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diff --git a/docs/source/hardware/maple-mini.rst b/docs/source/hardware/maple-mini.rst
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+.. _maple-mini:
+
+Maple Mini
+==========
+
+This page is a general resource for information specific to the Maple
+Mini. The Maple Mini is a smaller version of the Maple that fits on a
+breadboard.
+
+.. contents:: Contents
+ :local:
+
+.. TODO [dma.rst] Ref to dma.rst in sequel instead of libmaple-dma
+
+Technical Specifications
+------------------------
+
+* MCU: :ref:`STM32F103CBT6 <maple-mini-stdocs>`, a 32-bit ARM Cortex
+ M3 microprocessor
+* Clock Speed: **72 MHz**
+* **128 KB Flash** and **20 KB SRAM**
+* 34 :ref:`digital I/ pins (GPIOs) <gpio>`
+* 12 :ref:`PWM <pwm>` pins at 16 bit resolution
+* 9 :ref:`analog input (ADC) <adc>` pins at 12 bit resolution
+* 2 :ref:`SPI <spi>` peripherals
+* 2 :ref:`I2C <i2c>` peripherals
+* 7 Channels of Direct Memory Access (**DMA**) (:ref:`libmaple-dma`)
+* 3 :ref:`USART (serial port) <usart>` peripherals
+* 1 advanced and 3 general-purpose :ref:`timers <timers>`
+* Dedicated :ref:`USB <usb>` port for programming and communications
+* :ref:`jtag`
+* Nested Vectored Interrupt Controller (NVIC) (including
+ :ref:`external interrupt <external-interrupts>` on GPIOs)
+* Supplies up to 500 mA at 3.3 V, with :ref:`separate 250 mA digital
+ and analog regulators <maple-mini-adc-bank>` for low-noise analog
+ performance
+* :ref:`Open source, four layer design <maple-mini-hardware>`
+* Support for low power, sleep, and standby modes (<500 μA)
+* Operating Voltage: 3.3 V
+* Input Voltage (recommended): 3 V — 12 V
+* Dimensions: 2.02″ × 0.72″
+
+.. _maple-mini-powering:
+
+Powering the Maple Mini
+-----------------------
+
+You can power the Maple Mini via the USB plug or by powering Vin
+directly.
+
+.. warning:: The silkscreen on the Maple Mini suggests it will accept
+ an input voltage up to 16 V. We recommend applying **no greater
+ than 12 V**, and potentially even lower depending upon the current
+ draw requirements of the application. Please see :ref:`Power
+ Regulation on the Maple Mini <maple-mini-power-regulation>` for
+ more information.
+
+.. _maple-mini-power-regulation:
+
+Power Regulation on the Maple Mini
+----------------------------------
+
+Power regulation on the Maple is provided by two low dropout linear
+voltage regulators. (The part is the MCP1703 from Microchip, in the
+SOT-23A package. You can download the datasheet `here
+<http://ww1.microchip.com/downloads/en/DeviceDoc/22049a.pdf>`_ ). One
+of the regulators supplies power to the digital voltage plane; the
+other supplies power to the analog voltage plane.
+
+These voltage regulators nominally take an input of up to 16V. In
+addition, while the maximum continuous output current for the board is
+250mA, if you are powering the board off higher voltages the amount
+current it can supply goes down, due to the regulators needing to
+dissipate the extra power. So if you are powering the board off 12V,
+the max current is about 40mA at room temperature. In general (again,
+at room temperature) the max power dissipation (PD) for the chip is
+about .37W, and output current = PD/(Vin-Vout). For exact max current
+calculations, please refer to the datasheet linked above.
+
+If you are planning to draw a lot of current from the Maple board, it
+is necessary to provide input power as close to 3.3V as
+possible. Powering the microcontroller circuitry and LEDs on the board
+alone takes approximately 30mA, so if you are powering the board with
+12V that leaves only 10mA (at best) available for powering any user
+circuitry. Attempting to draw more than 10mA runs the risk of shorting
+out the power regulators and bricking your board.
+
+.. _maple-mini-gpios:
+
+GPIO Information
+----------------
+
+The Maple Mini features 34 total input/output pins, numbered ``D0``
+through ``D33``. These numbers correspond to the numeric values next
+to each header on the Maple Mini's silkscreen. However, some of them
+have special uses by default [#fusedpins]_.
+
+.. _maple-mini-usb-pins:
+
+Pin ``D23`` is the :ref:`USB <usb>` D+ line, and ``D24`` is the USB D-
+line. To use them as GPIOs, your program will need to :ref:`disable
+SerialUSB <lang-serialusb-end>` first. Be aware, however, that
+disabling SerialUSB means that the :ref:`bootloader <bootloader>`
+won't work properly, and you'll need to use
+:ref:`troubleshooting-perpetual-bootloader` to make your next upload.
+
+.. _maple-mini-but:
+
+Pin ``D32`` is the Mini's :ref:`button pin <lang-board-values-but>`.
+It is thus mainly useful as an :ref:`input <lang-pin-levels>`. The
+pin will :ref:`read <lang-digitalread>` ``HIGH`` when the :ref:`button
+is pressed <lang-isbuttonpressed>`.
+
+.. _maple-mini-led:
+
+Pin ``D33`` is the Mini's :ref:`LED pin <lang-board-values-led>`. It
+is thus mainly useful as an :ref:`output <lang-pin-levels>`. The LED
+will glow when ``HIGH`` is :ref:`written <lang-digitalwrite>` to it.
+(It also supports :ref:`pwm`, for finer-grained brightness control).
+
+.. TODO [0.1.0] silkscreen pictures which expand abbreviations
+
+.. _maple-mini-pin-map-master:
+
+Master Pin Map
+^^^^^^^^^^^^^^
+
+This table shows a summary the available functionality on every GPIO
+pin, by peripheral type. The "5 V?" column documents whether or not
+the pin is :ref:`5 volt tolerant <gpio-5v-tolerant>`.
+
+Note that this table is not exhaustive; on some pins, more peripherals
+are available than are listed here.
+
+.. csv-table::
+ :header: Pin, :ref:`GPIO <gpio>`, :ref:`ADC <adc>`, :ref:`Timer <timers>`, :ref:`I2C <i2c>`, :ref:`UART <usart>`, :ref:`SPI <spi>`, 5 V?
+
+ D0, PB11, -, -, 2_SDA, 3_RX, -, Yes
+ D1, PB10, -, -, 2_SCL, 3_TX, -, Yes
+ D2, PB2, -, -, -, -, -, Yes
+ D3, PB0, CH8, 3_CH3, -, -, -, -
+ D4, PA7, CH7, 3_CH2, -, -, 1_MOSI, -
+ D5, PA6, CH6, 3_CH1, -, -, 1_MISO, -
+ D6, PA5, CH5, -, -, -, 1_SCK, -
+ D7, PA4, CH4, -, -, 2_CK, 1_NSS, -
+ D8, PA3, CH3, 2_CH4, -, 2_RX, -, -
+ D9, PA2, CH2, 2_CH3, -, 2_TX, -, -
+ D10, PA1, CH1, 2_CH2, -, 2_RTS, -, -
+ D11, PA0, CH0, 2_CH1_ETR, -, 2_CTS, -, -
+ D12, PC15, -, -, -, -, -, -
+ D13, PC14, -, -, -, -, -, -
+ D14, PC13, -, -, -, -, -, -
+ D15, PB7, -, 4_CH2, 1_SDA, -, -, Yes
+ D16, PB6, -, 4_CH1, 2_SCL, -, -, Yes
+ D17, PB5, -, -, 1_SMBA, -, -, -
+ D18, PB4, -, -, -, -, -, Yes
+ D19, PB3, -, -, -, -, -, Yes
+ D20, PA15, -, -, -, -, -, Yes
+ D21, PA14, -, -, -, -, -, Yes
+ D22, PA13, -, -, -, -, -, Yes
+ D23, PA12, -, 1_ETR, -, 1_RTS, -, Yes
+ D24, PA11, -, 1_CH4, -, 1_CTS, -, Yes
+ D25, PA10, -, 1_CH3, -, 1_RX, -, Yes
+ D26, PA9, -, 1_CH2, -, 1_TX, -, Yes
+ D27, PA8, -, 1_CH1, -, 1_CK, -, Yes
+ D28, PB15, -, -, -, -, 2_MOSI, Yes
+ D29, PB14, -, -, -, 3_RTS, 2_MISO, Yes
+ D30, PB13, -, -, -, 3_CTS, 2_SCK, Yes
+ D31, PB12, -, 1_BKIN, 2_SMBA, 3_CK, 2_NSS, Yes
+ D32, PB8, -, 4_CH3, -, -, -, Yes
+ D33, PB1, CH9, 3_CH4, -, -, -, -
+
+.. _maple-mini-gpio-port-map:
+
+GPIO Port Pin Map
+^^^^^^^^^^^^^^^^^
+The following table shows what pins are associated with each
+:ref:`GPIO port <gpio-ports>`.
