the
+   Maple uses 2 bytes of memory, and an unsigned (i.e., nonnegative)
+   integer with size 2 bytes can hold the values between 0 and 65,535.
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/attachinterrupt.rst b/docs/source/lang/api/attachinterrupt.rst
new file mode 100644
index 0000000..0b8907f
--- /dev/null
+++ b/docs/source/lang/api/attachinterrupt.rst
@@ -0,0 +1,102 @@
+.. highlight:: cpp
+
+.. _lang-attachinterrupt:
+
+attachInterrupt()
+=================
+
+Used to specify a function to call when an external interrupt (like an
+GPIO changing from LOW to HIGH, a button getting pressed, etc.)
+occurs.
+
+.. contents:: Contents
+   :local:
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: attachInterrupt
+
+.. doxygenenum:: ExtIntTriggerMode
+
+.. doxygentypedef:: voidFuncPtr
+
+Discussion
+----------
+
+Because the function will run in interrupt context, inside of it,
+:ref:`lang-delay` won't work, and the value returned by
+:ref:`lang-millis` will not increment. Serial data received while
+in the function may be lost. You should declare as ``volatile`` any
+global variables that you modify within the attached function.
+
+There are a few constraints you should be aware of if you're using
+more than one interrupt at a time; the :ref:`external-interrupts` page
+has the details.
+
+
+Using Interrupts
+----------------
+
+Interrupts are useful for making things happen automatically in
+microcontroller programs, and can help solve timing problems. A
+good task for using an interrupt might be reading a rotary encoder,
+or monitoring user input.
+
+
+If you wanted to insure that a program always caught the pulses
+from a rotary encoder, never missing a pulse, it would make it very
+tricky to write a program to do anything else, because the program
+would need to constantly poll the sensor lines for the encoder, in
+order to catch pulses when they occurred. Other sensors have a
+similar interface dynamic too, such as trying to read a sound
+sensor that is trying to catch a click, or an infrared slot sensor
+(photo-interrupter) trying to catch a coin drop. In all of these
+situations, using an interrupt can free the microcontroller to get
+some other work done while not missing the doorbell.
+
+
+Example
+-------
+
+::
+
+    int maple_led_pin = 13;
+    volatile int state = LOW; // must declare volatile, since it's
+                              // modified within the blink handler
+
+    void setup() {
+      pinMode(maple_led_pin, OUTPUT);
+      attachInterrupt(0, blink, CHANGE);
+    }
+
+    void loop() {
+      digitalWrite(maple_led_pin, state);
+    }
+
+    void blink() {
+      state = !state;
+    }
+
+
+Arduino Compatibility
+---------------------
+
+Most Arduino boards have two external interrupts: numbers 0 (on
+digital pin 2) and 1 (on digital pin 3). The Arduino Mega has an
+additional four: numbers 2 (pin 21), 3 (pin 20), 4 (pin 19), and 5
+(pin 18).  On the Maple, you don't have to remember which interrupt
+number goes with which pin -- just tell ``attachInterrupt()`` the pin
+you want.
+
+
+See also
+--------
+
+
+-  :ref:`detachInterrupt <lang-detachinterrupt>`
+-  :ref:`external-interrupts`
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/bit.rst b/docs/source/lang/api/bit.rst
new file mode 100644
index 0000000..dd5c050
--- /dev/null
+++ b/docs/source/lang/api/bit.rst
@@ -0,0 +1,44 @@
+.. _lang-bit:
+
+bit()
+=====
+
+(Macro) Computes the value of an (unsigned) integer with the specified
+bit set (``bit(0)`` is 1, ``bit(1)`` is 2, ``bit(2)`` is 4, then 8,
+16, 32, etc.).
+
+Syntax
+------
+
+``bit(n)``
+
+
+Parameters
+----------
+
+* **n** the bit to set.
+
+
+Value
+-----
+
+The value of an integer with the given bit set.
+
+
+Arduino Compatibility
+---------------------
+
+The Maple implementation of bit is compatible with Arduino.
+
+
+See also
+--------
+
+
+-  :ref:`lang-bitread`
+-  :ref:`lang-bitwrite`
+-  :ref:`lang-bitset`
+-  :ref:`lang-bitclear`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/bitclear.rst b/docs/source/lang/api/bitclear.rst
new file mode 100644
index 0000000..941f912
--- /dev/null
+++ b/docs/source/lang/api/bitclear.rst
@@ -0,0 +1,44 @@
+.. _lang-bitclear:
+
+bitClear()
+==========
+
+(Macro) Clears (writes a 0 to) a bit of a numeric variable.
+
+Syntax
+------
+
+``bitClear(x, n)``
+
+
+Parameters
+----------
+
+* **x** the numeric variable whose bit to clear
+
+* **n** which bit to clear, starting at 0 for the least-significant
+  (rightmost) bit
+
+
+Returns
+-------
+
+None.
+
+
+Arduino Compatibility
+---------------------
+
+This implementation is compatible with that of Arduino.
+
+
+See also
+--------
+
+-  :ref:`bit <lang-bit>`\ ()
+-  :ref:`bitRead <lang-bitread>`\ ()
+-  :ref:`bitWrite <lang-bitwrite>`\ ()
+-  :ref:`bitSet <lang-bitset>`\ ()
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/bitread.rst b/docs/source/lang/api/bitread.rst
new file mode 100644
index 0000000..46b4478
--- /dev/null
+++ b/docs/source/lang/api/bitread.rst
@@ -0,0 +1,46 @@
+.. _lang-bitread:
+
+bitRead()
+=========
+
+(Macro) Gets the value of a bit in a number.
+
+
+Syntax
+------
+
+``bitRead(x, n)``
+
+
+Parameters
+----------
+
+* **x** the number from which to read the bit.
+
+* **n** which bit to read, starting at 0 for the least-significant
+  (rightmost) bit
+
+
+Value
+-----
+
+The value of the bit (0 or 1).
+
+
+Arduino Compatibility
+---------------------
+
+The Maple implementation of ``bitRead`` is compatible with Arduino.
+
+
+See also
+--------
+
+
+-  :ref:`lang-bit`
+-  :ref:`lang-bitwrite`
+-  :ref:`lang-bitset`
+-  :ref:`lang-bitclear`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/bitset.rst b/docs/source/lang/api/bitset.rst
new file mode 100644
index 0000000..ccd76de
--- /dev/null
+++ b/docs/source/lang/api/bitset.rst
@@ -0,0 +1,46 @@
+.. _lang-bitset:
+
+bitSet()
+========
+
+(Macro) Sets (writes a 1 to) a bit of a numeric variable.
+
+
+Syntax
+------
+
+``bitSet(x, n)``
+
+
+Parameters
+----------
+
+* **x** the numeric variable whose bit to set
+
+* **n** which bit to set, starting at 0 for the least-significant
+  (rightmost) bit
+
+
+Value
+-----
+
+None.
+
+
+Arduino Compatibility
+---------------------
+
+The Maple implementation of bitSet is compatible with Arduino.
+
+
+See Also
+--------
+
+-  :ref:`lang-bit`
+-  :ref:`lang-bitread`
+-  :ref:`lang-bitwrite`
+-  :ref:`lang-bitclear`
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/bitwrite.rst b/docs/source/lang/api/bitwrite.rst
new file mode 100644
index 0000000..b3feff2
--- /dev/null
+++ b/docs/source/lang/api/bitwrite.rst
@@ -0,0 +1,46 @@
+.. highlight:: cpp
+
+.. _lang-bitwrite:
+
+bitWrite()
+==========
+
+(Macro) Writes a bit of a numeric variable.
+
+Syntax
+------
+
+::
+
+   bitWrite(x, n, b)
+
+Parameters
+----------
+
+**x**: the numeric variable whose bit to write.
+
+**n**: which bit of the number to write, starting at 0 for the
+least-significant (rightmost) bit.
+
+**b**: the value to write to the bit (0 or 1).
+
+Returns
+-------
+
+Nothing.
+
+Arduino Compatibility
+---------------------
+
+Maple's version of ``bitWrite()`` is compatible with Arduino.
+
+See also
+--------
+
+-  :ref:`bit() <lang-bit>`
+-  :ref:`bitRead() <lang-bitRead>`
+-  :ref:`bitSet() <lang-bitSet>`
+-  :ref:`bitClear() <lang-bitClear>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/cc-attribution.txt b/docs/source/lang/api/cc-attribution.txt
new file mode 100644
index 0000000..e100140
--- /dev/null
+++ b/docs/source/lang/api/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/api/constants.rst b/docs/source/lang/api/constants.rst
new file mode 100644
index 0000000..4426293
--- /dev/null
+++ b/docs/source/lang/api/constants.rst
@@ -0,0 +1,327 @@
+.. _lang-constants:
+
+Constants
+=========
+
+Constants are like predefined variables, whose values can't
+change. They are used to make the programs easier to read and modify.
+This page describes the most commonly used constants.
+
+.. contents:: Contents
+   :local:
+
+.. _lang-constants-bool:
+
+Boolean Constants
+-----------------
+
+There are two constants used to represent truth and falsity: ``true``,
+and ``false``.
+
+.. _lang-constants-false:
+
+false
+^^^^^
+
+``false`` is the false ``bool`` value. An integer which is 0 evaluates
+to ``false`` as a boolean.
+
+.. _lang-constants-true:
+
+true
+^^^^
+
+``true`` is the true ``bool`` value.  As an integer, ``true`` is often
+said to be 1.  This is correct in the sense that ``true`` evaluates to
+1 as an integer.  However, any integer which is *non-zero* is ``true``
+as a :ref:`bool <lang-booleanvariables>`. So -1, 2 and -200 are all
+"true", in the sense that these numbers are treated the same as
+``true`` in a boolean context.
+
+Note that the ``true`` and ``false`` constants are typed in lowercase;
+unlike e.g. ``HIGH``, ``LOW``, ``INPUT``, and ``OUTPUT`` (which are
+described below).
+
+
+Pin Levels: HIGH and LOW
+------------------------
+
+When reading or writing to a digital pin there are only two possible
+values a pin can be set to: ``HIGH`` and ``LOW``.
+
+.. _lang-constants-high:
+
+HIGH
+^^^^
+
+The meaning of ``HIGH`` (in reference to a pin) is somewhat different
+depending on whether the pin is set to ``INPUT`` or ``OUTPUT``. When a
+pin is configured as an ``INPUT`` (using :ref:`pinMode()
+<lang-pinmode>`), and read with :ref:`digitalRead()
+<lang-digitalread>`, the microcontroller will report ``HIGH`` if a
+voltage of 3 volts or more is present at the pin.
+
+.. TODO? Following seems false; check it out sometime, leave out for now:
+
+.. A pin may also be configured as an ``INPUT`` with ``pinMode()``, and
+.. subsequently made ``HIGH`` with :ref:`digitalWrite()
+.. <lang-digitalwrite>`, this will set the internal pullup resistors,
+.. which will *steer* the input pin to a HIGH reading unless it is pulled
+.. LOW by external circuitry.
+
+When a pin is configured to ``OUTPUT`` with pinMode, and set to
+``HIGH`` with :ref:`digitalWrite() <lang-digitalwrite>`, the pin is at
+3.3 volts. In this state it can *source* current, e.g. light an LED
+that is connected through a series resistor to ground, or to another
+pin configured as an output and set to ``LOW``.
+
+.. _lang-constants-low:
+
+LOW
+^^^
+
+The meaning of ``LOW`` also has a different meaning depending on
+whether a pin is set to ``INPUT`` or ``OUTPUT``. When a pin is
+configured as an ``INPUT`` with :ref:`pinMode() <lang-pinmode>`, and
+read with :ref:`digitalRead() <lang-digitalread>`, the microcontroller
+will report ``LOW`` if a voltage of 2 volts or less is present at the
+pin.
+
+When a pin is configured to ``OUTPUT`` with ``pinMode()``, and set to
+``LOW`` with :ref:`digitalWrite() <lang-digitalwrite>`, the
+microcontroller will attempt to keep that pin's voltage at 0V. In this
+state it can *sink* current, e.g. light an LED that is connected
+through a series resistor to +3.3V, or to another pin configured as an
+output, and set to ``HIGH``.
+
+Pin Modes
+---------
+
+Digital pins can be used in a variety of modes.  The basic modes,
+``INPUT`` and ``OUTPUT``, have been introduced above.  Changing a pin
+from ``INPUT`` TO ``OUTPUT`` with :ref:`pinMode() <lang-pinmode>`
+drastically changes the electrical behavior of the pin.
