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+.. highlight:: cpp
+
+.. _libs-servo:
+
+=======
+ Servo
+=======
+
+This documents the Servo library for controlling RC servomotors.  It
+is implemented as a thin layer over the built-in :ref:`timer
+peripherals <timers>`.
+
+You can use this library in the :ref:`IDE <ide>` by choosing the Servo
+item under the Sketch > Import Library... menu.
+
+If you are using the :ref:`Unix toolchain <unix-toolchain>`, the
+library is located in ``$LIB_MAPLE_HOME/libraries/Servo/``.
+
+Servo Class Reference
+---------------------
+
+You can construct a Servo object by including the declaration ::
+
+     Servo servo;
+
+in your sketch.  This will create a Servo object called ``servo``.
+You can then use any of its methods; for instance, to control a
+servomotor attached to pin 9, you could write ::
+
+     servo.attach(9);
+
+.. cpp:class:: Servo
+
+   Class for controlling RC servomotors via :ref:`timers <timers>`.
+
+.. _libs-servo-attach:
+
+.. cpp:function:: bool Servo::attach(uint8 pin, uint16 min, uint16 max)
+
+   Attach this Servo object to the given ``pin``.  The pin must be
+   capable of PWM.  You can check this by seeing if "PWM" is written
+   next to its number on the Maple silkscreen, or by consulting the
+   :ref:`pwmWrite() <lang-pwmwrite>` documentation.
+
+   Sets this pin's :ref:`mode <lang-pinmode>` to :ref:`PWM
+   <lang-pinmode-wiringpinmode>`, and returns true if successful.
+   Does nothing and returns false if the pin doesn't support PWM.
+
+   Parameter ``min`` is the pulse width corresponding to 0 degrees;
+   ``max`` is the pulse width corresponding to 180 degrees (both are
+   in microseconds).
+
+.. cpp:function:: bool Servo::attach(uint8 pin)
+
+   Equivalent to :ref:`attach(pin, 544, 2400) <libs-servo-attach>`.
+
+.. _libs-servo-attached:
+
+.. cpp:function:: int Servo::attached() const
+
+   If currently attached (via :ref:`attach() <libs-servo-attach>`) to
+   a pin, returns that pin's number.  Returns ``NOT_ATTACHED``
+   otherwise.
+
+.. cpp:function:: bool Servo::detach()
+
+   If this Servo object is currently attached to pin, stops driving
+   the servo by setting a zero pulse width (this is accomplished by
+   setting the associated :ref:`channel mode
+   <lang-hardwaretimer-setchannelmode>` to ``TIMER_DISABLED``).
+
+   Subsequently, calling :ref:`attached() <libs-servo-attached>` will
+   return ``NOT_ATTACHED``.
+
+.. cpp:function:: void Servo::write(unsigned int value)
+
+   If ``value`` is less than ``SERVO_MAX_WRITE_ANGLE`` (which, for
+   Arduino compatibility, is 200), it's interpreted as an angle in
+   degrees.  Otherwise, it's treated as a pulse width in microseconds.
+
+   Drives the servo to target the given angle, based on a linear
+   interpolation of the ``min`` and ``max`` pulse widths determined
+   when :ref:`attach() <libs-servo-attach>` was called.
+
+   Be aware that some (especially lower-cost) servos have fairly
+   non-linear maps between pulse width and target angle.  Make sure to
+   test your motor before relying on this method.
+
+.. cpp:function:: void Servo::writeMicroseconds(uint16 pulseWidth)
+
+   Drives the servo using a ``pulseWidth``-microsecond pulse.
+
+   If ``pulseWidth`` is outside of the [``min``, ``max``\ ] pulse
+   width range set during :ref:`attach() <libs-servo-attach>`, it will
+   be clamped to lie in this range.
+
+.. cpp:function:: int Servo::read() const
+
+   Returns the servo's target angle, in degrees.  This will be clamped
+   to lie between 0 (when the pulse width is at most ``min``) and 180
+   (when the pulse width is at least ``max``).
+
+.. cpp:function:: uint16 Servo::readMicroseconds() const
+
+   Returns the pulse width of the wave currently driving the servo, in
+   microseconds.  This will be clamped to lie in the [``min``,
+   ``max``\ ] pulse width range set during :ref:`attach()
+   <libs-servo-attach>`.