diff options
Diffstat (limited to 'docs/source/gpio.rst')
| -rw-r--r-- | docs/source/gpio.rst | 107 |
1 files changed, 0 insertions, 107 deletions
diff --git a/docs/source/gpio.rst b/docs/source/gpio.rst deleted file mode 100644 index af1de20..0000000 --- a/docs/source/gpio.rst +++ /dev/null @@ -1,107 +0,0 @@ -.. _gpio: - -GPIO -==== - -Each LeafLabs board comes with ready-to-use General Purpose -Input/Output (GPIO) pins, which are numbered starting from zero. -These numbers are listed on your board's silkscreen, next to where the -pin is broken out to a header. Many pins may additionally be used for -special features or interfacing with other hardware. - -.. contents:: Contents - :local: - -.. _gpio-modes: - -GPIO Modes ----------- - -Each GPIO pin can be configured using :ref:`lang-pinmode` to behave in -a number of ways: as a digital output pin, as an analog input pin, -etc. - -A :ref:`WiringPinMode <lang-pinmode-wiringpinmode>` value specifies -the complete set of possible configurations; not every pin can have -all of these modes. For example, on the Maple, pin 15 may have mode -``INPUT_ANALOG``, but not ``PWM``. See your board's :ref:`pin maps -<gpio-pin-maps>` and its silkscreen for more information on what -functionality is available on each pin. - -Function Reference ------------------- - -- :ref:`lang-pinmode` - -- :ref:`lang-digitalread` - -- :ref:`lang-digitalwrite` - -- :ref:`lang-analogread` - -- :ref:`lang-pwmwrite` (Maple's equivalent to ``analogWrite()``; see - :ref:`lang-analogwrite` for differences from the Arduino version). - -.. _gpio-ports: - -GPIO Ports ----------- - -Normally, you'll interact with pins using just their number (or a -constant like :ref:`BOARD_LED_PIN <lang-board-values-led>` which -stands for a number). However, behind the scenes, the STM32 -microcontroller on your board separates the pins into groups called -*GPIO ports*. Each GPIO port is given a letter, so for example, -there's GPIO port A, port B, and so on\ [#fnumports]_. The pins on a -GPIO port are given *bit numbers*, which go from 0 to 15. In ST's -documentation, a pin is given by the letter "P", followed by its port -letter and bit number. For instance, "PA4" is GPIO port A, bit 4. - -.. _gpio-pin-maps: - -Pin Maps --------- - -Part of :ref:`Maple IDE's <ide>` job is to convert normal pin numbers -into the corresponding GPIO port and bit when you call functions like -:ref:`lang-pinmode`. It does this using a *pin map*, which lists the -GPIO port and bit for each pin number. The GPIO documentation for -your board includes its pin map, which also lists the other -peripherals by pin number: - -.. TODO [0.0.12] Native link - -* :ref:`Maple <maple-gpios>` -* :ref:`Maple RET6 Edition <maple-ret6-gpios>` -* :ref:`Maple Mini <maple-mini-gpios>` - -.. * :ref:`Maple Native <maple-native-gpios>` - -.. _gpio-5v-tolerant: - -The current and voltage limitations were determined using the STM32 -datasheets. In particular, only some GPIO pins are **5V tolerant**, -which means that applying 5 volts to a pin and reading it as input or -allowing it to drain to ground will not damage that pin. Connecting a -voltage higher than 3.3V to a non-5V tolerant pin may damage your -board. - -.. _gpio-recommended-reading: - -Recommended Reading -------------------- - -* ST Documentation for the STM32F103 series of microcontrollers: - - * `Reference Manual RM0008 - <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/REFERENCE_MANUAL/CD00171190.pdf>`_ - (PDF); general, definitive resource for STM32F1 line. - * `Programming Manual PM0056 - <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/PROGRAMMING_MANUAL/CD00228163.pdf>`_ - (PDF); assembly language and register reference. - -.. rubric:: Footnotes - -.. [#fnumports] The total number of GPIO ports depends on what board - you have. For example, Maple Mini has three: ports A, B, and C. - Maple Native has seven: ports A through G. |