Merge branch 'master' into debug-serialusb.

Chose debug-serialusb version in cases of conflict.

Conflicts:
	libmaple/usb/usb_callbacks.c

1 files changed, 56 insertions, 0 deletions

diff --git a/docs/source/lang/api/pwmwrite.rst b/docs/source/lang/api/pwmwrite.rst
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+.. 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>`