+
+.. csv-table::
+ :header: GPIOA, GPIOB, GPIOC
+
+ PA0: D11, PB0: D3, PC0: -
+ PA1: D10, PB1: D33, PC1: -
+ PA2: D9, PB2: D2, PC2: -
+ PA3: D8, PB3: D19, PC3: -
+ PA4: D7, PB4: D18, PC4: -
+ PA5: D6, PB5: D17, PC5: -
+ PA6: D5, PB6: D16, PC6: -
+ PA7: D4, PB7: D15, PC7: -
+ PA8: D27, PB8: D32, PC8: -
+ PA9: D26, PB9: -, PC9: -
+ PA10: D25, PB10: D1, PC10: -
+ PA11: D24, PB11: D0, PC11: -
+ PA12: D23, PB12: D31, PC12: -
+ PA13: D22, PB13: D30, PC13: D14
+ PA14: D21, PB14: D29, PC14: D13
+ PA15: D20, PB15: D28, PC15: D12
+
+.. _maple-mini-timer-map:
+
+Timer Pin Map
+^^^^^^^^^^^^^
+
+The following table shows what pins are associated with a particular
+timer's capture/compare channels.
+
+.. csv-table::
+ :header: Timer, Ch. 1, Ch. 2, Ch. 3, Ch. 4
+ :delim: |
+
+ 1 | D27 | D26 | D25 | D24
+ 2 | D11 | D10 | D9 | D8
+ 3 | D5 | D4 | D3 | :ref:`D33 <maple-mini-led>`
+ 4 | D16 | D15 | :ref:`D32 <maple-mini-but>` |
+
+.. _maple-mini-exti-map:
+
+EXTI Line Pin Map
+^^^^^^^^^^^^^^^^^
+
+The following table shows which pins connect to which :ref:`EXTI lines
+<external-interrupts-exti-line>`.
+
+.. list-table::
+ :widths: 1 1
+ :header-rows: 1
+
+ * - EXTI Line
+ - Pins
+ * - EXTI0
+ - D3, D11
+ * - EXTI1
+ - D10, D33
+ * - EXTI2
+ - D2, D9
+ * - EXTI3
+ - D8, D19
+ * - EXTI4
+ - D7, D18
+ * - EXTI5
+ - D6, D17
+ * - EXTI6
+ - D5, D16
+ * - EXTI7
+ - D4, D15
+ * - EXTI8
+ - D27, D32
+ * - EXTI9
+ - D26
+ * - EXTI10
+ - D1, D25
+ * - EXTI11
+ - D0, D24
+ * - EXTI12
+ - D23, D31
+ * - EXTI13
+ - D14, D22, D30
+ * - EXTI14
+ - D13, D21, D29
+ * - EXTI15
+ - D12, D20, D28
+
+.. _maple-mini-usart-map:
+
+USART Pin Map
+^^^^^^^^^^^^^
+
+The Maple Mini has three serial ports (also known as :ref:`USARTs
+<usart>`). They communicate using the pins given in the following
+table.
+
+.. csv-table::
+ :header: Serial Port, TX, RX, CK, CTS, RTS
+ :delim: |
+
+ ``Serial1`` | D26 | D25 | D27 | D24 | D23
+ ``Serial2`` | D9 | D8 | D7 | D11 | D10
+ ``Serial3`` | D1 | D0 | D31 | D30 | D29
+
+.. _maple-mini-adc-bank:
+
+Low-Noise ADC Pins
+^^^^^^^^^^^^^^^^^^
+
+Maple Mini has an electrically isolated analog power plane with its
+own regulator, and a geometrically isolated ground plane, connected to
+the digital plane by an inductor. Its analog input pins, D3 — D11,
+are laid out to correspond with these analog planes, and our
+measurements indicate that they generally offer low noise ADC
+performance. However, analog performance may vary depending upon the
+activity of the other GPIOs. Consult the :ref:`Maple Mini hardware
+design files <maple-mini-hardware>` for more details.
+
+.. _maple-mini-board-values:
+
+Board-Specific Values
+---------------------
+
+This section lists the Maple Mini's :ref:`board-specific values
+<lang-board-values>`.
+
+- ``CYCLES_PER_MICROSECOND``: 72
+- ``BOARD_BUTTON_PIN``: 32
+- ``BOARD_LED_PIN``: 33
+- ``BOARD_NR_GPIO_PINS``: 34
+- ``BOARD_NR_PWM_PINS``: 12
+- ``boardPWMPins``: 3, 4, 5, 8, 9, 10, 11, 15, 16, 25, 26, 27
+- ``BOARD_NR_ADC_PINS``: 9
+- ``boardADCPins``: 3, 4, 5, 6, 7, 8, 9, 10, 11
+- ``BOARD_NR_USED_PINS``: 4
+- ``boardUsedPins``: ``BOARD_LED_PIN``, ``BOARD_BUTTON_PIN``, 23, 24
+ (23 and 24 are used by :ref:`USB <maple-mini-usb-pins>`)
+- ``BOARD_NR_USARTS``: 3
+- ``BOARD_USART1_TX_PIN``: 26
+- ``BOARD_USART1_RX_PIN``: 25
+- ``BOARD_USART2_TX_PIN``: 9
+- ``BOARD_USART2_RX_PIN``: 8
+- ``BOARD_USART3_TX_PIN``: 1
+- ``BOARD_USART3_RX_PIN``: 0
+- ``BOARD_NR_SPI``: 2
+- ``BOARD_SPI1_NSS_PIN``: 7
+- ``BOARD_SPI1_MOSI_PIN``: 4
+- ``BOARD_SPI1_MISO_PIN``: 5
+- ``BOARD_SPI1_SCK_PIN``: 6
+- ``BOARD_SPI2_NSS_PIN``: 31
+- ``BOARD_SPI2_MOSI_PIN``: 28
+- ``BOARD_SPI2_MISO_PIN``: 29
+- ``BOARD_SPI2_SCK_PIN``: 30
+- ``BOARD_JTMS_SWDIO_PIN``: 22
+- ``BOARD_JTCK_SWCLK_PIN``: 21
+- ``BOARD_JTDI_PIN``: 20
+- ``BOARD_JTDO_PIN``: 19
+- ``BOARD_NJTRST_PIN``: 18
+
+.. _maple-mini-hardware:
+
+Hardware Design Files
+---------------------
+
+The hardware schematics and board layout files are available in the
+`Maple Mini GitHub repository <https://github.com/leaflabs/maplemini>`_.
+
+From the GitHub repository main page, you can download the entire
+repository by clicking the "Download" button. If you are familiar
+with `Git <http://git-scm.com/>`_, you can also clone the repository
+at the command line with ::
+
+ $ git clone git://github.com/leaflabs/maplemini.git
+
+Failure Modes
+-------------
+
+The following known failure modes apply to all Maple boards. The
+failure modes aren't design errors, but are easy ways to break or
+damage your board permanently.
+
+* **High voltage on non-tolerant pins**: not all header pins are 5 V
+ compatible; so e.g. connecting certain serial devices in the wrong
+ way could over-voltage the pins. The :ref:`pin-mapping master table
+ <maple-mini-pin-map-master>` details which pins are :ref:`5
+ V-tolerant <gpio-5v-tolerant>`.
+
+Errata
+------
+
+This section lists known issues and warnings for the Maple Mini Rev 2
+(the first Rev sold to the public).