+
+This section describes the basic digital pin modes (``INPUT`` and
+``OUTPUT``) only.  For a detailed description of all possible pin
+modes, see the :ref:`pinMode() <lang-pinmode>` reference page.
+
+.. _lang-constants-input:
+
+INPUT
+^^^^^
+
+Maple (STM32) pins configured as ``INPUT`` are said to be in a
+high-impedance state. One way of explaining this is that pins
+configured as ``INPUT`` make extremely small demands on the circuit
+that they are sampling. This makes them useful for reading a sensor,
+but not powering an LED.
+
+.. _lang-constants-output:
+
+OUTPUT
+^^^^^^
+
+Pins configured as ``OUTPUT`` with :ref:`pinMode() <lang-pinmode>` are
+said to be in a low-impedance state. This means that they can provide
+a substantial amount of current to other circuits. STM32 pins can
+source (provide positive current) or sink (provide negative current)
+up to 50 mA (milliamps) of current to other devices/circuits. This
+makes them useful for powering LEDs, but useless for reading sensors.
+
+Pins configured as outputs can also be damaged or destroyed if short
+circuited to either ground or 3.3V power rails. The amount of current
+provided by an STM32 pin is also not enough to power most relays or
+motors, and some interface circuitry will be required.
+
+.. _lang-constants-integers:
+
+Integer Constants
+-----------------
+
+Integer constants (or more properly speaking, integer *literals*) are
+numbers used directly in a sketch, like ``123``. By default, an
+integer literal is treated as a (signed) :ref:`int <lang-int>`, but
+you can change this with the U and L modifiers (see :ref:`below
+<lang-constants-integers-u-l>`).  You can specify negative numbers by
+putting a minus sign in front, like ``-123``.
+
+Normally, integer literals are treated as base 10 (decimal) integers,
+but special notation (formatters) may be used to enter numbers in
+other bases.  These are summarized in the following table:
+
+.. list-table::
+   :header-rows: 1
+
+   * - Base
+     - Example
+     - Formatter
+     - Comment
+
+   * - 10 (decimal)
+     - ``123``
+     - None
+     -
+
+   * - 2 (binary)
+     - ``0b1111011``
+     - Leading "0b"
+     - GCC extension; not standard C++
+
+   * - 8 (octal)
+     - ``0173``
+     - Leading "0"
+     - Characters 0-7 valid
+
+   * - 16 (hexadecimal)
+     - ``0x7B``
+     - Leading "0x"
+     - Characters 0-9, A-F (or a-f) valid
+
+Binary constants (like ``B1111011``) for values between 0 and 255 are
+supported for compatibility with Arduino only.  Their use in new
+programs is discouraged.
+
+.. _lang-constants-integers-dec:
+
+**Decimal** is base 10. This is the common number system we learn in
+school.  Integer literals without other prefixes are assumed to be in
+decimal format.
+
+For example, the decimal literal ``101`` is one hundred and one: 1×10\
+:sup:`2` + 0×10\ :sup:`1` + 1×10\ :sup:`0` = 101.
+
+.. _lang-constants-integers-bin:
+
+**Binary** is base two. Only characters 0 and 1 are valid.  Binary
+literals are indicated by the prefix ``0b`` (this is a :ref:`GCC
+<arm-gcc>` extension; it's not standard C++).
+
+For example, the binary literal ``0b101`` is five: 1×2\ :sup:`2` +
+0×2\ :sup:`1` + 1×2\ :sup:`0` = 5.
+
+.. _lang-constants-integers-oct:
+
+**Octal** is base eight. Only characters 0 through 7 are valid.  Octal
+literals are indicated by the prefix ``0``.
+
+For example, the octal literal ``0101`` is sixty five: 1×8\ :sup:`2` +
+0×8\ :sup:`1` + 1×8\ :sup:`0` = 65.
+
+.. warning:: Bugs sometimes result by (unintentionally) including a
+   leading "0" before an integer literal, which makes the compiler
+   interpret it in octal.
+
+.. _lang-constants-integers-hex:
+
+**Hexadecimal** (or "hex") is base sixteen. Valid characters are 0
+through 9 and letters A through F; A has the value 10, B is 11, up to
+F, which is 15. Hex values are indicated by the prefix ``0x``.  A-F
+may be typed in upper or lower case (a-f).
+
+For example, the hexadecimal literal ``0x101`` is two hundred fifty
+seven: 1×16\ :sup:`2` + 0×16\ :sup:`1` + 1×16\ :sup:`0` = 257.
+
+The hexadecimal literal ``0xCF2`` is three thousand, three hundred
+fourteen: 12×16\ :sup:`2` + 15×16\ :sup:`1` + 2×16\ :sup:`0` = 3314.
+
+(Remember that in hex, ``A`` means 10, and counting up, ``B``\ =11, so
+``C``\ =12 and ``F``\ =15).
+
+.. _lang-constants-integers-u-l:
+
+U and L Suffixes
+^^^^^^^^^^^^^^^^
+
+By default, an integer constant is treated as an :ref:`int
+<lang-int>`, with the attendant :ref:`limitations in values
+<lang-int-overflow>`. To specify an integer constant with another data
+type, follow it with:
+
+- a ``u`` or ``U`` to interpret the constant as an unsigned value.
+  For example, ``33U`` is an :ref:`unsigned int <lang-unsignedint>`.
+
+- an ``l`` or ``L`` to interpret the constant as a long value.  For
+  example, ``100000L`` is a :ref:`long <lang-long>`.
+
+- a ``ul`` or ``UL`` to do both.  For example, ``32767UL`` is an
+  :ref:`unsigned long <lang-unsignedlong>`.
+
+.. _lang-constants-fp:
+
+Floating-Point Constants
+------------------------
+
+Similar to integer literals, floating point constants (properly:
+floating-point *literals*) are used to make code more readable.
+Floating point literals are swapped at compile time for the value to
+which the expression evaluates.
+
+A floating point literal is any number which includes a decimal point.
+For instance, ``3.0`` is a floating-point literal for the number 3.
+By default, a floating-point literal is a :ref:`double <lang-double>`.
+In order for the literal to be interpreted as a :ref:`float
+<lang-float>`, you can write ``f`` directly after it.  For example,
+``3.0f`` is a floating-point literal with type ``float``.
+
+Floating point constants can also be expressed in a variety of
+scientific notation. ``E`` and ``e`` are both accepted as valid
+exponent indicators.  Some examples are given in the following table:
+
+
+.. list-table::
+   :header-rows: 1
+
+   * - Floating-point literal
+     - Evaluates to
+     - Alternate expression
+
+   * - ``10.0``
+     - 10
+     -
+
+   * - ``2.34E5``
+     - 2.34×10\ :sup:`5`
+     - ``234000.0``
+
+   * - ``67e-12``
+     - 67.0×10\ :sup:`-12`
+     - ``0.000000000067``
+
+.. _lang-constants-board:
+
+Board-Specific Constants
+------------------------
+
+This section documents constants whose value might change across
+different LeafLabs boards.  You can use these constants to help ensure
+that your code will be portable across different boards.
+
+.. TODO replace "upcoming" when Mini, Native come out
+
+.. _lang-constants-led:
+
+- ``BOARD_LED_PIN``: the number of the pin which connects to the
+  built-in LED.  On the Maple, this is pin 13, but it's not guaranteed
+  to be the same in upcoming boards like the Maple Mini.
+
+.. _lang-constants-but:
+
+- ``BOARD_BUTTON_PIN``: the number of the pin which connects to the
+  built-in button (labeled "BUT").  On the Maple, this is pin 38, but
+  it's not guaranteed to be the same in other boards.
+
+See Also
+--------
+
+- :ref:`pinMode() <lang-pinmode>`
+- :ref:`Boolean Variables <lang-booleanvariables>`
+- :ref:`#define <lang-define>`
+- :ref:`int <lang-int>`
+- :ref:`unsigned int <lang-unsignedint>`
+- :ref:`long <lang-long>`
+- :ref:`unsigned long <lang-unsignedlong>`
+- :ref:`float <lang-float>`
+- :ref:`double <lang-double>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/constrain.rst b/docs/source/lang/api/constrain.rst
new file mode 100644
index 0000000..d19b61c
--- /dev/null
+++ b/docs/source/lang/api/constrain.rst
@@ -0,0 +1,69 @@
+.. highlight:: cpp
+
+.. _lang-constrain:
+
+constrain()
+===========
+
+(Macro) Constrains a number to be within a range.
+
+Syntax
+------
+
+::
+
+    constrain(x, a, b)
+
+
+Parameters
+----------
+
+**x**: the number to constrain
+
+**a**: the lower end of the range
+
+**b**: the upper end of the range
+
+Returns
+-------
+
+**x**: if **x** is between **a** and **b**
+
+**a**: if **x** is less than **a**
+
+**b**: if **x** is greater than **b**
+
+Example
+-------
+
+::
+
+    // limits range of sensor values to between 10 and 150:
+    sensVal = constrain(sensVal, 10, 150);
+
+
+Warning
+-------
+
+Because of the way ``constrain()`` is implemented, avoid using other
+functions or causing side effects inside the parentheses, as it may
+lead to incorrect results::
+
+    constrain(x,a++,b);   // avoid this - yields incorrect results
+
+    constrain(x,a,b);     // use this instead-
+    a++;                  // keep other math outside constrain()
+
+Arduino Compatibility
+---------------------
+
+Maple's implementation of ``constrain()`` is compatible with Arduino.
+
+See also
+--------
+
+-  :ref:`min() <lang-min>`
+-  :ref:`max() <lang-max>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/cos.rst b/docs/source/lang/api/cos.rst
new file mode 100644
index 0000000..3fbb0af
--- /dev/null
+++ b/docs/source/lang/api/cos.rst
@@ -0,0 +1,32 @@
+.. _lang-cos:
+
+cos()
+=====
+
+Calculates the cosine of an angle.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: cos
+
+Arduino Compatibility
+---------------------
+
+The Maple ``cos()`` implementation is compatible with Arduino.
+
+Note that the Maple implementation comes from `newlib
+<http://sourceware.org/newlib/>`_\ , while Arduino's is that of
+`avr-libc <http://avr-libc.nongnu.org/>`_\ .
+
+See also
+--------
+
+
+-  :ref:`sin() <lang-sin>`
+-  :ref:`tan() <lang-tan>`
+-  :ref:`float <lang-float>`
+-  :ref:`double <lang-double>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/delay.rst b/docs/source/lang/api/delay.rst
new file mode 100644
index 0000000..90ca268
--- /dev/null
+++ b/docs/source/lang/api/delay.rst
@@ -0,0 +1,72 @@
+.. highlight:: cpp
+
+.. _lang-delay:
+
+delay()
+=======
+
+Pauses the program for at least a given number of milliseconds. (There
+are 1000 milliseconds in a second.)
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: delay
+
+
+Discussion
+----------
+
+While it is easy to create a blinking LED with the ``delay()``
+function, and many sketches use short delays for such tasks as switch
+debouncing, the use of ``delay()`` in a sketch has significant
+drawbacks.  No other reading of sensors, mathematical calculations, or
+pin manipulation can go on during the delay function, so in effect, it
+brings most other activity to a halt. For alternative approaches to
+controlling timing see the :ref:`millis() <lang-millis>` function
+and the "Blink Without Delay" sketch cited :ref:`below
+<lang-delay-seealso>`\ . More knowledgeable programmers usually
+avoid the use of ``delay()`` for timing of events longer than tens of
+milliseconds, unless the sketch is very simple.
+
+Certain things *do* go on while the ``delay()`` function is
+controlling the STM32 chip, however, because the delay function does
+not disable interrupts. Serial communication that appears at the RX
+pin is recorded, PWM (see :ref:`pwmWrite() <lang-pwmwrite>`\ ) values
+and pin states are maintained, and :ref:`interrupts
+<lang-attachinterrupt>` will work as they should.
