0.0.10 Documentation checkpoint.

The vast majority of the Maple-specific values have been pulled out of
the higher-level overview pages and replaced with refs into documents
under /docs/source/hardware/.

Much of the work that's left to be done in this regard is labeled with
versioned TODO and FIXME comments.

Suggestions from StephenFromNYC and gbulmer were incorporated from
this forum thread:

      http://forums.leaflabs.com/topic.php?id=703

1 files changed, 43 insertions, 71 deletions

diff --git a/source/gpio.rst b/source/gpio.rst
index 0f9f4df..74be3d4 100644
--- a/source/gpio.rst
+++ b/source/gpio.rst
@@ -3,86 +3,54 @@
 GPIO
 ====
 
-.. FIXME [Maple-specific values]
+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 peripheral functions.
 
-The Maple features 38 ready-to-use general purpose input/output (GPIO)
-pins for digital input/output, numbered D0 through D37.  These numbers
-correspond to the numeric values next to each header on the Maple
-silkscreen.
+.. contents:: Contents
+   :local:
 
-Many of these pins may additionally be used for special features or
-peripheral functions.  This page documents those capabilities, by pin.
+.. _gpio-pin-maps:
 
-The current and voltage limitations have been copied over from the
-STM32 datasheet (see the :ref:`Recommended Reading
-<gpio-recommended-reading>` for a link).  In particular, a number of
-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), while some are not.
+Pin Maps
+--------
 
-.. contents:: Contents
-   :local:
+The hardware documentation for your board lists each pin's
+capabilities, by pin number:
+
+.. TODO [0.1.0] Uncomment Mini and Native GPIO links
+
+* :ref:`Maple <maple-gpios>`
+* :ref:`Maple RET6 Edition <maple-ret6-gpios>`
 