+
+.. _maple-mini-vin:
+
+* **Silkscreen Vin voltage mistake**: The silkscreen on the Maple Mini
+ falsely indicates that Vin may be supplied with up to 16V. We
+ recommend an input voltage **no greater than 12V**, and potentially
+ even lower depending upon the current draw requirements of the
+ application. Please see :ref:`Power Regulation on the Maple Mini
+ <maple-mini-power-regulation>` for more information.
+
+
+Recommended Reading
+-------------------
+
+.. _maple-mini-stdocs:
+
+STMicro documentation for STM32F103CB microcontroller:
+
+* `Datasheet
+ <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00161566.pdf>`_
+ (PDF); covers STM32F103x8, STM32F103xB.
+* `Reference Manual RM0008
+ <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/REFERENCE_MANUAL/CD00171190.pdf>`_
+ (PDF); definitive resource for peripherals on the 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.
+* `STM32F103CB <http://www.st.com/internet/mcu/product/189782.jsp>`_
+ overview page with links to further references.
+
+.. rubric:: Footnotes
+
+.. [#fusedpins] See :ref:`boardUsedPins <lang-board-values-used-pins>`
+ for more information.
diff --git a/docs/source/hardware/maple-native-beta.rst b/docs/source/hardware/maple-native-beta.rst
new file mode 100644
index 0000000..bdfd216
--- /dev/null
+++ b/docs/source/hardware/maple-native-beta.rst
@@ -0,0 +1,605 @@
+.. highlight:: sh
+
+.. _maple-native-b:
+
+Maple Native β
+==============
+
+This page is a general resource for information specific to the Maple
+Native Beta. Since this is a beta release, the information here may
+change slightly between now and the final Maple Native release.
+
+.. contents:: Contents
+ :local:
+
+Technical Specifications
+------------------------
+
+* MCU: `STM32F103ZET6 <maple-native-b-stdocs>`, a 32-bit ARM Cortex M3
+ microprocessor.
+* Clock Speed: **72 MHz**
+* **512 KB Flash**, **64 KB SRAM** (on-chip), **1 MB SRAM** (external)
+* 106 :ref:`digital I/O pins <gpio>`
+* 17 :ref:`PWM <pwm>` pins at 16 bit resolution
+* 21 :ref:`analog input (ADC) <adc>` pins at 12-bit resolution
+* 3 :ref:`SPI <spi>` peripherals
+* 2 :ref:`I2C <i2c>` peripherals
+* 12 Channels of Direct Memory Access (**DMA**) (:ref:`libmaple-dma`)
+ with 2 DMA controllers
+* 3 :ref:`USART (serial port) <usart>` peripherals, 2 **UART** peripherals
+* 2 advanced, 4 general-purpose, and 2 basic :ref:`timers <timers>`
+* Dedicated :ref:`USB <usb>` port for programming and communications
+* :ref:`JTAG <jtag>`
+* Nested Vectored Interrupt Controller (NVIC) (including
+ :ref:`external interrupt <lang-attachinterrupt>` on GPIOs)
+* Supplies up to 500 mA at 3.3 V, with :ref:`separate 250 mA digital
+ and analog regulators <maple-native-b-adc-bank>` for low-noise analog
+ performance
+* :ref:`Open-source, four layer design <maple-native-b-hardware>`
+* Support for low power, sleep, and standby modes (<500 μA)
+* Operating Voltage: 3.3 V
+* Input Voltage (recommended): 3 V — 12 V
+* Dimensions: 4″ × 2.1″
+
+.. _maple-native-b-powering:
+
+Powering the Maple Native
+-------------------------
+
+The power source is determined by the header labeled "PWRSEL" on the
+silkscreen. The Maple Native may be powered from USB (marked "USB" on
+the PWRSEL header), a LiPo battery (marked "BAT"), or one of the two
+"Vin" pins (marked "EXT"). Boards are shipped with a jumper on the
+USB selector. In order to power it off of an alternative source,
+unplug the Maple Native, then move the jumper to the desired selector
+before reconnecting power.
+
+The "Vin" line is available on the pin labeled "Vin" on the vertical
+header to the right of the PWRSEL header, as well as on the
+unpopulated two-pin connector on the upper left corner of the
+board. On this latter connector, polarity was accidentally left
+unmarked: the leftmost, round pin should be power, while the square
+pin should be ground.
+
+When powering the Maple Native board from a battery or the Vin lines,
+care must be taken not to over-voltage the board. In general, an upper
+limit of 12V input is acceptable, but this may vary depending upon the
+current draw requirements of the application. Please see :ref:`Power
+Regulation on the Maple Native <maple-native-b-power-regulation>` for
+more information.
+
+.. _maple-native-b-power-regulation:
+
+Power Regulation on the Maple Native
+------------------------------------
+
+Power regulation on the Maple Native is provided by two low dropout
+linear voltage regulators. (The part is the MCP1703 from Microchip, in
+the SOT-23A package. You can download the datasheet `here
+<http://ww1.microchip.com/downloads/en/DeviceDoc/22049a.pdf>`_). One
+of the regulators supplies power to the digital voltage plane; the
+other supplies power to the analog voltage plane.
+
+These voltage regulators nominally take an input of up to 16V. In
+addition, while the maximum continuous output current for the board is
+250mA, if you are powering the board off higher voltages the current
+it can supply goes down, due to the regulators needing to dissipate
+the extra power. So if you are powering the board off 12V, the max
+current is about 40mA at room temperature. In general (again, at room
+temperature) the max power dissipation (PD) for the chip is about
+.37W, and output current = PD/(Vin-Vout). For exact max current
+calculations, please refer to the datasheet linked above.
+
+If you are planning to draw a lot of current from the Maple Native
+board, it is necessary to provide input power as close to 3.3V as
+possible. Powering the microcontroller circuitry and LEDs on the board
+alone takes approximately 30mA, so if you are powering the board with
+12V that leaves only 10mA (at best) available for powering any user
+circuitry. Attempting to draw more than 10mA runs the risk of shorting
+out the power regulators and bricking your board.
+
+Using the Built-in Battery Charger
+----------------------------------
+
+Maple Native includes a built-in LiPo battery charger. In order to
+use it, put a jumper across the CHRG selector on the PWRSEL header and
+across the USB, or EXT selectors, depending on whether you're charging
+the battery via USB cable or Vin, respectively. The LED labeled CHRG
+will light up while the battery is being charged. When the battery is
+finished charging, the LED labeled DONE will light up.
+
+.. _maple-native-b-gpios:
+
+GPIO Information
+----------------
+
+The Maple Native features 106 total input/output pins, numbered ``D0``
+through ``D105``. In most cases, these numbers correspond to the
+numeric values next to each header on the Maple Native's silkscreen.
+However, pins ``D101`` through ``D105`` are broken out to the
+:ref:`JTAG <jtag>` header, and are not numbered on the silkscreen. In
+addition, some other pins have other uses by default [#fusedpins]_.
+
+.. _maple-native-b-but:
+
+Pin ``D6`` is the Native's :ref:`button pin <lang-board-values-but>`.
+It is thus mainly useful as an :ref:`input <lang-pin-levels>`. The
+pin will :ref:`read <lang-digitalread>` ``HIGH`` when the :ref:`button
+is pressed <lang-isbuttonpressed>`.
+
+.. _maple-native-b-led:
+
+Pin ``D22`` is the Native's :ref:`LED pin <lang-board-values-led>`.
+It is thus mainly useful as an :ref:`output <lang-pin-levels>`. The
+LED will glow when ``HIGH`` is :ref:`written <lang-digitalwrite>` to
+it.
+
+.. _maple-native-b-fsmc:
+
+Many of the pins on the right header (pins ``D56`` through ``D100``,
+the header is labeled :ref:`"FSMC" <fsmc>` on the silkscreen) are
+connected to the SRAM chip. Using these pins as GPIOs may render the
+memory chip useless, which can cause your program to crash. For this
+reason, we don't recommend that you use these pins unless you know
+what you are doing. The following pins on the right header are not
+connected to the SRAM and may be used with impunity: ``D57``, ``D60``,
+``D63``, ``D66``, ``D69``, ``D72``, ``D75``, ``D80``, ``D83``.