+
+
+Example
+-------
+
+::
+
+    int ledPin = 13;                 // LED connected to pin 13
+
+    void setup() {
+      pinMode(ledPin, OUTPUT);      // sets the digital pin as output
+    }
+
+    void loop() {
+      digitalWrite(ledPin, HIGH);   // sets the LED on
+      delay(1000);                  // waits for a second
+      digitalWrite(ledPin, LOW);    // sets the LED off
+      delay(1000);                  // waits for a second
+    }
+
+.. _lang-delay-seealso:
+
+See also
+--------
+
+
+- :ref:`millis() <lang-millis>`
+- :ref:`micros() <lang-micros>`
+- :ref:`delayMicroseconds() <lang-delayMicroseconds>`
+- (Arduino) `Blink Without Delay
+  <http://arduino.cc/en/Tutorial/BlinkWithoutDelay>`_ example (works
+  unmodified on Maple)
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/delaymicroseconds.rst b/docs/source/lang/api/delaymicroseconds.rst
new file mode 100644
index 0000000..24a8286
--- /dev/null
+++ b/docs/source/lang/api/delaymicroseconds.rst
@@ -0,0 +1,65 @@
+.. highlight:: cpp
+
+.. _lang-delaymicroseconds:
+
+delayMicroseconds()
+===================
+
+Pauses the program for the amount of time (in microseconds)
+specified as parameter. There are a thousand microseconds in a
+millisecond, and a million microseconds in a second.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: delayMicroseconds
+
+
+Example
+-------
+
+The following example configures pin number 8 to work as an output
+pin, and sends a train of pulses with a period of roughly 100
+microseconds::
+
+    int outPin = 8;
+
+    void setup() {
+      pinMode(outPin, OUTPUT);      // sets the digital pin as output
+    }
+
+    void loop() {
+      digitalWrite(outPin, HIGH);   // sets the pin on
+      delayMicroseconds(50);        // pauses for 50 microseconds
+      digitalWrite(outPin, LOW);    // sets the pin off
+      delayMicroseconds(50);        // pauses for 50 microseconds
+    }
+
+
+Caveats and Known Issues
+------------------------
+
+The longest time ``delayMicroseconds()`` can delay is bounded by its
+argument type and the STM32 clock rate to be (2^32 - 1) / 12
+microseconds, or less than 6 minutes.  For longer pauses, use of
+:ref:`lang-delay` is possible.
+
+Arduino Compatibility
+---------------------
+
+While we have made every effort we could to ensure that the timing of
+delayMicroseconds is as accurate as possible, we cannot guarantee it
+will behave as the Arduino implementation down to the microsecond,
+especially for smaller values of ``us``.
+
+See Also
+--------
+
+-  :ref:`millis <lang-millis>`
+-  :ref:`micros <lang-micros>`
+-  :ref:`delay <lang-delay>`
+
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/detachinterrupt.rst b/docs/source/lang/api/detachinterrupt.rst
new file mode 100644
index 0000000..adb2439
--- /dev/null
+++ b/docs/source/lang/api/detachinterrupt.rst
@@ -0,0 +1,37 @@
+.. _lang-detachinterrupt:
+
+detachInterrupt()
+=================
+
+Used to disable an interrupt specified with
+:ref:`lang-attachinterrupt`\ .
+
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: detachInterrupt
+
+Arduino Compatibility
+---------------------
+
+There is one important difference between the Maple version of
+detachInterrupt and the Arduino version.  On the Maple, the argument
+to ``detachInterrupt()`` is the *pin* on which the interrupt is
+attached, while on the Arduino, the argument is the *interrupt
+number*, which is different from the pin the interrupt is enabled on.
+
+If you're calling this function, you've already called
+:ref:`lang-attachinterrupt` to set up your interrupt handler, so
+just call ``detachInterrupt()`` with the same pin argument you gave to
+``attachInterrupt()``.
+
+See Also
+--------
+
+- :ref:`attachInterrupt() <lang-attachInterrupt>`
+
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/digitalread.rst b/docs/source/lang/api/digitalread.rst
new file mode 100644
index 0000000..3502587
--- /dev/null
+++ b/docs/source/lang/api/digitalread.rst
@@ -0,0 +1,58 @@
+.. highlight:: cpp
+
+.. _lang-digitalread:
+
+digitalRead()
+=============
+
+Reads the value from a specified digital pin, either :ref:`HIGH
+<lang-constants-high>` or :ref:`LOW <lang-constants-low>`.
+
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: digitalRead
+
+
+Example
+-------
+
+The following example turns the LED on when the button is pressed::
+
+    int ledPin = 13;     // LED connected to Maple pin 13
+    int buttonPin = 38;  // BUT connected to Maple pin 38
+
+    void setup() {
+      pinMode(ledPin, OUTPUT);
+      pinMode(buttonPin, INPUT);
+    }
+
+    void loop() {
+      int val = digitalRead(buttonPin);   // reads the input pin
+      digitalWrite(ledPin, val);
+    }
+
+Note
+----
+
+If the pin isn't connected to anything, ``digitalRead()`` can return
+either HIGH or LOW (and this can change in a way that seems random).
+
+Arduino Compatibility
+---------------------
+
+The Maple version of ``digitalRead()`` is compatible with Arduino.
+
+
+See Also
+--------
+
+-  :ref:`pinMode <lang-pinMode>`
+-  :ref:`digitalWrite <lang-digitalWrite>`
+
+
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/digitalwrite.rst b/docs/source/lang/api/digitalwrite.rst
new file mode 100644
index 0000000..6124d5f
--- /dev/null
+++ b/docs/source/lang/api/digitalwrite.rst
@@ -0,0 +1,68 @@
+.. highlight:: cpp
+
+.. _lang-digitalwrite:
+
+digitalWrite()
+==============
+
+Write a :ref:`HIGH <lang-constants-high>` or a :ref:`LOW
+<lang-constants-low>` value to a pin configured as :ref:`OUTPUT
+<lang-constants-output>`.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: digitalWrite
+
+Discussion
+----------
+
+If the pin has been configured as an ``OUTPUT`` with :ref:`pinMode()
+<lang-pinmode>` its voltage will be set to the corresponding value:
+3.3V for ``HIGH``, and 0V (ground) for ``LOW``.
+
+.. TODO make the following paragraphs true, but refer the reader to
+.. INPUT_PULLUP and INPUT_PULLDOWN:
+
+If the pin is configured as an ``INPUT``, writing a ``HIGH`` value
+with ``digitalWrite()`` will enable an internal pullup resistor.
+Writing ``LOW`` will disable the pullup. The pullup resistor is enough
+to light an LED dimly, so if LEDs appear to work, but very dimly, this
+is a likely cause. The remedy is to set the pin to an output with the
+:ref:`pinMode() <lang-pinmode>` function.
+
+.. note:: Pin 13 is harder to use as an input than the other pins
+   because it has an LED and resistor soldered to it in series. If you
+   enable its internal pull-up resistor, it will likely hang at around
+   1.1V instead of the expected 3.3V because the onboard LED and
+   series resistor pull the voltage level down. If you must use pin 13
+   as a digital input, use an external pull-down resistor.
+
+Example
+-------
+
+The following example sets pin 13 to ``HIGH``, makes a one-second-long
+delay, sets the pin back to ``LOW``, and delays again, causing a
+blinking pattern::
+
+
+    int ledPin = 13;                 // LED connected to digital pin 13
+
+    void setup() {
+      pinMode(ledPin, OUTPUT);      // sets the digital pin as output
+    }
+
+    void loop() {
+      digitalWrite(ledPin, HIGH);   // sets the LED on
+      delay(1000);                  // waits for a second
+      digitalWrite(ledPin, LOW);    // sets the LED off
+      delay(1000);                  // waits for a second
+    }
+
+See Also
+--------
+
+- :ref:`pinMode <lang-pinmode>`
+- :ref:`digitalRead <lang-digitalread>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/hardwarespi.rst b/docs/source/lang/api/hardwarespi.rst
new file mode 100644
index 0000000..c71b2c3
--- /dev/null
+++ b/docs/source/lang/api/hardwarespi.rst
@@ -0,0 +1,152 @@
+.. highlight:: cpp
+
+.. _lang-hardwarespi:
+
+HardwareSPI
+===========
+
+This class is used for creating objects to manage the Maple's built-in
+SPI ports.  The Maple has two SPI ports.  The relevant pins
+corresponding to each port's logic signals are documented in the
+following table (and on the Maple silkscreen):
+
+.. _lang-hardwarespi-pinout:
+
+.. list-table::
+   :header-rows: 1
+
+   * - Port number
+     - NSS
+     - MOSI
+     - MISO
+     - SCK
+
+   * - 1
+     - 10
+     - 11
+     - 12
+     - 13
+
+   * - 2
+     - 31
+     - 32
+     - 33
+     - 34
+
+If you use a SPI port, you cannot simultaneously use its associated
+pins for other purposes.
+
+Library Documentation
+---------------------
+
+HardwareSPI Class Reference
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+You can use the SPI interface by including a declaration ``HardwareSPI
+Spi(number);`` at the start of the sketch or program.  The ``number``
+must be either 1 or 2 and specifies which port to use.  Once this is
+done, you can call any of the methods documented here using
+``Spi.method(arguments)``; for example, ``Spi.send(0x13)`` would send
+the value ``0x13`` into the port buffer to be transmitted as soon as
+possible.
+
+.. cpp:class:: HardwareSPI
+
+   Class for interacting with SPI.
+
+.. cpp:function:: HardwareSPI::HardwareSPI(uint32 spi_num)
+
+   Construct an object for managing a SPI peripheral.  ``spi_num``
+   must be 1 or 2; see the :ref:`table above
+   <lang-hardwarespi-pinout>` for pinout information.
+
+.. cpp:function:: void HardwareSPI::begin(SPIFrequency freq, uint32 endianness, uint32 mode)
+
+   Configure the baudrate of the given SPI port and set up the header
+   pins appropriately.
+
+   Parameters:
+
+   - ``freq``: one of the ``SPIFrequency`` values, given :ref:`below
+     <lang-hardwarespi-spifrequency>`.
+
+   - ``endianness``: either ``LSBFIRST`` (little-endian) or
+     ``MSBFIRST`` (big-endian).
+
+   - ``mode``: one of 0, 1, 2, or 3, and specifies which SPI mode is
+     used.  The mode number determines a combination of polarity and
+     phase according to the following table:
+
+     .. list-table::
+        :header-rows: 1
+
+        * - Mode
+          - Polarity
+          - Phase
+
+        * - 0
+          - 0
+          - 0
+
+        * - 1
+          - 0
+          - 1
+
+        * - 2
+          - 1
+          - 0
+
+        * - 3
+          - 1
+          - 1
+
+     For more information on polarity and phase, see the
+     :ref:`external references, below <lang-hardwarespi-seealso>`.
+
+.. cpp:function:: void HardwareSPI::begin()
+
+   A convenience ``begin()``, equivalent to ``begin(SPI_1_125MHZ,
+   MSBFIRST, 0)``.
+
+.. cpp:function:: uint8 HardwareSpi::send(uint8 *data, uint32 length)
+
+   Writes ``data`` into the port buffer to be transmitted as soon as
+   possible, where ``length`` is the number of bytes to send from
+   ``data``.  Returns the last byte shifted back from slave.
+
+.. cpp:function:: uint8 HardwareSpi::send(uint8 data)
+
+   Writes the single byte ``data`` into the port buffer to be
+   transmitted as soon as possible.  Returns the data byte shifted
+   back from the slave.
+
+.. cpp:function:: uint8 HardwareSpi::recv()
+
+   Reads a byte from the peripheral.  Returns the next byte in the
+   buffer.
+
+SPI Speeds
+^^^^^^^^^^
+
+.. _lang-hardwarespi-spifrequency:
+
+The possible SPI speeds are configured using the ``SPIFrequency`` enum:
+
+.. doxygenenum:: SPIFrequency
+
+.. _lang-hardwarespi-seealso:
+
+See Also
+--------
+
+* `Wikipedia Article on Serial Peripheral Interface Bus (SPI)
+  <http://en.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus>`_
+* `Arduino reference on SPI
+  <http://www.arduino.cc/playground/Code/Spi>`_
+* `Hardcore SPI on Arduino <http://klk64.com/arduino-spi/>`_ by kik64
+* STMicro documentation for STM32F103RB microcontroller:
+
+  * `Datasheet <http://www.st.com/stonline/products/literature/ds/13587.pdf>`_ (pdf)
+  * `Reference Manual <http://www.st.com/stonline/products/literature/rm/13902.pdf>`_ (pdf)
+
+
diff --git a/docs/source/lang/api/hardwaretimer.rst b/docs/source/lang/api/hardwaretimer.rst
new file mode 100644
index 0000000..258471b
--- /dev/null
+++ b/docs/source/lang/api/hardwaretimer.rst
@@ -0,0 +1,368 @@
+.. highlight:: cpp
+
+.. _lang-hardwaretimer:
+
+HardwareTimer
+=============
+
+This class defines the public API for interfacing with the STM32's
+built-in timer peripherals.  More information on these peripherals
+(including code examples) is available in the :ref:`timers reference
+<timers>`.