-.. _pin-mapping-mega-table:
-
-Pin Mapping Mega Table
-----------------------
-
-This table shows the available functionality on every GPIO pin, by
-peripheral type. The "STM32" column refers to the port and number that
-the header is connected to on the microcontroller.  The "5V?" column
-documents whether or not the pin is 5 volt tolerant (see above).
-
-.. TODO silkscreen pictures which let you know what each abbreviation
-.. means, with links to the relevant documentation.
-
-.. csv-table::
-   :header: "Pin", "STM32", ":ref:`ADC <adc>`", ":ref:`Timer <timers>`", ":ref:`I2C <i2c>`", ":ref:`UART <usart>`", ":ref:`SPI <spi>`", "5v?"
-
-   "D0",  "PA3",  "ADC3",  "TIM2_CH4",     "-",          "USART2_RX",  "-",         "No"
-   "D1",  "PA2",  "ADC2",  "TIM2_CH3",     "-",          "USART2_TX",  "-",         "No"
-   "D2",  "PA0",  "ADC0",  "TIM2_CH1_ETR", "-",          "USART2_CTS", "-",         "No"
-   "D3",  "PA1",  "ADC1",  "TIM2_CH2",     "-",          "USART2_RTS", "-",         "No"
-   "D4",  "PB5",  "-",     "-",            "ISC1_SMBA",  "-",          "-",         "No"
-   "D5",  "PB6",  "-",     "TIM4_CH1",     "I2C1_SCL",   "-",          "-",         "Yes"
-   "D6",  "PA8",  "-",     "TIM1_CH1",     "-",          "USART1_CK",  "-",         "Yes"
-   "D7",  "PA9",  "-",     "TIM1_CH2",     "-",          "USART1_TX",  "-",         "Yes"
-   "D8",  "PA10", "-",     "TIM1_CH3",     "-",          "USART1_RX",  "-",         "Yes"
-   "D9",  "PB7",  "-",     "TIM4_CH2",     "I2C1_SDA",   "-",          "-",         "Yes"
-   "D10", "PA4",  "ADC4",  "-",            "-",          "USART2_CK",  "SPI1_NSS",  "No"
-   "D11", "PA7",  "ADC7",  "TIM3_CH2",     "-",          "-",          "SPI1_MOSI", "No"
-   "D12", "PA6",  "ADC6",  "TIM3_CH1",     "-",          "-",          "SPI1_MISO", "No"
-   "D13", "PA5",  "ADC5",  "-",            "-",          "-",          "SPI1_SCK",  "No"
-   "D14", "PB8",  "-",     "TIM4_CH3",     "-",          "-",          "-",         "Yes"
-   "D15", "PC0",  "ADC10", "-",            "-",          "-",          "-",         "No"
-   "D16", "PC1",  "ADC11", "-",            "-",          "-",          "-",         "No"
-   "D17", "PC2",  "ADC12", "-",            "-",          "-",          "-",         "No"
-   "D18", "PC3",  "ADC13", "-",            "-",          "-",          "-",         "No"
-   "D19", "PC4",  "ADC14", "-",            "-",          "-",          "-",         "No"
-   "D20", "PC5",  "ADC15", "-",            "-",          "-",          "-",         "No"
-   "D21", "PC13", "-",     "-",            "-",          "-",          "-",         "No"
-   "D22", "PC14", "-",     "-",            "-",          "-",          "-",         "No"
-   "D23", "PC15", "-",     "-",            "-",          "-",          "-",         "No"
-   "D24", "PB9",  "-",     "TIM4_CH4",     "-",          "-",          "-",         "Yes"
-   "D25", "PD2",  "-",     "TIM3_ETR",     "-",          "-",          "-",         "Yes"
-   "D26", "PC10", "-",     "-",            "-",          "-",          "-",         "Yes"
-   "D27", "PB0",  "ADC8",  "TIM3_CH3",     "-",          "-",          "-",         "No"
-   "D28", "PB1",  "ADC9",  "TIM3_CH4",     "-",          "-",          "-",         "No"
-   "D29", "PB10", "-",     "-",            "I2C2_SCL",   "USART3_TX",  "-",         "Yes"
-   "D30", "PB11", "-",     "-",            "I2C2_SDA",   "USART3_RX",  "-",         "Yes"
-   "D31", "PB12", "-",     "TIM1_BKIN",    "I2C2_SMBAL", "USART3_CK",  "SPI2_NSS",  "Yes"
-   "D32", "PB13", "-",     "TIM1_CH1N",    "-",          "USART3_CTS", "SPI2_SCK",  "Yes"
-   "D33", "PB14", "-",     "TIM1_CH2N",    "-",          "USART3_RTS", "SPI2_MISO", "Yes"
-   "D34", "PB15", "-",     "TIM1_CH3N",    "-",          "-",          "SPI2_MOSI", "Yes"
-   "D35", "PC6",  "-",     "-",            "-",          "-",          "-",         "Yes"
-   "D36", "PC7",  "-",     "-",            "-",          "-",          "-",         "Yes"
-   "D37", "PC8",  "-",     "-",            "-",          "-",          "-",         "Yes"
+.. * :ref:`Maple Mini <maple-mini-gpios>`
+.. * :ref:`Maple Native <maple-native-gpios>`
+
+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-modes:
 
 GPIO Modes
 ----------
 
+Each of the GPIO pins on a Maple board may be configured using
+pinMode() to behave in a number of ways: as a digital output pin,
+or as an analog input pin, etc., depending on the particular pin.
+
+A ``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 :ref:`board's pin maps <gpio-pin-maps>` and its
+silkscreen for more information on what functionality is available on
+each pin.
+
 .. doxygenenum:: WiringPinMode
 
 Function Reference
@@ -105,7 +73,11 @@ Function Reference
 Recommended Reading
 -------------------
 
-STMicro documentation for STM32F103RB microcontroller:
+* ST Documentation for the STM32F103 series of microcontrollers:
 
-  * `Datasheet <http://www.st.com/stonline/products/literature/ds/13587.pdf>`_ (pdf)
   * `Reference Manual <http://www.st.com/stonline/products/literature/rm/13902.pdf>`_ (pdf)
+
+  * `Programming Manual
+    <http://www.st.com/stonline/products/literature/pm/15491.pdf>`_
+    (PDF; assembly language and register reference)
+