+
+.. _maple-native-b-jtag:
+
+Pins ``D101`` through ``D105`` are connected to the pads on the
+:ref:`JTAG <jtag>` header. In order to use them as GPIOs, you must
+first disable the Maple Native's debug ports. You can do this by
+calling :ref:`lang-disabledebugports`. (Note that this means you
+won't be able to use JTAG or SW-Debug to debug your program).
+
+.. TODO [0.1.0] silkscreen pictures
+
+.. _maple-native-b-pin-map-master:
+
+Master Pin Map
+^^^^^^^^^^^^^^
+
+This table shows a summary the available functionality on every GPIO
+pin, by peripheral type. The "5 V?" column documents whether or not
+the pin is :ref:`5 volt tolerant <gpio-5v-tolerant>`.
+
+Note that this table is not exhaustive; on some pins, more peripherals
+are available than are listed here.
+
+**Top header:**
+
+.. csv-table::
+ :header: Pin, :ref:`GPIO <gpio>`, :ref:`ADC <adc>`, :ref:`Timer <timers>`, :ref:`I2C <i2c>`, :ref:`UART <usart>`, :ref:`SPI <spi>`, 5 V?
+
+ D0, PB10, -, -, 2_SCL, 3_TX, -, Yes
+ D1, PB11, -, -, 2_SDA, 3_RX, -, Yes
+ D2, PB12, -, 1_BKIN, 2_SMBA, 3_CK, 2_NSS, Yes
+ D3, PB13, -, -, -, 3_CTS, 2_SCK, Yes
+ D4, PB14, -, -, -, 3_RTS, 2_MISO, Yes
+ D5, PB15, -, -, -, -, 2_MOSI, Yes
+ D6, PG15, -, -, -, -, -, Yes
+ D7, PC0, 1_CH10, -, -, -, -, -
+ D8, PC1, 1_CH11, -, -, -, -, -
+ D9, PC2, 1_CH12, -, -, -, -, -
+ D10, PC3, 1_CH13, -, -, -, -, -
+ D11, PC4, 1_CH14, -, -, -, -, -
+ D12, PC5, 1_CH15, -, -, -, -, -
+ D13, PC6, -, 8_CH1, -, -, -, Yes
+ D14, PC7, -, 8_CH2, -, -, -, Yes
+ D15, PC8, -, 8_CH3, -, -, -, Yes
+ D16, PC9, -, 8_CH4, -, -, -, Yes
+ D17, PC10, -, -, -, 4_TX, -, Yes
+ D18, PC11, -, -, -, 4_RX, -, Yes
+ D19, PC12, -, -, -, 5_TX, -, Yes
+ D20, PC13, -, -, -, -, -, -
+ D21, PC14, -, -, -, -, -, -
+ D22, PC15, -, -, -, -, -, -
+ D23, PA8, -, 1_CH1, -, 1_CK, -, Yes
+ D24, PA9, -, 1_CH2, -, 1_TX, -, Yes
+ D25, PA10, -, 1_CH3, -, 1_RX, -, Yes
+ D26, PB9, -, 4_CH4, -, -, -, Yes
+
+**Bottom header:**
+
+.. note:: ``D48``, ``D49``, ``D50``, ``D51`` are also connected to
+ Timer 2 channels 1, 2, 3, and 4, respectively.
+
+.. csv-table::
+ :header: Pin, :ref:`GPIO <gpio>`, :ref:`ADC <adc>`, :ref:`Timer <timers>`, :ref:`I2C <i2c>`, :ref:`UART <usart>`, :ref:`SPI <spi>`, 5 V?
+
+ D27, PD2, -, 3_ETR, -, 5_RX, -, Yes
+ D28, PD3, -, -, -, -, -, Yes
+ D29, PD6, -, -, -, -, -, Yes
+ D30, PG11, -, -, -, -, -, Yes
+ D31, PG12, -, -, -, -, -, Yes
+ D32, PG13, -, -, -, -, -, Yes
+ D33, PG14, -, -, -, -, -, Yes
+ D34, PG8, -, -, -, -, -, Yes
+ D35, PG7, -, -, -, -, -, Yes
+ D36, PG6, -, -, -, -, -, Yes
+ D37, PB5, -, -, 1_SMBA, -, 3_MOSI, -
+ D38, PB6, -, 4_CH1, 1_SCL, -, -, Yes
+ D39, PB7, -, 4_CH2, 1_SDA, -, -, Yes
+ D40, PF11, -, -, -, -, -, Yes
+ D41, PF6, 3_CH4, -, -, -, -, -
+ D42, PF7, 3_CH5, -, -, -, -, -
+ D43, PF8, 3_CH6, -, -, -, -, -
+ D44, PF9, 3_CH7, -, -, -, -, -
+ D45, PF10, 3_CH8, -, -, -, -, -
+ D46, PB1, 1_CH9, 3_CH4, -, -, -, -
+ D47, PB0, 1_CH8, 3_CH3, -, -, -, -
+ D48, PA0, 1_CH0, 5_CH1, -, 2_CTS, -, -
+ D49, PA1, 1_CH1, 5_CH2, -, 2_RTS, -, -
+ D50, PA2, 1_CH2, 5_CH3, -, 2_TX, -, -
+ D51, PA3, 1_CH3, 5_CH4, -, 2_RX, -, -
+ D52, PA4, 1_CH4, -, -, 2_CK, 1_NSS, -
+ D53, PA5, 1_CH5, -, -, -, 1_SCK, -
+ D54, PA6, 1_CH6, 3_CH1, -, -, 1_MISO, -
+ D55, PA7, 1_CH7, 3_CH2, -, -, 1_MOSI, -
+
+.. _maple-native-b-fsmc-map:
+
+**Right (FSMC) header**
+
+All of the following pins are 5V-tolerant. Note that in the "FSMC"
+column below, entries with a "Dn" value (D0, D1, etc.) don't refer to
+pins; they refer to FSMC data lines. See :ref:`RM0008
+<maple-native-b-stdocs>` for more information.
+
+.. warning:: Many of the pins on this header are used by the Maple
+ Native's SRAM chip. Don't use them as GPIOs unless you know what
+ you're doing, or your program may crash. :ref:`See above
+ <maple-native-b-fsmc>` for more information.
+
+.. csv-table::
+ :header: Pin, :ref:`GPIO <gpio>`, :ref:`FSMC <fsmc>`
+
+ D56, PF0, A0
+ D57, PD11, A16
+ D58, P14, D0
+ D59, PF1, A1
+ D60, PD12, A17
+ D61, PD15, D1
+ D62, PF2, A2
+ D63, PD13, A18
+ D64, PD0, D2
+ D65, PF3, A3
+ D66, PE3, A19
+ D67, PD1, D3
+ D68, PF4, A4
+ D69, PE4, A20
+ D70, PE7, D4
+ D71, PF5, A5
+ D72, PE5, A21
+ D73, PE8, D8
+ D74, PF12, A6
+ D75, PE6, A22
+ D76, PE9, D6
+ D77, PF13, A7
+ D78, PE10, D7
+ D79, PF14, A8
+ D80, PG9, NE2/NCE3
+ D81, PE11, D8
+ D82, PF15, A9
+ D83, PG10, NCE4_1/NE3/NCE4_2
+ D84, PE12, D9
+ D85, PG0, A10
+ D86, PD5, NWE
+ D87, PE13, D10
+ D88, PG1, A11
+ D89, PD4, NOE
+ D90, PE14, D11
+ D91, PG2, A12
+ D92, PE1, NBL1
+ D93, PE15, D12
+ D94, PG3, A13
+ D95, PE0, NBL0
+ D96, PD8, D13
+ D97, PG4, A14
+ D98, PD9, D14
+ D99, PG5, A15
+ D100, PD10, D15
+
+**JTAG header pins**
+
+.. note:: See :ref:`above <maple-native-b-jtag>` for more information on
+ these pins.
+
+.. csv-table::
+ :header: Pin, :ref:`GPIO <gpio>`, :ref:`SPI <spi>`, 5 V?
+
+ D101, PA13, -, Yes
+ D102, PA14, -, Yes
+ D103, PA15, 3_NSS, Yes
+ D104, PB3, 3_SCK, Yes
+ D105, PB4, 3_MISO, Yes
+
+.. _maple-native-b-gpio-port-map:
+
+GPIO Port Pin Map
+^^^^^^^^^^^^^^^^^
+
+The following tables show what pins are associated with each
+:ref:`GPIO port <gpio-ports>`.