+
+Library Documentation
+---------------------
+
+HardwareTimer Class Reference
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+To interact with a particular timer, call one of the methods
+documented below on one of the predefined ``HardwareTimer`` instances.
+For example, to set the prescale factor on timer 1 to 5, call
+``Timer1.setPrescaleFactor(5)``.
+
+.. cpp:class:: HardwareTimer
+
+   Class for interacting with a timer.  There are four predefined
+   instances available on the Maple: ``Timer1``, ``Timer2``,
+   ``Timer3``, and ``Timer4``.
+
+.. _lang-hardwaretimer-attachinterrupt:
+
+.. cpp:function:: void HardwareTimer::attachInterrupt(int channel, voidFuncPtr handler)
+
+   Attach an interrupt handler to the given ``channel``.  This
+   interrupt handler will be called when the timer's counter reaches
+   the given channel :ref:`compare <lang-hardwaretimer-setcompare>`
+   value.
+
+   ``handler`` should be a function which takes no arguments and has
+   :ref:`void <lang-void>` value; i.e. it should have signature ::
+
+       void handler(void);
+
+   You can later detach the interrupt using :ref:`detachInterrupt()
+   <lang-hardwaretimer-detachinterrupt>`.
+
+   .. note:: The function (often called an *interrupt service
+             routine*, or ISR) should attempt to return as quickly as
+             possible.  :ref:`Blinking the LED <lang-toggleled>`, some
+             logic, :ref:`PWM <pwm>` updates, and :ref:`Serial
+             <lang-serial>` writes are fine; writing to
+             :ref:`SerialUSB <lang-serialusb>` or :ref:`waiting
+             <lang-waitforbuttonpress>` for user input can take a long
+             time and prevent other interrupts from firing on time.
+
+             Tip: if you have a :ref:`delay() <lang-delay>` in your
+             ISR, you're probably doing it wrong.
+
+.. cpp:function:: void HardwareTimer::attachCompare1Interrupt(voidFuncPtr handler)
+
+   Equivalent to :ref:`attachInterrupt
+   <lang-hardwaretimer-attachinterrupt>`\ ``(1, handler)``.
+
+.. cpp:function:: void HardwareTimer::attachCompare2Interrupt(voidFuncPtr handler)
+
+   Equivalent to :ref:`attachInterrupt
+   <lang-hardwaretimer-attachinterrupt>`\ ``(2, handler)``.
+
+.. cpp:function:: void HardwareTimer::attachCompare3Interrupt(voidFuncPtr handler)
+
+   Equivalent to :ref:`attachInterrupt
+   <lang-hardwaretimer-attachinterrupt>`\ ``(3, handler)``.
+
+.. cpp:function:: void HardwareTimer::attachCompare4Interrupt(voidFuncPtr handler)
+
+   Equivalent to :ref:`attachInterrupt
+   <lang-hardwaretimer-attachinterrupt>`\ ``(4, handler)``.
+
+.. _lang-hardwaretimer-setchannelmode:
+
+.. cpp:function:: void HardwareTimer::setChannelMode(int channel, TimerMode mode)
+
+   Set the given channel of this timer to the given :ref:`mode
+   <lang-hardwaretimer-modes>`.  The parameter ``channel`` is one of
+   1, 2, 3, and 4, and corresponds to the compare channel you would
+   like to set.  Refer to the full :ref:`pin mapping table
+   <pin-mapping-mega-table>` to match up timer channels and pin
+   numbers.
+
+.. cpp:function:: void HardwareTimer::setChannel1Mode(TimerMode mode)
+
+   Equivalent to :ref:`setChannelMode <lang-hardwaretimer-setchannelmode>`\
+   ``(1, mode)``.
+
+.. cpp:function:: void HardwareTimer::setChannel2Mode(TimerMode mode)
+
+   Equivalent to :ref:`setChannelMode <lang-hardwaretimer-setchannelmode>`\
+   ``(2, mode)``.
+
+.. cpp:function:: void HardwareTimer::setChannel3Mode(TimerMode mode)
+
+   Equivalent to :ref:`setChannelMode <lang-hardwaretimer-setchannelmode>`\
+   ``(3, mode)``.
+
+.. cpp:function:: void HardwareTimer::setChannel4Mode(TimerMode mode)
+
+   Equivalent to :ref:`setChannelMode <lang-hardwaretimer-setchannelmode>`\
+   ``(4, mode)``.
+
+.. _lang-hardwaretimer-getcompare:
+
+.. cpp:function:: uint16 HardwareTimer::getCompare(int channel)
+
+   Gets the compare value for the given ``channel``, from 1 to 4.  See
+   :ref:`setCompare() <lang-hardwaretimer-setcompare>`.
+
+.. cpp:function:: uint16 HardwareTimer::getCompare1()
+
+   Equivalent to :ref:`getCompare <lang-hardwaretimer-getcompare>`\
+   ``(1, mode)``.
+
+.. cpp:function:: uint16 HardwareTimer::getCompare2()
+
+   Equivalent to :ref:`getCompare <lang-hardwaretimer-getcompare>`\
+   ``(2, mode)``.
+
+.. cpp:function:: uint16 HardwareTimer::getCompare3()
+
+   Equivalent to :ref:`getCompare <lang-hardwaretimer-getcompare>`\
+   ``(3, mode)``.
+
+.. cpp:function:: uint16 HardwareTimer::getCompare4()
+
+   Equivalent to :ref:`getCompare <lang-hardwaretimer-getcompare>`\
+   ``(4, mode)``.
+
+.. _lang-hardwaretimer-setcompare:
+
+.. cpp:function:: void HardwareTimer::setCompare(int channel, uint16 compare)
+
+   Sets the compare value for the given ``channel`` to ``compare``.
+   If ``compare`` is greater than this timer's overflow value, it will
+   be truncated to the overflow value.  The default compare value is
+   65,535 (the largest unsigned 16-bit integer value).
+
+   When the counter reaches this value the interrupt for this channel
+   will fire if the given ``channel`` :ref:`mode
+   <lang-hardwaretimer-setchannelmode>` is ``TIMER_OUTPUTCOMPARE`` and
+   an interrupt is :ref:`attached
+   <lang-hardwaretimer-attachinterrupt>`.
+
+   By default, this only changes the relative offsets between events
+   on a single timer ("phase"); they don't control the frequency with
+   which they occur. However, a common trick is to increment the
+   compare value manually in the interrupt handler so that the event
+   will fire again after the increment period. There can be a
+   different increment value for each channel, so this trick allows
+   events to be programmed at 4 different rates on a single
+   timer. Note that function call overheads mean that the smallest
+   increment rate is at least a few microseconds.
+
+.. cpp:function:: void HardwareTimer::setCompare1(uint16 compare)
+
+   Equivalent to :ref:`setCompare <lang-hardwaretimer-setcompare>`\
+   ``(1, compare)``.
+
+.. cpp:function:: void HardwareTimer::setCompare2(uint16 compare)
+
+   Equivalent to :ref:`setCompare <lang-hardwaretimer-setcompare>`\
+   ``(2, compare)``.
+
+.. cpp:function:: void HardwareTimer::setCompare3(uint16 compare)
+
+   Equivalent to :ref:`setCompare <lang-hardwaretimer-setcompare>`\
+   ``(3, compare)``.
+
+.. cpp:function:: void HardwareTimer::setCompare4(uint16 compare)
+
+   Equivalent to :ref:`setCompare <lang-hardwaretimer-setcompare>`\
+   ``(4, compare)``.
+
+.. cpp:function:: uint16 HardwareTimer::getCount()
+
+   Gets the current timer count.  Due to function call overhead, the
+   return value will be increasingly accurate with smaller prescale
+   values.  Also see :ref:`setCount() <lang-hardwaretimer-setcount>`.
+
+.. _lang-hardwaretimer-setcount:
+
+.. cpp:function:: void HardwareTimer::setCount(uint16 val)
+
+    Set the timer's current count to ``val``.
+
+    Note that there is some function call overhead associated with
+    calling this method, so using it is not a robust way to get
+    multiple timers to share a count value.
+
+    If ``val`` exceeds the timer's :ref:`overflow value
+    <lang-hardwaretimer-getoverflow>`, it is truncated to the overflow
+    value.
+
+
+.. _lang-hardwaretimer-detachinterrupt:
+
+.. cpp:function:: void HardwareTimer::detachInterrupt(int channel)
+
+   Remove the interrupt handler attached to the given ``channel``, if
+   any.  The handler will no longer be called by this timer.
+
+.. cpp:function:: void HardwareTimer::detachCompare1Interrupt()
+
+   Equivalent to :ref:`detachInterrupt
+   <lang-hardwaretimer-detachinterrupt>`\ ``(1)``.
+
+.. cpp:function:: void HardwareTimer::detachCompare2Interrupt()
+
+   Equivalent to :ref:`detachInterrupt
+   <lang-hardwaretimer-detachinterrupt>`\ ``(2)``.
+
+.. cpp:function:: void HardwareTimer::detachCompare3Interrupt()
+
+   Equivalent to :ref:`detachInterrupt
+   <lang-hardwaretimer-detachinterrupt>`\ ``(3)``.
+
+.. cpp:function:: void HardwareTimer::detachCompare4Interrupt()
+
+   Equivalent to :ref:`detachInterrupt
+   <lang-hardwaretimer-detachinterrupt>`\ ``(4)``.
+
+.. _lang-hardwaretimer-generateupdate:
+
+.. cpp:function:: void HardwareTimer::generateUpdate()
+
+   Re-initializes the counter (to 0 in upcounting mode, which is the
+   default), and generates an update of the prescale and overflow
+   registers.
+
+.. _lang-hardwaretimer-getoverflow:
+
+.. cpp:function:: uint16 HardwareTimer::getOverflow()
+
+   Gets the timer's overflow value.  See :ref:`setOverflow()
+   <lang-hardwaretimer-setoverflow>`.
+
+.. _lang-hardwaretimer-setoverflow:
+
+.. cpp:function:: void HardwareTimer::setOverflow(uint16 val)
+
+    Sets the timer overflow (or "reload") value to ``val``.
+
+    When the timer's counter reaches this, value it resets to
+    zero. Its default value is 65535 (the largest unsigned 16-bit
+    integer); setting the overflow to anything lower will cause
+    interrupts to be called more frequently (see :ref:`setPeriod()
+    <lang-hardwaretimer-setperiod>` function for a shortcut).
+
+    After the next :ref:`timer update
+    <lang-hardwaretimer-generateupdate>`, this number will be the
+    maximum value for the timer's channel compare values.
+
+.. _lang-hardwaretimer-pause:
+
+.. cpp:function:: void HardwareTimer::pause()
+
+   Stop the timer's counter, without affecting its configuration.
+
+   The timer will no longer count or fire interrupts after this
+   function is called, until it is resumed.  This function is useful
+   during timer setup periods, in order to prevent interrupts from
+   firing before the timer is fully configured.
+
+   Note that there is some function call overhead associated with this
+   method, so using it in concert with :ref:`resume()
+   <lang-hardwaretimer-resume>` is not a robust way to align multiple
+   timers to the same count value.
+
+.. _lang-hardwaretimer-setperiod:
+
+.. cpp:function:: uint16 HardwareTimer::setPeriod(uint32 microseconds)
+
+   Configure the :ref:`prescaler
+   <lang-hardwaretimer-getprescalefactor>` and :ref:`overflow
+   <lang-hardwaretimer-getoverflow>` values to generate a timer reload
+   with a period as close to the given number of ``microseconds`` as
+   possible.
+
+   The return value is the new overflow value, which may be used to
+   set channel compare values.  However, if a clock that fires an
+   interrupt every given number of microseconds is all that is
+   desired, and the relative "phases" are unimportant, channel compare
+   values may all be set to 1.
