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diff --git a/docs/source/arduino/analogwrite.rst b/docs/source/arduino/analogwrite.rst deleted file mode 100644 index 64ecd5b..0000000 --- a/docs/source/arduino/analogwrite.rst +++ /dev/null @@ -1,116 +0,0 @@ -.. _arduino-analogwrite: - -analogWrite() -============= - -TODO - -In libmaple, analogWrite is just a convenience alias for -:ref:`pwmWrite`. This is because PWM is not true analog output (i.e., -is not the output of a DAC), so the name was badly-chosen; however, -for the sake of compatibility, the alias was provided. - -.. doxygenfunction:: pwmWrite - -Description ------------ - -Writes an analog value -(`PWM wave <http://arduino.cc/en/Tutorial/PWM>`_) to a pin. Can be -used to light a LED at varying brightnesses or drive a motor at -various speeds. After a call to **analogWrite()**, the pin will -generate a steady square wave of the specified duty cycle until the -next call to **analogWrite()** (or a call to **digitalRead()** or -**digitalWrite()** on the same pin). The frequency of the PWM -signal is approximately 490 Hz. - - - -On most Arduino boards (those with the ATmega168 or ATmega328), -this function works on pins 3, 5, 6, 9, 10, and 11. On the Arduino -Mega, it works on pins 2 through 13. Older Arduino boards with an -ATmega8 only support analogWrite() on pins 9, 10, and 11. You do -not need to call pinMode() to set the pin as an output before -calling analogWrite(). - - - -The *analogWrite* function has nothing whatsoever to do with the -analog pins or the *analogRead* function. - - - -Syntax ------- - -analogWrite(pin, value) - - - -Parameters ----------- - -pin: the pin to write to. - - - -value: the duty cycle: between 0 (always off) and 255 (always on). - - - -Returns -------- - -nothing - - - -Notes and Known Issues ----------------------- - -The PWM outputs generated on pins 5 and 6 will have -higher-than-expected duty cycles. This is because of interactions -with the millis() and delay() functions, which share the same -internal timer used to generate those PWM outputs. This will be -noticed mostly on low duty-cycle settings (e.g 0 - 10) and may -result in a value of 0 not fully turning off the output on pins 5 -and 6. - - - -Example -------- - -Sets the output to the LED proportional to the value read from the -potentiometer. - - - -:: - - - int ledPin = 9; // LED connected to digital pin 9 - int analogPin = 3; // potentiometer connected to analog pin 3 - int val = 0; // variable to store the read value - - void setup() - { - pinMode(ledPin, OUTPUT); // sets the pin as output - } - - void loop() - { - val = analogRead(analogPin); // read the input pin - analogWrite(ledPin, val / 4); // analogRead values go from 0 to 1023, analogWrite values from 0 to 255 - } - - - -See also --------- - - -- `analogRead <http://arduino.cc/en/Reference/AnalogRead>`_\ () -- `Tutorial: PWM <http://arduino.cc/en/Tutorial/PWM>`_ - - |