+
+.. csv-table::
+ :header: GPIOA, GPIOB, GPIOC, GPIOD
+
+ PA0: D48, PB0: D47, PC0: D7, PD0: D64
+ PA1: D49, PB1: D46, PC1: D8, PD1: D67
+ PA2: D50, PB2: -, PC2: D9, PD2: D27
+ PA3: D51, PB3: D104, PC3: D10, PD3: D28
+ PA4: D52, PB4: D105, PC4: D11, PD4: D89
+ PA5: D53, PB5: D37, PC5: D12, PD5: D86
+ PA6: D54, PB6: D38, PC6: D13, PD6: D29
+ PA7: D55, PB7: D39, PC7: D14, PD7: -
+ PA8: D23, PB8: -, PC8: D15, PD8: D96
+ PA9: D24, PB9: D26, PC9: D16, PD9: D98
+ PA10: D25, PB10: D0, PC10: D17, PD10: D100
+ PA11: -, PB11: D1, PC11: D18, PD11: D57
+ PA12: -, PB12: D2, PC12: D19, PD12: D60
+ PA13: D101, PB13: D3, PC13: D20, PD13: D63
+ PA14: D102, PB14: D4, PC14: D21, PD14: D58
+
+.. csv-table::
+ :header: GPIOE, GPIOF, GPIOG
+
+ PE0: D95, PF0: D56, PG0: D85
+ PE1: D92, PF1: D59, PG1: D88
+ PE2: - PF2: D62, PG2: D91,
+ PE3: D66, PF3: D65, PG3: D94
+ PE4: D69, PF4: D68, PG4: D97
+ PE5: D72, PF5: D71, PG5: D99
+ PE6: D75, PF6: D41, PG6: D36
+ PE7: D70, PF7: D42, PG7: D35
+ PE8: D73, PF8: D43, PG8: D34
+ PE9: D76, PF9: D44, PG9: D80
+ PE10: D78, PF10: D45, PG10: D83
+ PE11: D81, PF11: D40, PG11: D30
+ PE12: D84, PF12: D74, PG12: D31
+ PE13: D87, PF13: D77, PG13: D32
+ PE14: D90, PF14: D79, PG14: D33
+
+.. _maple-native-b-timer-map:
+
+Timer Pin Map
+^^^^^^^^^^^^^
+
+The following table shows what pins are associated with a particular
+timer's capture/compare channels.
+
+There is no mistake between timers 2 and 5. They really do share
+those pins. If you like, you can remap some of the timer 2 channels
+to get extra PWM pins; see :ref:`afio_remap() (in gpio.h)
+<gpio-h-afio-remap>`.
+
+.. csv-table::
+ :header: Timer, Ch. 1, Ch. 2, Ch. 3, Ch. 4
+ :delim: |
+
+ 1 | D23 | D24 | D25 |
+ 2 | D48 | D49 | D50 | D51
+ 3 | D54 | D55 | D47 | D46
+ 4 | D38 | D39 | | D26
+ 5 | D48 | D49 | D50 | D51
+ 8 | D13 | D14 | D15 | D16
+
+.. _maple-native-b-exti-map:
+
+EXTI Line Pin Map
+^^^^^^^^^^^^^^^^^
+
+The following table shows which pins connect to which :ref:`EXTI lines
+<external-interrupts-exti-line>`.
+
+.. list-table::
+ :widths: 1 3
+ :header-rows: 1
+
+ * - EXTI Line
+ - Pins
+ * - EXTI0
+ - D7, D47, D48, D56, D64, D85, D95
+ * - EXTI1
+ - D8, D46, D49, D59, D67, D88, D92
+ * - EXTI2
+ - D9, D27, D50, D62, D91
+ * - EXTI3
+ - D10, D28, D51, D65, D66, D94, D104
+ * - EXTI4
+ - D11, D52, D68, D69, D89, D97, D105
+ * - EXTI5
+ - D12, D37, D53, D71, D72, D86, D99
+ * - EXTI6
+ - D13, D29, D36, D38, D41, D54, D75
+ * - EXTI7
+ - D14, D35, D39, D42, D55, D70
+ * - EXTI8
+ - D15, D23, D34, D43, D73, D96
+ * - EXTI9
+ - D16, D24, D26, D44, D76, D80, D98
+ * - EXTI10
+ - D0, D17, D25, D45, D78, D83, D100
+ * - EXTI11
+ - D1, D18, D30, D40, D57, D81
+ * - EXTI12
+ - D2, D19, D31, D60, D74, D84
+ * - EXTI13
+ - D3, D20, D32, D63, D77, D87, D101
+ * - EXTI14
+ - D4, D21, D33, D58, D79, D90, D102
+ * - EXTI15
+ - D5, D6, D22, D61, D82, D93, D103
+
+.. _maple-native-b-usart-map:
+
+USART Pin Map
+^^^^^^^^^^^^^
+
+The Maple Native has 3 :ref:`USART <usart>` serial ports. They
+communicate using the pins given in the following table.
+
+.. csv-table::
+ :header: Serial port, TX, RX, CK, CTS, RTS
+ :delim: |
+
+ ``Serial1`` | D24 | D25 | D23 | |
+ ``Serial2`` | D50 | D51 | D52 | D48 | D49
+ ``Serial3`` | D0 | D1 | D2 | D3 | D4
+
+The Maple Native also has 2 UART serial ports. Unlike USARTS, these
+only communicate asynchronously, and thus only have TX and RX pins.
+These are given in the following table.
+
+.. csv-table::
+ :header: Serial port, TX, RX
+ :delim: |
+
+ ``Serial4`` | D17 | D18
+ ``Serial5`` | D19 | D27
+
+.. _maple-native-b-adc-bank:
+
+Low-Noise ADC Pins
+^^^^^^^^^^^^^^^^^^
+
+There are fifteen pins at the bottom right of the board (``D41`` —
+``D55``) that generally offer lower-noise ADC performance than other
+pins on the board. If you're concerned about getting good ADC
+readings, we recommend using one of these pins to take your
+measurements.
+
+Maple Native has an electrically isolated analog power plane with its
+own regulator, and a geometrically isolated ground plane. Analog input
+pins D41 — D55 are laid out to correspond with these analog planes,
+and our measurements indicate that they generally ofer low noise ADC
+performance. However, analog performance may vary depending upon the
+activity of other GPIOs. In particular, using PWM on any of pins
+``D46`` — ``D51``, ``D54``, and ``D55`` may cause digital noise.
+Consult the :ref:`Maple Native beta hardware design files
+<maple-native-b-hardware>` for more details.
+
+.. _maple-native-b-board-values:
+
+Board-Specific Values
+---------------------
+
+This section lists the Maple Native's :ref:`board-specific values
+<lang-board-values>`.
+
+- ``CYCLES_PER_MICROSECOND``: 72
+- ``BOARD_BUTTON_PIN``: 6
+- ``BOARD_LED_PIN``: 22
+- ``BOARD_NR_GPIO_PINS``: 106
+- ``BOARD_NR_PWM_PINS``: 18
+- ``boardPWMPins``: 13, 14, 15, 16, 23, 24, 25, 26, 38, 39, 46, 47,
+ 48, 49, 50, 51, 54, 55
+- ``BOARD_NR_ADC_PINS``: 21
+- ``boardADCPins``: 7, 8, 9, 10, 11, 12, 41, 42, 43, 44, 45, 46, 47,
+ 48, 49, 50, 51, 52, 53, 54, 55
+- ``BOARD_NR_USED_PINS``: 43
+- ``boardUsedPins``: ``BOARD_LED_PIN``, ``BOARD_BUTTON_PIN``,
+ ``BOARD_JTMS_SWDIO_PIN``, ``BOARD_JTCK_SWCLK_PIN``,
+ ``BOARD_JTDI_PIN``, ``BOARD_JTDO_PIN``, ``BOARD_NJTRST_PIN``, and
+ all pins on FSMC header except those mentioned :ref:`above
+ <maple-native-b-fsmc>`.