+
+.. _lang-hardwaretimer-getprescalefactor:
+
+.. cpp:function:: uint16 HardwareTimer::getPrescaleFactor()
+
+    Returns the timer's prescale factor.  See
+    :ref:`setPrescaleFactor() <lang-hardwaretimer-setprescalefactor>`.
+
+.. _lang-hardwaretimer-setprescalefactor:
+
+.. cpp:function:: void HardwareTimer::setPrescaleFactor(uint16 factor)
+
+    Set the timer's prescale factor to ``factor``.
+
+    The prescaler acts as a clock divider to slow down the rate at
+    which the counter increments.
+
+    For example, the system clock rate is 72MHz, so the counter will
+    reach 65535 in (13.89 nanoseconds) × (65535 counts) = (910.22
+    microseconds), or about a thousand times a second. If the
+    prescaler equals 1098, then the clock rate is effectively 72MHz /
+    1098 = 65.56KHz, and the counter will reach 65536 in (15.25
+    microseconds) × (65536 counts) = (0.999 seconds), or about once
+    per second.
+
+    The :ref:`setPeriod() <lang-hardwaretimer-setperiod>` method may
+    also be used as a convenient alternative.
+
+.. cpp:function:: void HardwareTimer::resume()
+
+    Resume a paused timer, without affecting its configuration.
+
+    The timer will resume counting and firing interrupts as
+    appropriate.
+
+    Note that there is some function call overhead associated with
+    using this method, so using it in concert with :ref:`pause()
+    <lang-hardwaretimer-pause>` is not a robust way to align multiple
+    timers to the same count value.
+
+.. cpp:function:: timer_dev_num HardwareTimer::getTimerNum()
+
+   Returns the :ref:`timer device number
+   <lang-hardwaretimer-timer-dev-num>` associated with the timer.  For
+   example, ``Timer1.getTimerNum()`` would return ``TIMER1``.
+
+   In most cases, you should not need to use this function.  If you do
+   use it, be careful; the constant ``TIMER1`` is *not equal* to the
+   number 1; similarly, ``TIMER2`` is *not* the number 2, etc.  Be
+   sure to refer to the timer device number by name.
+
+.. _lang-hardwaretimer-modes:
+
+Timer Modes
+^^^^^^^^^^^
+.. doxygenenum:: TimerMode
+
+.. _lang-hardwaretimer-timer-dev-num:
+
+Timer Device Numbers
+^^^^^^^^^^^^^^^^^^^^
+
+These provide a lower-level interface for interacting with timers.
+They are mostly useful in context with the :ref:`getTimer()
+<lang-hardwaretimer-gettimer>` function.  **Be careful** when using
+these not to confuse e.g. ``TIMER1`` with the number 1; they are
+different.
+
+.. doxygenenum:: timer_dev_num
+
+.. _lang-hardwaretimer-convenience:
+
+.. _lang-hardwaretimer-gettimer:
+
+Other Functions
+^^^^^^^^^^^^^^^
+.. doxygenfunction:: getTimer
diff --git a/docs/source/lang/api/highbyte.rst b/docs/source/lang/api/highbyte.rst
new file mode 100644
index 0000000..50a1fa6
--- /dev/null
+++ b/docs/source/lang/api/highbyte.rst
@@ -0,0 +1,59 @@
+.. highlight:: cpp
+
+.. _lang-highbyte:
+
+highByte()
+==========
+
+(Macro) Extracts the second lowest byte of an integral data type.
+
+.. warning:: This macro is provided for compatibility with Arduino
+   only.  It returns the second-least significant byte in an integral
+   value.  It makes sense to call this the "high" byte on a 16-bit
+   ``int`` microcontroller like the Atmel chips on Arduinos, but it
+   makes no sense at all on a 32-bit microcontroller like the STM32s
+   in the Maple line.
+
+   In short: we provide this so that existing Arduino code works as
+   expected, but **strongly discourage its use** in new programs.
+
+Syntax
+------
+
+::
+
+  highByte(x)
+
+Parameters
+----------
+
+**x**: a value of any integral type.
+
+Returns
+-------
+
+Second lowest byte in **x**.
+
+Example
+-------
+
+::
+
+    int x = 0xDEADBEEF;
+    SerialUSB.println(x, HEX); // prints "BE"
+
+Arduino Compatibility
+---------------------
+
+The Maple version of ``highByte()`` is compatible with Arduino.
+
+See Also
+--------
+
+-  :ref:`lowByte() <lang-lowbyte>`
+
+
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/interrupts.rst b/docs/source/lang/api/interrupts.rst
new file mode 100644
index 0000000..58fd2cc
--- /dev/null
+++ b/docs/source/lang/api/interrupts.rst
@@ -0,0 +1,47 @@
+.. highlight:: cpp
+
+.. _lang-interrupts:
+
+interrupts()
+============
+
+Re-enables interrupts (after they've been disabled by
+:ref:`noInterrupts() <lang-nointerrupts>`).  Interrupts allow certain
+important tasks to happen in the background, and certain interrupts
+are enabled by default.
+
+Some functions will not work while interrupts are disabled, and both
+incoming and outgoing communication may be ignored. Interrupts can
+slightly disrupt the timing of code, however, and may be disabled for
+particularly critical sections of code.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: interrupts
+
+Example
+-------
+
+::
+
+    void setup() {}
+
+    void loop() {
+      noInterrupts();
+      // critical, time-sensitive code here
+      interrupts();
+      // other code here
+    }
+
+See Also
+--------
+
+- :ref:`noInterrupts() <lang-nointerrupts>`
+- :ref:`attachInterrupt() <lang-attachinterrupt>`
+- :ref:`detachInterrupt() <lang-detachinterrupt>`
+- :ref:`Timers reference <timers>`
+- :ref:`Timer API <lang-hardwaretimer>`
+- :ref:`External interrupts <external-interrupts>`
+
+.. include:: /lang/cc-attribution.txt
diff --git a/docs/source/lang/api/isbuttonpressed.rst b/docs/source/lang/api/isbuttonpressed.rst
new file mode 100644
index 0000000..dbff0c9
--- /dev/null
+++ b/docs/source/lang/api/isbuttonpressed.rst
@@ -0,0 +1,17 @@
+.. _lang-isbuttonpressed:
+
+isButtonPressed()
+=================
+
+Check whether the board's built-in button (labeled BUT on the
+silkscreen) is pressed.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: isButtonPressed
+
+See Also
+--------
+
+- :ref:`lang-waitforbuttonpress`
diff --git a/docs/source/lang/api/loop.rst b/docs/source/lang/api/loop.rst
new file mode 100644
index 0000000..d8f6183
--- /dev/null
+++ b/docs/source/lang/api/loop.rst
@@ -0,0 +1,45 @@
+.. highlight:: cpp
+
+.. _lang-loop:
+
+loop()
+======
+
+After creating a :ref:`setup() <lang-setup>` function, which
+initializes your sketch, the ``loop()`` function gets called
+repeatedly, allowing your program to change and respond.  Use it to
+actively control your Maple board.
+
+Example
+-------
+
+::
+
+
+    int buttonPin = 38;
+
+    // setup initializes serial and the button pin
+    void setup() {
+      SerialUSB.begin();
+      pinMode(buttonPin, INPUT);
+    }
+
+    // loop() checks the button pin each time it executes,
+    // and will print 'H' if it is pressed, 'L' otherwise
+    void loop() {
+      if (digitalRead(buttonPin) == HIGH) {
+        SerialUSB.println('H');
+      } else {
+        SerialUSB.println('L');
+      }
+
+      delay(1000);
+    }
+
+See Also
+--------
+
+- :ref:`setup() <lang-setup>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/lowbyte.rst b/docs/source/lang/api/lowbyte.rst
new file mode 100644
index 0000000..58e622f
--- /dev/null
+++ b/docs/source/lang/api/lowbyte.rst
@@ -0,0 +1,25 @@
+.. _lang-lowbyte:
+
+lowByte()
+=========
+
+Extracts the low-order (rightmost) byte of a variable (e.g. a
+word).
+
+Syntax
+------
+
+lowByte(x)
+
+Parameters
+----------
+
+**x**: a value of any type.  However, if a non-integral type is used,
+the results will be strange.
+
+Returns
+-------
+
+The low byte's value (this will be between 0 and 255).
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/map.rst b/docs/source/lang/api/map.rst
new file mode 100644
index 0000000..79122b3
--- /dev/null
+++ b/docs/source/lang/api/map.rst
@@ -0,0 +1,68 @@
+.. highlight:: cpp
+
+.. _lang-map:
+
+map()
+=====
+
+Re-maps a number from one range to another.
+
+.. contents:: Contents
+   :local:
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: map
+
+Discussion
+----------
+
+``map()`` does not constrain values to within the range, because
+out-of-range values are sometimes intended and useful. The
+:ref:`constrain() <lang-constrain>` macro may be used either before or
+after this function, if limits to the ranges are desired.
+
+Note that the "lower bounds" of either range may be larger or smaller
+than the "upper bounds" so that ``map()`` may be used to reverse a
+range of numbers; for example::
+
+    y = map(x, 1, 50, 50, 1);
+
+The function also handles negative numbers well, so that this
+example ::
+
+    y = map(x, 1, 50, 50, -100);
+
+is also valid.
+
+The ``map()`` function uses integer math (its arguments and return
+values all have type :ref:`long <lang-long>`), so it will not generate
+fractions, when the math might indicate that it should do so.
+Fractional remainders are truncated, and are not rounded or averaged.
+
+Example
+-------
+
+::
+
+    /* Map an ADC reading (12 bits) to 16-bit PWM (0 to 65,535) */
+
+    void setup() {
+        pinMode(0, INPUT_ANALOG);
+        pinMode(9, PWM);
+    }
+
+    void loop() {
+        int val = analogRead(0);
+        val = map(val, 0, 4095, 0, 65535);
+        analogWrite(9, val);
+    }
+
+
+See Also
+--------
+
+-  :ref:`constrain() <lang-constrain>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/max.rst b/docs/source/lang/api/max.rst
new file mode 100644
index 0000000..d38eebe
--- /dev/null
+++ b/docs/source/lang/api/max.rst
@@ -0,0 +1,65 @@
+.. highlight:: cpp
+
+.. _lang-max:
+
+max()
+=====
+
+(Macro) Calculates the maximum of two numbers.
+
+Syntax
+------
+
+::
+
+    max(x, y)
+
+Parameters
+----------
+
+**x**: the first number; may be any number or numeric expression.
+
+**y**: the second number; may be any number or numeric expression.
+
+
+Returns
+-------
+
+The larger of the two parameter values.
+
+Example
+-------
+
+::
+
+    sensVal = max(senVal, 20); // assigns sensVal to the larger of sensVal or 20
+                               // (effectively ensuring that it is at least 20)
+
+.. note:: Perhaps counter-intuitively, max() is often used to
+   constrain the lower end of a variable's range, while :ref:`min()
+   <lang-min>` is used to constrain the upper end of the range.
+
+Warning
+-------
+
+Because of the way ``max()`` is implemented, avoid using other
+functions inside the parentheses.  It may lead to incorrect results::
+
+    max(a--, 0);   // avoid this - yields incorrect results
+
+    a--;           // use this instead -
+    max(a, 0);     // keep other operations outside max()
+
+Arduino Compatibility
+---------------------
+
+The Maple version of ``max()`` is compatible with Arduino.
+
+See Also
+--------
+
+-  :ref:`min() <lang-min>`
+-  :ref:`constrain() <lang-constrain>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/micros.rst b/docs/source/lang/api/micros.rst
new file mode 100644
index 0000000..f12976b
--- /dev/null
+++ b/docs/source/lang/api/micros.rst
@@ -0,0 +1,46 @@
+.. highlight:: cpp
+
+.. _lang-micros:
+
+micros()
+========
+
+Returns the number of microseconds since the Maple board began running
+the current program. This number will overflow (go back to zero),
+after approximately 70 minutes.
