From 210f3d2b1555bae87c9de27ea145e16d3bddb0f8 Mon Sep 17 00:00:00 2001 From: Marti Bolivar Date: Fri, 3 Dec 2010 20:18:00 -0500 Subject: cleaning up previous commits. note that addition of new files under docs/source/lang/api and docs/source/lang/cpp which were just copies of files in docs/source/lang/ imply that change history is lost to git. --- source/lang/digitalwrite.rst | 68 -------------------------------------------- 1 file changed, 68 deletions(-) delete mode 100644 source/lang/digitalwrite.rst (limited to 'source/lang/digitalwrite.rst') diff --git a/source/lang/digitalwrite.rst b/source/lang/digitalwrite.rst deleted file mode 100644 index 6124d5f..0000000 --- a/source/lang/digitalwrite.rst +++ /dev/null @@ -1,68 +0,0 @@ -.. highlight:: cpp - -.. _lang-digitalwrite: - -digitalWrite() -============== - -Write a :ref:`HIGH ` or a :ref:`LOW -` value to a pin configured as :ref:`OUTPUT -`. - -Library Documentation ---------------------- - -.. doxygenfunction:: digitalWrite - -Discussion ----------- - -If the pin has been configured as an ``OUTPUT`` with :ref:`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() ` 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 ` -- :ref:`digitalRead ` - -.. include:: cc-attribution.txt -- cgit v1.2.3