+- ``BOARD_NR_USARTS``: 5
+- ``BOARD_USART1_TX_PIN``: 24
+- ``BOARD_USART1_RX_PIN``: 25
+- ``BOARD_USART2_TX_PIN``: 50
+- ``BOARD_USART2_RX_PIN``: 51
+- ``BOARD_USART3_TX_PIN``: 0
+- ``BOARD_USART3_RX_PIN``: 1
+- ``BOARD_UART4_TX_PIN``: 17
+- ``BOARD_UART4_RX_PIN``: 18
+- ``BOARD_UART5_TX_PIN``: 19
+- ``BOARD_UART5_RX_PIN``: 27
+- ``BOARD_NR_SPI``: 3
+- ``BOARD_SPI1_NSS_PIN``: 52
+- ``BOARD_SPI1_MOSI_PIN``: 55
+- ``BOARD_SPI1_MISO_PIN``: 54
+- ``BOARD_SPI1_SCK_PIN``: 53
+- ``BOARD_SPI2_NSS_PIN``: 2
+- ``BOARD_SPI2_MOSI_PIN``: 5
+- ``BOARD_SPI2_MISO_PIN``: 4
+- ``BOARD_SPI2_SCK_PIN``: 3
+- ``BOARD_SPI3_NSS_PIN``: 103 (on :ref:`JTAG header <maple-native-b-jtag>`)
+- ``BOARD_SPI3_MOSI_PIN``: 37
+- ``BOARD_SPI3_MISO_PIN``: 105 (JTAG header)
+- ``BOARD_SPI3_SCK_PIN``: 104 (JTAG header)
+- ``BOARD_JTMS_SWDIO_PIN``: :ref:`103 <maple-native-b-jtag>`
+- ``BOARD_JTCK_SWCLK_PIN``: 102
+- ``BOARD_JTDI_PIN``: 103
+- ``BOARD_JTDO_PIN``: 104
+- ``BOARD_NJTRST_PIN``: 105
+
+.. _maple-native-b-hardware:
+
+Hardware Design Files
+^^^^^^^^^^^^^^^^^^^^^
+
+The hardware schematics and board layout files are available in the
+`Maple Native GitHub repository
+<https://github.com/leaflabs/maplenative/>`_. Download the `beta
+version's hardware design files
+<https://github.com/leaflabs/maplenative/tree/beta>`_ (ZIP format).
+
+If you're familiar with Git, you can clone the entire repository and
+checkout the commit tagged "beta" using the following::
+
+ $ git clone git://github.com/leaflabs/maplenative.git
+ $ git checkout beta
+
+Failure Modes
+-------------
+
+The following known failure modes apply to the Maple Native Beta. The
+failure modes aren't design errors, but are easy ways to break or
+damage your board permanently.
+
+* **Reversing Vin and GND**: when powering the Maple Native Beta via
+ the Vin and ground (GND) pins at the top left of the board, it is
+ possible to carelessly cause a short or switch the connections,
+ applying the high voltage to GND and ground to Vin.
+
+ If this happens, you will reverse bias the diode beneath these pins,
+ most likely damaging it. This may cause excess voltage to
+ subsequently be delivered to the board once the reversed pins are
+ connected properly.
+
+Errata
+------
+
+This section lists known issues and warnings for the Maple Native
+Beta.
+
+* **PWM on pin 39**: PWM on pin 39 appears to be nonfunctional. We
+ are looking into this issue.
+
+* **VREF is nonfunctional**: Due to a routing error, VREF is
+ permanently tied to 3.3V at VAA.
+
+Recommended Reading
+-------------------
+
+.. _maple-native-b-stdocs:
+
+STMicro documentation for STM32F103ZE microcontroller:
+
+* `Datasheet
+ <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00191185.pdf>`_
+ (PDF); covers STM32F103xC, STM3F103xD, STM32F103xE.
+* `Reference Manual RM0008
+ <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/REFERENCE_MANUAL/CD00171190.pdf>`_
+ (PDF); definitive resource for peripherals on the 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.
+* `STM32F103RE <http://www.st.com/internet/mcu/product/164485.jsp>`_
+ overview page with links to further references.
+
+.. rubric:: Footnotes
+
+.. [#fusedpins] See :ref:`boardUsedPins <lang-board-values-used-pins>`
+ for more information.
diff --git a/docs/source/hardware/maple-native.rst b/docs/source/hardware/maple-native.rst
new file mode 100644
index 0000000..79115fc
--- /dev/null
+++ b/docs/source/hardware/maple-native.rst
@@ -0,0 +1,6 @@
+.. _hardware-maple-native:
+
+Maple Native
+============
+
+Stub.
diff --git a/docs/source/hardware/maple-ret6.rst b/docs/source/hardware/maple-ret6.rst
new file mode 100644
index 0000000..3d2d037
--- /dev/null
+++ b/docs/source/hardware/maple-ret6.rst
@@ -0,0 +1,466 @@
+.. highlight:: sh
+
+.. _maple-ret6:
+
+Maple RET6 Edition
+==================
+
+This page is a general resource for information specific to the Maple
+RET6 Edition. The Maple RET6 Edition is a "beta" board released as a
+simple way to get a more powerful chip (the STM32F103\ **RET6**, hence
+the name) than the one on the base Maple (the STM32F103\ **RBT6**) in
+the hands of Maple developers.
+
+.. contents:: Contents
+ :local:
+
+.. TODO [dma.rst] Ref to source/dma.rst in sequel instead of libmaple-dma
+.. TODO [dac.rst] Ref to source/dac.rst in sequel instead of libmaple-dac
+.. TODO [nvic.rst] Ref to source/nvic.rst in sequel
+
+Technical Specifications
+------------------------
+
+* MCU: :ref:`STM32F103RET6 <maple-ret6-stdocs>`, a 32-bit ARM Cortex
+ M3 microprocessor
+* Clock Speed: **72 MHz**
+* **512 KB Flash** and **64 KB SRAM**
+* 43 :ref:`digital I/O pins (GPIOs) <gpio>`
+* 18 :ref:`PWM <pwm>` pins at 16 bit resolution
+* 15 :ref:`analog input (ADC) <adc>` pins at 12 bit resolution
+* Built-in, 2 channel **DAC** at 12 bit resolution (:ref:`libmaple-dac`).
+* 2 :ref:`SPI <spi>` peripherals with **I2S** support
+* 2 :ref:`I2C <i2c>` peripherals
+* 12 Channels of Direct Memory Access (**DMA**) (:ref:`libmaple-dma`)
+ with 2 DMA controllers
+* 3 :ref:`USART (serial port) <usart>` peripherals
+* 2 advanced, 4 general-purpose, and 2 basic :ref:`timers <timers>`
+* Dedicated :ref:`USB <usb>` port for programming and communications
+* :ref:`JTAG <jtag>`
+* Nested Vectored Interrupt Controller (NVIC) (including
+ :ref:`external interrupt <lang-attachinterrupt>` on GPIOs)
+* Supplies up to 500 mA at 3.3 V, with :ref:`separate 250 mA digital
+ and analog regulators <maple-ret6-adc-bank>` for low-noise analog
+ performance
+* :ref:`Open-source, four layer design <maple-ret6-hardware>`
+* Support for low power, sleep, and standby modes (<500 μA)
+* Operating Voltage: 3.3 V
+* Input Voltage (recommended): 4 V — 12 V
+* Dimensions are 2.05″ × 2.1″
+
+.. _maple-ret6-powering:
+
+Powering the Maple RET6 Edition
+-------------------------------
+
+The Maple RET6 Edition is powered in the :ref:`same way as the
+standard Maple <maple-powering>`.
+
+.. warning:: The RET6 Edition silkscreen falsely indicates that the
+ barrel jack accepts up to 18 V. We recommend a barrel jack input
+ voltage **no greater than 12V**, and potentially even lower
+ depending upon the current draw requirements of the
+ application. The same goes for powering off LiPo batteries.
+
+ Please see :ref:`Power Regulation on the Maple
+ <maple-power-regulation>` for more information.
+
+.. _maple-ret6power-regulation:
+
+Power Regulation on the Maple RET6
+----------------------------------
+
+Power regulation on the Maple RET6 works in the :ref:`same way as the
+standard Maple <maple-power-regulation>`.