+
+.. note:: There are 1,000 microseconds in a millisecond, and 1,000,000
+   microseconds in a second.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: micros
+
+Example
+-------
+
+::
+
+    unsigned int time;
+
+    void setup() {
+    }
+
+    void loop() {
+      SerialUSB.print("Time: ");
+      time = micros();
+      // prints time since program started
+      SerialUSB.println(time);
+      // wait a second so as not to send massive amounts of data
+      delay(1000);
+    }
+
+See Also
+--------
+
+-  :ref:`millis() <lang-millis>`
+-  :ref:`delay() <lang-delay>`
+-  :ref:`delayMicroseconds() <lang-delaymicroseconds>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/millis.rst b/docs/source/lang/api/millis.rst
new file mode 100644
index 0000000..54e4507
--- /dev/null
+++ b/docs/source/lang/api/millis.rst
@@ -0,0 +1,52 @@
+.. highlight:: cpp
+
+.. _lang-millis:
+
+millis()
+========
+
+Returns the number of milliseconds since the Maple board began running
+the current program. This number will overflow (go back to zero) after
+approximately 50 days.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: millis
+
+Example
+-------
+
+The following time prints the value returned by ``millis()`` roughly
+once per second::
+
+    unsigned int time;
+
+    void setup() {
+    }
+
+    void loop() {
+      SerialUSB.print("Time: ");
+      time = millis();
+      // prints time since program started
+      Serial.println(time);
+
+      // wait a second so as not to send massive amounts of data
+      delay(1000);
+    }
+
+Tip
+---
+
+Since the return value for ``millis()`` is an :ref:`unsigned long
+<lang-unsignedlong>`, overflow errors may occur if you try to do math
+with other data types, such as :ref:`ints <lang-int>`.
+
+See Also
+--------
+
+- :ref:`micros <lang-micros>`
+- :ref:`delay <lang-delay>`
+- :ref:`delayMicroseconds <lang-delaymicroseconds>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/min.rst b/docs/source/lang/api/min.rst
new file mode 100644
index 0000000..1245f6f
--- /dev/null
+++ b/docs/source/lang/api/min.rst
@@ -0,0 +1,66 @@
+.. highlight:: cpp
+
+.. _lang-min:
+
+min()
+=====
+
+(Macro) Calculates the minimum of two numbers.
+
+Syntax
+------
+
+::
+
+    min(x,y)
+
+Parameters
+----------
+
+**x**: the first number; may be any number or numeric expression.
+
+**y**: the second number; may be any number or numeric expression.
+
+Returns
+-------
+
+The smaller of the two numbers.
+
+Example
+-------
+
+::
+
+    sensVal = min(sensVal, 100); // assigns sensVal to the smaller of sensVal or 100
+                                 // ensuring that it never gets above 100.
+
+
+.. note:: Perhaps counter-intuitively, max() is often used to
+   constrain the lower end of a variable's range, while min() is used
+   to constrain the upper end of the range.
+
+
+Warning
+-------
+
+Because of the way ``min()`` is implemented, avoid using other
+functions inside the parentheses. It may lead to incorrect results::
+
+    min(a++, 100);   // avoid this - yields incorrect results
+
+    a++;            // use this instead -
+    min(a, 100);    // keep other operations outside min()
+
+Arduino Compatibility
+---------------------
+
+The Maple version of ``min()`` is compatible with Arduino.
+
+See Also
+--------
+
+-  :ref:`max() <lang-max>`
+-  :ref:`constrain() <lang-constrain>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/nointerrupts.rst b/docs/source/lang/api/nointerrupts.rst
new file mode 100644
index 0000000..68f0498
--- /dev/null
+++ b/docs/source/lang/api/nointerrupts.rst
@@ -0,0 +1,47 @@
+.. highlight:: cpp
+
+.. _lang-nointerrupts:
+
+noInterrupts()
+==============
+
+Description
+-----------
+
+Disables interrupts.  Interrupts allow certain important tasks to
+happen in the background and are enabled by default. Some functions
+will not work while interrupts are disabled, and incoming
+communication may be ignored. Interrupts can slightly disrupt the
+timing of code, however, and may be disabled for particularly critical
+sections of code.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: noInterrupts
+
+Example
+-------
+
+::
+
+    void setup() {}
+
+    void loop() {
+      noInterrupts();
+      // critical, time-sensitive code here
+      interrupts();
+      // other code here
+    }
+
+See Also
+--------
+
+- :ref:`interrupts() <lang-interrupts>`
+- :ref:`attachInterrupt() <lang-attachinterrupt>`
+- :ref:`detachInterrupt() <lang-detachinterrupt>`
+- :ref:`Timers reference <timers>`
+- :ref:`Timer API <lang-hardwaretimer>`
+- :ref:`External interrupts <external-interrupts>`
+
+.. include:: /lang/cc-attribution.txt
diff --git a/docs/source/lang/api/pinmode.rst b/docs/source/lang/api/pinmode.rst
new file mode 100644
index 0000000..03cbcfa
--- /dev/null
+++ b/docs/source/lang/api/pinmode.rst
@@ -0,0 +1,79 @@
+.. highlight:: cpp
+
+.. _lang-pinmode:
+
+pinMode()
+=========
+
+.. contents:: Contents
+   :local:
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: pinMode
+
+.. _lang-pinmode-wiringpinmode:
+
+.. doxygenenum:: WiringPinMode
+
+Discussion
+----------
+
+``pinMode()`` is usually called within :ref:`lang-setup` in order to
+configure a pin for a certain usage (although it may be called
+anywhere).
+
+Example
+-------
+
+::
+
+    int ledPin = 13;                 // LED connected to digital pin 13
+
+    void setup() {
+      pinMode(ledPin, OUTPUT);      // sets the digital pin as output
+    }
+
+    void loop() {
+      digitalWrite(ledPin, HIGH);   // sets the LED on
+      delay(1000);                  // waits for a second
+      digitalWrite(ledPin, LOW);    // sets the LED off
+      delay(1000);                  // waits for a second
+    }
+
+Arduino Compatibility
+---------------------
+
+.. TODO check out Arduino vs. Maple static discilpline cutoffs to
+.. ensure accuracy of following:
+
+The libmaple implementation of ``pinMode()`` supports the ``INPUT``
+and ``OUTPUT`` modes with semantics identical to that of the Arduino
+function (however, be advised that the Maple, as a 3.3V device, will
+only drive 3.3V to an ``OUTPUT`` pin that has been set ``HIGH``).
+
+``INPUT_ANALOG`` and ``PWM`` modes were added because the Maple does
+not distinguish between analog and digital pins the same way the
+Arduino does.  Unlike the Arduino, you **must call** ``pinMode()`` to
+set up a pin for these purposes before a call to, e.g.,
+:ref:`lang-analogRead`.  In practice, this should only add a few lines
+to your :ref:`lang-setup` function.
+
+.. TODO verify following before putting it in:
+
+.. ``OUTPUT_OPEN_DRAIN``, ``INPUT_PULLUP``, ``INPUT_PULLDOWN``, and
+.. ``PWM_OPEN_DRAIN`` modes represent functionality not currently
+.. available on Arduino boards.
+
+See also
+--------
+
+-  :ref:`lang-constants`
+-  :ref:`lang-digitalwrite`
+-  :ref:`lang-digitalread`
+-  Maple :ref:`GPIO <gpio>` reference page
+
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/pow.rst b/docs/source/lang/api/pow.rst
new file mode 100644
index 0000000..4280400
--- /dev/null
+++ b/docs/source/lang/api/pow.rst
@@ -0,0 +1,23 @@
+.. _lang-pow:
+
+pow()
+=====
+
+Calculates the value of a number raised to a power.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: pow
+
+.. TODO LATER some examples
+
+See Also
+--------
+
+-  :ref:`sqrt() <lang-sqrt>`
+-  :ref:`float <lang-float>`
+-  :ref:`double <lang-double>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/pwmwrite.rst b/docs/source/lang/api/pwmwrite.rst
new file mode 100644
index 0000000..2c858ab
--- /dev/null
+++ b/docs/source/lang/api/pwmwrite.rst
@@ -0,0 +1,56 @@
+.. highlight:: cpp
+
+.. _lang-pwmwrite:
+
+pwmWrite()
+==========
+
+Writes a :ref:`PWM wave <pwm>` to a pin.  You can use this to make an
+LED get brighter or dimmer, control a servomotor, etc. After a call to
+pwmWrite(), the pin will output a steady square wave with the given
+duty cycle.  You can change the duty cycle later by calling pwmWrite()
+again with the same pin and a different duty.
+
+On the Maple, the pins which support PWM are: 0, 1, 2, 3, 5, 6, 7, 8,
+9, 11, 12, 14, 24, 27, and 28.
+
+The Arduino function :ref:`analogWrite() <lang-analogwrite>` is an
+alias for ``pwmWrite()``, but it is badly named, and its use is
+discouraged.
+
+.. contents:: Contents
+   :local:
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: pwmWrite
+
+Example
+-------
+
+Sets the output to the LED proportional to the value read from the
+potentiometer::
+
+    int analogPin = 3;    // potentiometer connected to analog pin 3
+    int val = 0;          // variable to store the read value
+
+    void setup() {
+      pinMode(BOARD_LED_PIN, OUTPUT);   // sets the LED pin as output
+
+      pinMode(analogPin, PWM);   // sets the potentiometer pin as PWM
+                                 // output
+    }
+
+    void loop() {
+      val = analogRead(analogPin);   // read the input pin
+
+      analogWrite(BOARD_LED_PIN, val / 16);  // analogRead values go from 0
+                                             // to 4095, analogWrite values
+                                             // from 0 to 65535
+    }
+
+See Also
+--------
+
+-  :ref:`Maple PWM tutorial <pwm>`
diff --git a/docs/source/lang/api/random.rst b/docs/source/lang/api/random.rst
new file mode 100644
index 0000000..f2a9762
--- /dev/null
+++ b/docs/source/lang/api/random.rst
@@ -0,0 +1,73 @@
+.. highlight:: cpp
+
+.. _lang-random:
+
+random()
+========
+
+The ``random()`` function generates pseudo-random numbers.
+
+.. TODO keep tracking Sphinx/Breathe's ability to reference overloaded
+.. functions so we can use doxygenfunction instead of manually
+.. documenting this.
+
+Library Documentation
+---------------------
+
+.. cpp:function:: random(long max)
+
+   Same as a call to ``random(0, max)``.
+
+.. cpp:function:: random(long min, long max)
+
+   Generate a pseudo-random number with given lower and upper bounds.
+
+   *Parameters*
+
+   - ``min`` - Lower bound on the returned value, inclusive
+   - ``max`` - Upper bound on the returned value, exclusive
+
+   *Returns*: A pseudo-random number in the range [min, max).
+
+Discussion
+----------
+
+If it is important for a sequence of values generated by
+:ref:`random() <lang-random>` to differ, on subsequent executions of a
+sketch, use :ref:`randomSeed() <lang-randomseed>` to initialize the
+random number generator with a fairly random input, such as
+:ref:`analogRead() <lang-analogread>` on an unconnected pin.
+
+Conversely, it can occasionally be useful to use pseudorandom
+sequences that repeat exactly. This can be accomplished by calling
+``randomSeed()`` with a fixed number, before starting the random
+sequence.
+
+Example
+-------
+
+The following sketch initializes the random seed based on an :ref:`ADC
+<adc>` reading of pin 0.  If this pin is unconnected, the Sketch
+should print different values to the :ref:`serial monitor
+<ide-serial-monitor>` each time it is run::
+
+    long randNumber;
+
+    void setup() {
+      pinMode(0, INPUT_ANALOG);
+      randomSeed(analogRead(0));
+    }
+
+    void loop() {
+      randNumber = random(300);
+      SerialUSB.println(randNumber);
+
+      delay(50);
+    }
+
+See Also
+--------
+
+-  :ref:`randomSeed() <lang-randomseed>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/randomseed.rst b/docs/source/lang/api/randomseed.rst
new file mode 100644
index 0000000..d0a15b7
--- /dev/null
+++ b/docs/source/lang/api/randomseed.rst
@@ -0,0 +1,60 @@
+.. highlight:: cpp
+
+.. _lang-randomseed:
+
+randomSeed()
+============
+
+``randomSeed()`` initializes the `pseudorandom number generator
+<http://en.wikipedia.org/wiki/Pseudorandom_number_generator>`_,
+causing it to start at an arbitrary point in its random sequence.
+This sequence, while very long, and random, is always the same.
+
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: randomSeed
+
+Discussion
+----------
+
+If it is important for a sequence of values generated by
+:ref:`random() <lang-random>` to differ, on subsequent executions of a
+sketch, use ``randomSeed()`` to initialize the random number generator
+with a fairly random input, such as :ref:`analogRead()
+<lang-analogread>` on an unconnected pin.
