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authorMarti Bolivar <mbolivar@mit.edu>2010-11-28 11:23:33 -0500
committerMarti Bolivar <mbolivar@mit.edu>2010-11-28 11:23:33 -0500
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reorganized all the arduino/ docs into a lang/ subdirectory since
they're properly CC attributed now.
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+.. 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