+
+Using the Built-in Battery Charger
+----------------------------------
+
+The RET6 Edition has a built-in LiPo battery charger. In order to use
+it, put a jumper across the CHRG header on the power selection header
+and across the USB, or EXT selectors, depending on whether you're
+charging the battery via USB cable or barrel jack connector. The LED
+labeled CHRG will light up while the battery is being charged. When
+the battery is finished charging, the LED labeled DONE will light up.
+
+.. _maple-ret6-gpios:
+
+GPIO Information
+----------------
+
+The RET6 Edition features 38 ready-to-use general purpose input/output
+(see :ref:`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.
+
+.. _maple-ret6-but:
+
+Pin ``D38`` is the board's :ref:`button pin <lang-board-values-but>`.
+It is thus mainly useful as an :ref:`input <lang-pin-levels>`. The
+pin will :ref:`read <lang-digitalread>` ``HIGH`` when the :ref:`button
+is pressed <lang-isbuttonpressed>`.
+
+More GPIOs (numbered ``D39``\ --``D42`` on the back of the RET6
+Edition's silkscreen) are available if you use the
+:ref:`lang-disabledebugports` function; see the :ref:`board-specific
+debug pin constants <lang-board-values-debug>` for more information.
+(See :ref:`this erratum <maple-ret6-nrst-pb4>` for information about
+the pin numbered ``43`` on the silkscreen).
+
+.. TODO [0.1.0] silkscreen pictures which expand abbreviations
+
+.. _maple-ret6-pin-map-master:
+
+Master Pin Map
+^^^^^^^^^^^^^^
+
+This table shows a summary of the available functionality on every
+GPIO pin, by peripheral type. The "5 V?" column documents whether or
+not the pin is :ref:`5 volt tolerant <gpio-5v-tolerant>`.
+
+Note that this table is not exhaustive; on some pins, more peripherals
+are available than are listed here.
+
+.. csv-table::
+ :header: Pin, :ref:`GPIO <gpio>`, :ref:`ADC <adc>`, :ref:`Timer <timers>`, :ref:`I2C <i2c>`, :ref:`UART/USART <usart>`, :ref:`SPI <spi>`, 5 V?
+
+ D0, PA3, CH3, 2_CH4, -, 2_RX, -, -
+ D1, PA2, CH2, 2_CH3, -, 2_TX, -, -
+ D2, PA0, CH0, 2_CH1_ETR, -, 2_CTS, -, -
+ D3, PA1, CH1, 2_CH2, -, 2_RTS, -, -
+ D4, PB5, -, -, 1_SMBA, -, 3_MOSI, -
+ D5, PB6, -, 4_CH1, 1_SCL, -, -, Yes
+ D6, PA8, -, 1_CH1, -, 1_CK, -, Yes
+ D7, PA9, -, 1_CH2, -, 1_TX, -, Yes
+ D8, PA10, -, 1_CH3, -, 1_RX, -, Yes
+ D9, PB7, -, 4_CH2, 1_SDA, -, -, Yes
+ D10, PA4, CH4, -, -, 2_CK, 1_NSS, -
+ D11, PA7, CH7, 3_CH2, -, -, 1_MOSI, -
+ D12, PA6, CH6, 3_CH1, -, -, 1_MISO, -
+ D13, PA5, CH5, -, -, -, 1_SCK, -
+ D14, PB8, -, 4_CH3, -, -, -, Yes
+ D15, PC0, CH10, -, -, -, -, -
+ D16, PC1, CH11, -, -, -, -, -
+ D17, PC2, CH12, -, -, -, -, -
+ D18, PC3, CH13, -, -, -, -, -
+ D19, PC4, CH14, -, -, -, -, -
+ D20, PC5, CH15, -, -, -, -, -
+ D21, PC13, -, -, -, -, -, -
+ D22, PC14, -, -, -, -, -, -
+ D23, PC15, -, -, -, -, -, -
+ D24, PB9, -, 4_CH4, -, -, -, Yes
+ D25, PD2, -, 3_ETR, -, -, 5_RX, Yes
+ D26, PC10, -, -, -, -, 4_TX, Yes
+ D27, PB0, CH8, 3_CH3, -, -, -, -
+ D28, PB1, CH9, 3_CH4, -, -, -, -
+ D29, PB10, -, -, 2_SCL, 3_TX, -, Yes
+ D30, PB11, -, -, 2_SDA, 3_RX, -, Yes
+ D31, PB12, -, 1_BKIN, 2_SMBA, 3_CK, 2_NSS, Yes
+ D32, PB13, -, 1_CH1N, -, 3_CTS, 2_SCK, Yes
+ D33, PB14, -, 1_CH2N, -, 3_RTS, 2_MISO, Yes
+ D34, PB15, -, 1_CH3N, -, -, 2_MOSI, Yes
+ D35, PC6, -, 8_CH1, -, -, -, Yes
+ D36, PC7, -, 8_CH2, -, -, -, Yes
+ D37, PC8, -, 8_CH3, -, -, -, Yes
+ D38, PC9, -, 8_CH4, -, -, -, Yes
+ D39, PA13, -, -, -, -, -, Yes
+ D40, PA14, -, -, -, -, -, Yes
+ D41, PA15, -, -, -, -, 3_NSS, Yes
+ D42, PB3, -, -, -, -, 3_SCK, Yes
+
+.. _maple-ret6-gpio-port-map:
+
+GPIO Port Pin Map
+^^^^^^^^^^^^^^^^^
+
+The following table shows what pins are associated with each
+:ref:`GPIO port <gpio-ports>`.
+
+.. csv-table::
+ :header: GPIOA, GPIOB, GPIOC
+
+ PA0: D2, PB0: D27, PC0: D15
+ PA1: D3, PB1: D28, PC1: D16
+ PA2: D1, PB2: -, PC2: D17
+ PA3: D0, PB3: D42, PC3: D18
+ PA4: D10, PB4: D43, PC4: D19
+ PA5: D13, PB5: D4, PC5: D20
+ PA6: D12, PB6: D5, PC6: D35
+ PA7: D11, PB7: D9, PC7: D36
+ PA8: D6, PB8: D14, PC8: D37
+ PA9: D7, PB9: D24, PC9: D38
+ PA10: D8, PB10: D29, PC10: D26
+ PA11: -, PB11: D30, PC11: -
+ PA12: -, PB12: D31, PC12: -
+ PA13: D39, PB13: D32, PC13: D21
+ PA14: D40, PB14: D33, PC14: D22
+ PA15: D41, PB15: D34, PC15: D23
+
+.. _maple-ret6-timer-map:
+
+Timer Pin Map
+^^^^^^^^^^^^^
+
+The following table shows what pins are associated with a particular
+timer's capture/compare channels. Note that timer 5's channels share
+pins with timer 2 (e.g., timer 5 channel 1 is also available on D2,
+channel 2 on D3, etc.).
+
+.. csv-table::
+ :header: Timer, Ch. 1, Ch. 2, Ch. 3, Ch. 4
+ :delim: |
+
+ 1 | D6 | D7 | D8 | -
+ 2 | D2 | D3 | D1 | D0
+ 3 | D12 | D11 | D27 | D28
+ 4 | D5 | D9 | D14 | D24
+ 8 | D35 | D36 | D37 | :ref:`D38 <maple-ret6-but>`
+
+.. _maple-ret6-exti-map:
+
+EXTI Line Pin Map
+^^^^^^^^^^^^^^^^^
+
+The following table shows which pins connect to which :ref:`EXTI lines
+<external-interrupts-exti-line>` on the Maple RET6 Edition.
+
+.. list-table::
+ :widths: 1 1
+ :header-rows: 1
+
+ * - EXTI Line
+ - Pins
+ * - EXTI0
+ - D2, D15, D27
+ * - EXTI1
+ - D3, D16, D28
+ * - EXTI2
+ - D1, D17, D25
+ * - EXTI3
+ - D0, D18, D42
+ * - EXTI4
+ - D10, D19
+ * - EXTI5
+ - D4, D13, D20
+ * - EXTI6
+ - D5, D12, D35
+ * - EXTI7
+ - D9, D11, D36
+ * - EXTI8
+ - D6, D14, D37
+ * - EXTI9
+ - D7, D24, D38
+ * - EXTI10
+ - D8, D26, D29
+ * - EXTI11
+ - D30
+ * - EXTI12
+ - D31
+ * - EXTI13
+ - D21, D32, D39
+ * - EXTI14
+ - D22, D33, D40
+ * - EXTI15
+ - D23, D34, D41
+
+.. _maple-ret6-usart-map:
+
+USART Pin Map
+^^^^^^^^^^^^^
+
+The Maple RET6 Edition has three serial ports whose pins are broken
+out to headers (also known as :ref:`USARTs <usart>`). They communicate
+using the pins given in the following table.