+
+Conversely, it can occasionally be useful to use pseudorandom
+sequences that repeat exactly. This can be accomplished by calling
+``randomSeed()`` with a fixed number, before starting the random
+sequence.
+
+Example
+-------
+
+The following sketch initializes the random seed based on an :ref:`ADC
+<adc>` reading of pin 0.  If this pin is unconnected, the Sketch
+should print different values to the :ref:`serial monitor
+<ide-serial-monitor>` each time it is run::
+
+    long randNumber;
+
+    void setup() {
+      pinMode(0, INPUT_ANALOG);
+      randomSeed(analogRead(0));
+    }
+
+    void loop() {
+      randNumber = random(300);
+      SerialUSB.println(randNumber);
+
+      delay(50);
+    }
+
+See Also
+--------
+
+-  :ref:`random() <lang-random>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/serial.rst b/docs/source/lang/api/serial.rst
new file mode 100644
index 0000000..ca89b31
--- /dev/null
+++ b/docs/source/lang/api/serial.rst
@@ -0,0 +1,226 @@
+.. _lang-serial:
+
+Serial Ports (``Serial1``, ``Serial2``, ``Serial3``)
+====================================================
+
+Used for communication between the Maple board and a computer or other
+devices.
+
+.. contents:: Contents
+   :local:
+
+Introduction
+------------
+
+The Maple has three serial ports (also known as a UARTs or USARTs):
+``Serial1``, ``Serial2``, and ``Serial3``. They communicate using the
+pins summarized in the following table:
+
+.. list-table::
+   :header-rows: 1
+
+   * - Serial port
+     - TX, RX, CK
+     - CTS, RTS (if present)
+
+   * - ``Serial1``
+     - 7, 8, 6
+     -
+
+   * - ``Serial2``
+     - 1, 0, 10
+     - 2, 3
+
+   * - ``Serial3``
+     - 29, 30, 31
+     - 32, 33
+
+Thus, if you use a particular serial port, you cannot also use its
+communication pins for other purposes at the same time.
+
+If you want to communicate with the Maple using the provided USB port,
+use :ref:`SerialUSB <lang-serialusb>` instead.
+
+To use them to communicate with an external TTL serial device, connect
+the TX pin to your device's RX pin, the RX to your device's TX pin,
+and the ground of your Maple to your device's ground.
+
+.. warning:: Don't connect these pins directly to an RS232 serial
+   port; they operate at +/- 12V and can damage your board.
+
+
+Library Documentation
+---------------------
+
+All of the ``Serial[1,2,3]`` objects are instances of the
+``HardwareSerial`` class, which is documented in this section.  (This
+means that you can use any of these functions on any of ``Serial1``,
+``Serial2``, and ``Serial3``).
+
+.. cpp:class:: HardwareSerial
+
+   Serial port class.  Predefined instances are ``Serial1``,
+   ``Serial2``, and ``Serial3``.
+
+.. cpp:function:: HardwareSerial::begin(unsigned int baud)
+
+   Set up a ``HardwareSerial`` object for communications.  This method
+   must be called before attempting to use the ``HardwareSerial``
+   object (typically, you call this in your :ref:`setup()
+   <lang-setup>` function).
+
+.. cpp:function:: HardwareSerial::end()
+
+   Disables the USART associated with this object, allowing any
+   associated communication pins to be used for other purposes.
+
+.. cpp:function:: unsigned int HardwareSerial::available()
+
+   Returns the number of bytes available for reading.
+
+.. cpp:function:: unsigned char HardwareSerial::read()
+
+   Returns the next available, unread character.  If there are no
+   available characters (you can check this with :cpp:func:`available
+   <HardwareSerial::available>`), the call will block until one
+   becomes available.
+
+.. cpp:function:: HardwareSerial::flush()
+
+   Removes the contents of the Serial's associated USART RX FIFO.
+   That is, clears any buffered characters, so that the next character
+   read is guaranteed to be new.
+
+.. cpp:function:: HardwareSerial::print(unsigned char b)
+
+   Print the given byte over the USART.
+
+.. cpp:function:: HardwareSerial::print(char c)
+
+   Print the given character over the USART.  7-bit clean characters
+   are typically interpreted as ASCII text.
+
+.. cpp:function:: HardwareSerial::print(const char *str)
+
+   Print the given null-terminated string over the USART.
+
+.. cpp:function:: HardwareSerial::print(int n)
+
+   Print the argument's digits over the USART, in decimal format.
+   Negative values will be prefixed with a ``'-'`` character.
+
+.. cpp:function:: HardwareSerial::print(unsigned int n)
+
+   Print the argument's digits over the USART, in decimal format.
+
+.. cpp:function:: HardwareSerial::print(long n)
+
+   Print the argument's digits over the USART, in decimal format.
+   Negative values will be prefixed with a ``'-'`` character.
+
+.. cpp:function:: HardwareSerial::print(unsigned long n)
+
+   Print the argument's digits over the USART, in decimal format.
+
+.. cpp:function:: HardwareSerial::print(long n, int base)
+
+   Print the digits of ``n`` over the USART, in base ``base`` (which
+   may be between 2 and 16).  The ``base`` value 2 corresponds to
+   binary, 8 to octal, 10 to decimal, and 16 to hexadecimal.  Negative
+   values will be prefixed with a ``'-'`` character.
+
+.. cpp:function:: HardwareSerial::print(double n)
+
+   Print ``n``, accurate to 2 digits after the decimal point.
+
+.. _lang-serial-println:
+
+.. cpp:function:: HardwareSerial::println(char c)
+
+   Like ``print(c)``, followed by ``"\r\n"``.
+
+.. cpp:function:: HardwareSerial::println(const char *c)
+
+   Like ``print(c)``, followed by ``"\r\n"``.
+
+.. cpp:function:: HardwareSerial::println(unsigned char b)
+
+   Like ``print(b)``, followed by ``"\r\n"``.
+
+.. cpp:function:: HardwareSerial::println(int n)
+
+   Like ``print(n)``, followed by ``"\r\n"``.
+
+.. cpp:function:: HardwareSerial::println(unsigned int n)
+
+   Like ``print(n)``, followed by ``"\r\n"``.
+
+.. cpp:function:: HardwareSerial::println(long n)
+
+   Like ``print(n)``, followed by ``"\r\n"``.
+
+.. cpp:function:: HardwareSerial::println(unsigned long n)
+
+   Like ``print(n)``, followed by ``"\r\n"``.
+
+.. cpp:function:: HardwareSerial::println(long n, int base)
+
+   Like ``print(n, b)``, followed by ``"\r\n"``.
+
+.. cpp:function:: HardwareSerial::println(double n)
+
+   Like ``print(n)``, followed by ``"\r\n"``.
+
+.. cpp:function:: HardwareSerial::println()
+
+   Prints ``"\r\n"`` over the USART.
+
+.. cpp:function:: HardwareSerial::write(unsigned char ch)
+
+   Sends one character over the USART.  This function is currently
+   blocking, although nonblocking writes are a planned future
+   extension.
+
+   This is a low-level function.  One of the ``print()`` or
+   ``println()`` functions is likely to be more useful when printing
+   multiple characters, when formatting numbers for printing, etc.
+
+.. cpp:function:: HardwareSerial::write(const char* str)
+
+   Send the given null-terminated character string over the USART.
+
+   This is a low-level function.  One of the ``print()`` or
+   ``println()`` functions is likely to be more useful when printing
+   multiple characters, when formatting numbers for printing, etc.
+
+.. cpp:function:: HardwareSerial::write(void *buf, unsigned int size)
+
+   Writes the first ``size`` bytes of ``buf`` over the USART.  Each
+   byte is transmitted as an individual character.
+
+   This is a low-level function.  One of the ``print()`` or
+   ``println()`` functions is likely to be more useful when printing
+   multiple characters, when formatting numbers for printing, etc.
+
+Arduino Compatibility Note
+--------------------------
+
+Unlike the Arduino, none of the Maple's serial ports is connected to
+the USB port on the Maple board (for that, use :ref:`SerialUSB
+<lang-serialusb>`).  Thus, to use these pins to communicate with your
+personal computer, you will need an additional USB-to-serial adaptor.
+
+.. TODO LATER port these examples over
+
+.. Examples
+.. --------
+
+.. -  `ASCII Table <http://arduino.cc/en/Tutorial/ASCIITable>`_
+.. -  `Dimmer <http://arduino.cc/en/Tutorial/Dimmer>`_
+.. -  `Graph <http://arduino.cc/en/Tutorial/Graph>`_
+.. -  `Physical Pixel <http://arduino.cc/en/Tutorial/PhysicalPixel>`_
+.. -  `Virtual Color Mixer <http://arduino.cc/en/Tutorial/VirtualColorMixer>`_
+.. -  `Serial Call Response <http://arduino.cc/en/Tutorial/SerialCallResponse>`_
+.. -  `Serial Call Response ASCII <http://arduino.cc/en/Tutorial/SerialCallResponseASCII>`_
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/serialusb.rst b/docs/source/lang/api/serialusb.rst
new file mode 100644
index 0000000..3bb8c00
--- /dev/null
+++ b/docs/source/lang/api/serialusb.rst
@@ -0,0 +1,243 @@
+.. highlight:: cpp
+
+.. _lang-serialusb:
+
+``SerialUSB``
+=============
+
+Used for communication between the Maple board and a computer.
+
+.. contents:: Contents
+   :local:
+
+Introduction
+------------
+
+In addition to three :ref:`serial ports <lang-serial>`, the Maple's
+STM32 microprocessor includes a dedicated USB peripheral.  This
+peripheral is used to emulate a regular serial port for use as a
+terminal (text read/write).  The emulated terminal is relatively slow
+and inefficient; it is best for transferring data at regular serial
+speeds (kilobaud).
+
+Library access to the emulated serial port is provided through the
+``SerialUSB`` object.  You can mostly use ``SerialUSB`` as a drop-in
+replacement for ``Serial1``, ``Serial2``, and ``Serial3``.
+
+.. warning:: The ``SerialUSB`` functionality includes a 50 millisecond
+   timeout for writes, and does not try to detect if the USB host is
+   "really" connected, or just enumerated and initialized.
+
+   This means that if you have a number of calls to one of the
+   ``SerialUSB`` ``write()`` or ``print()`` functions in your code,
+   and you are not monitoring the emulated on a computer, your program
+   will run much, much slower than if it is being monitored or totally
+   disconnected (run off of a battery).
+
+   You can avoid this behavior by :ref:`deciphering the port status
+   using the DTR and RTS line status <lang-serialusb-safe-print>`; the
+   behavior of these control lines is platform dependent and we no
+   longer interpret them by default.
+
+Library Documentation
+---------------------
+
+The ``SerialUSB`` object is an instance of the ``USBSerial`` class,
+which is documented in this section.  This means that you can use any
+of these functions by writing
+``SerialUSB.functionName(arguments...)``.  For example, to print the
+message "hello, world!", you can write ``USBSerial.println("hello,
+world!")``.
+
+.. cpp:class:: USBSerial
+
+   Emulated serial-over-USB class.  ``SerialUSB`` is the predefined
+   (singleton) instance.
+
+.. _lang-serialusb-begin:
+
+.. cpp:function:: USBSerial::begin()
+
+   Set up the USB peripheral for emulated serial communication.  The
+   peripheral is configured this way by default; calling this function
+   should only be necessary if you have disabled the peripheral using
+   ``SerialUSB.end()``.
+
+.. _lang-serialusb-end:
+
+.. cpp:function:: USBSerial::end()
+
+   Disables the USB peripheral.  Note that using this function will
+   terminate all USB communications between the Maple and the USB
+   host; in particular, it implies that you won't be able to upload
+   any new programs without resetting the board or using
+   :ref:`perpetual bootloader mode
+   <troubleshooting-perpetual-bootloader>`.
+
+.. cpp:function:: unsigned int USBSerial::available()
+
+   Returns the number of bytes available for reading.
+
+.. _lang-serialusb-read:
+
+.. cpp:function:: unsigned char USBSerial::read()
+
+   Returns the next available, unread character.  If there are no
+   available characters (you can check this with :cpp:func:`available
+   <USBSerial::available>`), the call will block until one
+   becomes available.
+
+.. cpp:function:: USBSerial::print(unsigned char b)
+
+   Print the given byte over the USB connection.
+
+.. cpp:function:: USBSerial::print(char c)
+
+   Print the given character over the USB connection.  7-bit clean characters
+   are typically interpreted as ASCII text.
+
+.. cpp:function:: USBSerial::print(const char *str)
+
+   Print the given null-terminated string over the USB connection.
+
+.. cpp:function:: USBSerial::print(int n)
+
+   Print the argument's digits over the USB connection, in decimal format.
+   Negative values will be prefixed with a ``'-'`` character.
+
+.. cpp:function:: USBSerial::print(unsigned int n)
+
+   Print the argument's digits over the USB connection, in decimal format.
+
+.. cpp:function:: USBSerial::print(long n)
+
+   Print the argument's digits over the USB connection, in decimal
+   format.  Negative values will be prefixed with a ``'-'`` character.
+
+.. cpp:function:: USBSerial::print(unsigned long n)
+
+   Print the argument's digits over the USB connection, in decimal
+   format.
+
+.. cpp:function:: USBSerial::print(long n, int base)
+
+   Print the digits of ``n`` over the USB connection, in base ``base``
+   (which may be between 2 and 16).  The ``base`` value 2 corresponds
+   to binary, 8 to octal, 10 to decimal, and 16 to hexadecimal.
+   Negative values will be prefixed with a ``'-'`` character.
+
+.. cpp:function:: USBSerial::print(double n)
+
+   Print ``n``, accurate to 2 digits after the decimal point.
+
+.. _lang-serialusb-println:
+
+.. cpp:function:: USBSerial::println(char c)
+
+   Like ``print(c)``, followed by ``"\r\n"``.
+
+.. cpp:function:: USBSerial::println(const char *c)
+
+   Like ``print(c)``, followed by ``"\r\n"``.
+
+.. cpp:function:: USBSerial::println(unsigned char b)
+
+   Like ``print(b)``, followed by ``"\r\n"``.
+
+.. cpp:function:: USBSerial::println(int n)
+
+   Like ``print(n)``, followed by ``"\r\n"``.
+
+.. cpp:function:: USBSerial::println(unsigned int n)
+
+   Like ``print(n)``, followed by ``"\r\n"``.
+
+.. cpp:function:: USBSerial::println(long n)
+
+   Like ``print(n)``, followed by ``"\r\n"``.
+
+.. cpp:function:: USBSerial::println(unsigned long n)
+
+   Like ``print(n)``, followed by ``"\r\n"``.
+
+.. cpp:function:: USBSerial::println(long n, int base)
+
+   Like ``print(n, b)``, followed by ``"\r\n"``.
+
+.. cpp:function:: USBSerial::println(double n)
+
+   Like ``print(n)``, followed by ``"\r\n"``.
+
+.. cpp:function:: USBSerial::println()
+
+   Prints ``"\r\n"`` over the USB connection.
+
+.. cpp:function:: USBSerial::write(unsigned char ch)
+
+   Sends one character over the USB connection.  This function is
+   currently blocking, although nonblocking writes are a planned
+   future extension.
+
+   This is a low-level function.  One of the ``print()`` or
+   ``println()`` functions is likely to be more useful when printing
+   multiple characters, when formatting numbers for printing, etc.
+
+.. cpp:function:: USBSerial::write(const char* str)
+
+   Send the given null-terminated character string over the USB
+   connection.
+
+   This is a low-level function.  One of the ``print()`` or
+   ``println()`` functions is likely to be more useful when printing
+   multiple characters, when formatting numbers for printing, etc.
+
+.. cpp:function:: USBSerial::write(void *buf, unsigned int size)
+
+   Writes the first ``size`` bytes of ``buf`` over the USB connection.
+   Each byte is transmitted as an individual character.
+
+   This is a low-level function.  One of the ``print()`` or
+   ``println()`` functions is likely to be more useful when printing
+   multiple characters, when formatting numbers for printing, etc.
+
+Examples
+--------
+
+.. _lang-serialusb-safe-print:
+
+**Safe print**: This function should run smoothly and not block; the
+LED should blink at roughly the same speed whether being monitored,
+running from battery, or connected but not monitored. You may need to
+experiment with the DTR/RTS logic for your platform and device
+configuration. ::
+
+    #define LED_PIN 13
+
+    void setup() {
+        /* Set up the LED to blink  */
+        pinMode(LED_PIN, OUTPUT);
+    }
+
+    void loop() {
+        // LED will stay off if we are disconnected;
+        // will blink quickly if USB is unplugged (battery etc)
+        if(SerialUSB.isConnected()) {
+            digitalWrite(LED_PIN, 1);
+        }
+        delay(100);
+
+        // If this logic fails to detect if bytes are going to
+        // be read by the USB host, then the println() will fully
+        // many times, causing a very slow LED blink.
+        // If the characters are printed and read, the blink will
+        // only slow a small amount when "really" connected, and fast
+        // when the virtual port is only configured.
+        if(SerialUSB.isConnected() && (SerialUSB.getDTR() || SerialUSB.getRTS())) {
+            for(int i=0; i<10; i++) {
+               SerialUSB.println(123456,BIN);
+            }
+        }
+        digitalWrite(LED_PIN, 0);
+        delay(100);
+    }
+
diff --git a/docs/source/lang/api/setup.rst b/docs/source/lang/api/setup.rst
new file mode 100644
index 0000000..837ddd6
--- /dev/null
+++ b/docs/source/lang/api/setup.rst
@@ -0,0 +1,29 @@
+.. highlight:: cpp
+
+.. _lang-setup:
+
+setup()
+=======
+
+The ``setup()`` function is called when a sketch starts. Use it to
+initialize :ref:`variables <lang-variables>`, :ref:`pin modes
+<lang-pinmode>`, start using :ref:`libraries <libraries>`, etc. The
+``setup()`` function will only run once, after each power-up or reset
+of the Maple board.
+
+Example
+-------
+
+::
+
+    int buttonPin = 38;
+
+    void setup() {
+      pinMode(buttonPin, INPUT);
+    }
+
+    void loop() {
+      // ...
+    }
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/sin.rst b/docs/source/lang/api/sin.rst
new file mode 100644
index 0000000..398b8f3
--- /dev/null
+++ b/docs/source/lang/api/sin.rst
@@ -0,0 +1,32 @@
+.. _lang-sin:
+
+sin()
+=====
+
+Calculates the `sine <http://en.wikipedia.org/wiki/Sine>`_ of an
+angle.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: sin
+
+Arduino Compatibility
+---------------------
+
+The Maple version of ``sin()`` is compatible with Arduino.
+
+Note that the Maple implementation comes from `newlib
+<http://sourceware.org/newlib/>`_\ , while Arduino's is that of
+`avr-libc <http://avr-libc.nongnu.org/>`_\ .
+
+See Also
+--------
+
+-  :ref:`cos <lang-cos>`
+-  :ref:`tan <lang-tan>`
+-  :ref:`float <lang-float>`
+-  :ref:`double <lang-double>`
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/sq.rst b/docs/source/lang/api/sq.rst
new file mode 100644
index 0000000..bd32648
--- /dev/null
+++ b/docs/source/lang/api/sq.rst
@@ -0,0 +1,46 @@
+.. highlight:: cpp
+
+.. _lang-sq:
+
+sq()
+====
+
+(Macro) computes the square of a number.
+
+Syntax
+------
+
+::
+
+    sq(a)
+
+Parameters
+----------
+
+**a**: the number.
+
+Returns
+-------
+
+**a** squared (**a** × **a**).
+
+Warning
+-------
+
+Because of the way ``sq()`` is implemented, avoid using other
+functions or causing side effects inside the parentheses, as it may
+lead to incorrect results::
+
+    b = sq(a++);   // avoid this - yields incorrect results
+
+    b = sq(a);     // use this instead -
+    a++;           // keep other operations outside sq()
+
+
+Arduino Compatibility
+---------------------
+
+Maple's implementation of ``sq()`` is compatible with Arduino.
+
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/tan.rst b/docs/source/lang/api/tan.rst
new file mode 100644
index 0000000..4bbe0db
--- /dev/null
+++ b/docs/source/lang/api/tan.rst
@@ -0,0 +1,31 @@
+.. _lang-tan:
+
+tan()
+=====
+
+Calculates the tangent of an angle.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: tan
+
+Arduino Compatibility
+---------------------
+
+The Maple version of ``tan()`` is compatible with Arduino.
+
+Note that the Maple implementation comes from `newlib
+<http://sourceware.org/newlib/>`_\ , while Arduino's is that of
+`avr-libc <http://avr-libc.nongnu.org/>`_\ .
+
+See Also
+--------
+
+
+-  :ref:`sin <lang-sin>`
+-  :ref:`cos <lang-cos>`
+-  :ref:`float <lang-float>`
+-  :ref:`double <lang-double>`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/toggleled.rst b/docs/source/lang/api/toggleled.rst
new file mode 100644
index 0000000..0cc20c2
--- /dev/null
+++ b/docs/source/lang/api/toggleled.rst
@@ -0,0 +1,17 @@
+.. _lang-toggleled:
+
+toggleLED()
+===========
+
+Switches the LED from off to on, or on to off.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: toggleLED
+
+See Also
+--------
+
+- :ref:`BOARD_LED_PIN <lang-constants-led>`
+- :ref:`togglePin() <lang-togglepin>`
diff --git a/docs/source/lang/api/togglepin.rst b/docs/source/lang/api/togglepin.rst
new file mode 100644
index 0000000..290718d
--- /dev/null
+++ b/docs/source/lang/api/togglepin.rst
@@ -0,0 +1,17 @@
+.. _lang-togglepin:
+
+togglePin()
+===========
+
+Switches a digital output pin from :ref:`HIGH <lang-constants-high>`
+to :ref:`LOW <lang-constants-low>`, or from LOW to HIGH.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: togglePin
+
+See Also
+--------
+
+- :ref:`toggleLED() <lang-toggleled>`
diff --git a/docs/source/lang/api/volatile.rst b/docs/source/lang/api/volatile.rst
new file mode 100644
index 0000000..276bb6a
--- /dev/null
+++ b/docs/source/lang/api/volatile.rst
@@ -0,0 +1,65 @@
+.. highlight:: cpp
+
+.. _lang-volatile:
+
+``volatile``
+============
+
+The ``volatile`` keyword known is a variable *qualifier*.  It is
+usually used before the datatype of a variable, to modify the way in
+which the compiler treats the variable.
+
+Declaring a variable ``volatile`` is a directive to the compiler. The
+compiler is software which translates your C++ code into the machine
+code, which are the real instructions for the STM32 chip in the
+Maple. (The particular compiler we provide for use with the Maple is a
+version of :ref:`GCC <arm-gcc>`).
+
+Specifically, it directs the compiler to read the variable's value
+fresh every time it is used, rather than "backing up" the value and
+reading from its backup copy. (Compilers often "back up" a variable's
+value in RAM into a storage location called a *register*; this is done
+for efficiency).
+
+A variable should be declared ``volatile`` whenever its value can be
+changed by something beyond the control of the code section in which
+it appears, such as an :ref:`external interrupt
+<external-interrupts>`. On the Maple, the only place that this is
+likely to occur is in sections of code associated with interrupts.
+
+Example
+-------
+
+::
+
+    // toggles LED when interrupt pin changes state
+
+    int pin = 13;
+    volatile int state = LOW;
+
+    void setup() {
+      pinMode(pin, OUTPUT);
+      attachInterrupt(0, blink, CHANGE);
+    }
+
+    void loop() {
+      digitalWrite(pin, state);
+    }
+
+    void blink() {
+      if (state == HIGH) {
+        state = LOW;
+      } else {
+        // state must be HIGH
+        state = HIGH;
+      }
+    }
+
+See also
+--------
+
+- :ref:`External Interrupts <external-interrupts>`
+- :ref:`lang-attachinterrupt`
+- :ref:`lang-detachinterrupt`
+
+.. include:: cc-attribution.txt
diff --git a/docs/source/lang/api/waitforbuttonpress.rst b/docs/source/lang/api/waitforbuttonpress.rst
new file mode 100644
index 0000000..34c5066
--- /dev/null
+++ b/docs/source/lang/api/waitforbuttonpress.rst
@@ -0,0 +1,17 @@
+.. _lang-waitforbuttonpress:
+
+waitForButtonPress()
+====================
+
+Wait for the board's built-in button (labeled BUT on the silkscreen)
+to be pressed, possibly with timeout.
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: waitForButtonPress
+
+See Also
+--------
+
+- :ref:`lang-isbuttonpressed`