+
+.. csv-table::
+ :header: Serial Port, TX, RX, CK, CTS, RTS
+ :delim: |
+
+ ``Serial1`` | D7 | D8 | D6 | |
+ ``Serial2`` | D1 | D0 | D10 | D2 | D3
+ ``Serial3`` | D29 | D30 | D31 | D32 | D33
+
+Unfortunately, :ref:`UART4 and UART5 aren't completely available
+<maple-ret6-uarts>`.
+
+.. _maple-ret6-adc-bank:
+
+Low-Noise ADC Pins
+^^^^^^^^^^^^^^^^^^
+
+The six pins at the bottom right of the board (D15—D20) generally
+offer lower-noise ADC performance than other pins on the board. If
+you’re concerned about getting good ADC readings, we recommend using
+one of these pins to take your measurements. More details in the
+:ref:`Maple hardware documentation <maple-adc-bank>`.
+
+Board-Specific Values
+---------------------
+
+This section lists the Maple RET6 Edition's :ref:`board-specific
+values <lang-board-values>`.
+
+- ``CYCLES_PER_MICROSECOND``: 72
+- ``BOARD_BUTTON_PIN``: 38
+- ``BOARD_LED_PIN``: 13
+- ``BOARD_NR_GPIO_PINS``: 44 (however, :ref:`pin D43 is not usable
+ <maple-nrst-pb4>`)
+- ``BOARD_NR_PWM_PINS``: 18
+- ``boardPWMPins``: 0, 1, 2, 3, 5, 6, 7, 8, 9, 11, 12, 14, 24, 27, 28,
+ 35, 36, 37
+- ``BOARD_NR_ADC_PINS``: 15
+- ``boardADCPins``: 0, 1, 2, 3, 10, 11, 12, 15, 16, 17, 18, 19, 20, 27, 28
+- ``BOARD_NR_USED_PINS``: 7
+- ``boardUsedPins``: ``BOARD_LED_PIN``, ``BOARD_BUTTON_PIN``,
+ ``BOARD_JTMS_SWDIO_PIN``, ``BOARD_JTCK_SWCLK_PIN``,
+ ``BOARD_JTDI_PIN``, ``BOARD_JTDO_PIN``, ``BOARD_NJTRST_PIN``
+- ``BOARD_NR_USARTS``: 3 (unfortunately, :ref:`due to the Maple Rev 5
+ design <maple-ret6-uarts>`, UARTs 4 and 5 have pins which are not
+ broken out).
+- ``BOARD_USART1_TX_PIN``: 7
+- ``BOARD_USART1_RX_PIN``: 8
+- ``BOARD_USART2_TX_PIN``: 1
+- ``BOARD_USART2_RX_PIN``: 0
+- ``BOARD_USART3_TX_PIN``: 29
+- ``BOARD_USART3_RX_PIN``: 30
+- ``BOARD_NR_SPI``: 2 (unfortunately, :ref:`due to the Maple Rev 5
+ design <maple-ret6-nrst-pb4>`, SPI3 is unavailable).
+- ``BOARD_SPI1_NSS_PIN``: 10
+- ``BOARD_SPI1_MOSI_PIN``: 11
+- ``BOARD_SPI1_MISO_PIN``: 12
+- ``BOARD_SPI1_SCK_PIN``: 13
+- ``BOARD_SPI2_NSS_PIN``: 31
+- ``BOARD_SPI2_MOSI_PIN``: 34
+- ``BOARD_SPI2_MISO_PIN``: 33
+- ``BOARD_SPI2_SCK_PIN``: 32
+- ``BOARD_JTMS_SWDIO_PIN``: 39
+- ``BOARD_JTCK_SWCLK_PIN``: 40
+- ``BOARD_JTDI_PIN``: 41
+- ``BOARD_JTDO_PIN``: 42
+- ``BOARD_NJTRST_PIN``: :ref:`43 <maple-ret6-nrst-pb4>`
+
+.. _maple-ret6-hardware:
+
+Hardware Design Files
+---------------------
+
+The hardware schematics and board layout files are available in the
+`Maple GitHub repository <https://github.com/leaflabs/maple>`_. Other
+than the processor used, the design files for the Maple RET6 edition
+are identical to the Maple Rev 5, which are in the ``maple-r5``
+subdirectory of the Maple repository. A schematic for a JTAG adapter
+suitable for use with Maple is available in the ``jtagadapter``
+directory.
+
+From the GitHub repository main page, you can download the entire
+repository by clicking the "Download" button. If you are familiar
+with `Git <http://git-scm.com/>`_, you can also clone the repository
+at the command line with ::
+
+ $ git clone git://github.com/leaflabs/maple.git
+
+.. _maple-ret6-failure-modes:
+
+Failure Modes
+-------------
+
+The following known failure modes apply to all Maple boards. The
+failure modes aren't design errors, but are easy ways to break or
+damage your board permanently.
+
+* **High voltage on non-tolerant pins**: not all header pins are 5V
+ compatible; so e.g. connecting certain serial devices in the wrong
+ way could over-voltage the pins. The :ref:`pin-mapping master table
+ <maple-ret6-pin-map-master>` details which pins are
+ :ref:`5V-tolerant <gpio-5v-tolerant>`.
+
+Errata
+------
+
+This section lists known issues and warnings for the Maple RET6
+Edition. Some of these are simply due to the RET6 Edition using the
+Maple's circuit board, which was not designed to accomodate extra
+features only available on the STM32F103RET6.
+
+.. _maple-ret6-barrel-jack:
+
+* **Barrel jack power supply voltage mistake**: The acceptable voltage
+ range given next to the barrel jack on the Maple RET6 is
+ **incorrect**. The given range is 7V — 18V. In fact, **18V is too
+ high** and should not be supplied to your board. The original
+ voltage regulators used on the Maple were rated up to 18V. However,
+ the voltage regulators on current Maple Revs are rated up to only
+ 16V, and due to the current draw requirements of the board, operate
+ properly only up to 12V. The recommended maximum voltage you should
+ apply is **12V**, and potentially even lower depending upon the
+ current draw requirements of the application. Please see :ref:`Power
+ Regulation on the Maple <maple-power-regulation>` for more
+ information.
+
+* **Power supply marketing mistake**: We originally sold the Maple
+ RET6 Edition advertising that it was capable of supplying up to 800
+ mA; the correct value is 500 mA.
+
+.. _maple-ret6-uarts:
+
+* **UART4, UART5 GPIOs unavailable**: Pins related to UARTs 4 and 5
+ are not broken out to headers (specifically, PC11/UART4_RX and
+ PC12/UART5_TX). This is due to the RET6 Edition's board layout
+ being that of the Maple Rev 5, which was not designed with these
+ RET6-specific features in mind.
+
+.. _maple-ret6-dac-ch2:
+
+* **DAC channel 2 on BOARD_LED_PIN**: The Maple Rev 5 connects PA5 to
+ the board's built-in LED; this is the same GPIO bit which is
+ connected to the DAC's channel 2 output. This is also due to the
+ RET6 Edition's board layout being that of the Maple Rev 5. The DAC
+ output channel is still available, and (if you use the
+ :ref:`standard libmaple DAC interface <libmaple-dac>`) its output is
+ buffered by default, so this may not significantly interfere with
+ its functionality.
+
+.. _maple-ret6-nrst-pb4:
+
+* **Reset and PB4 tied together**: The RET6 Edition's reset line is
+ also connected to PB4, which is labeled on the silkscreen as pin 43.
+ Thus, attempting to use pin 43 as a GPIO can reset your board. This
+ has other implications. Since PB4 is also the JTAG NJTRST line,
+ this prevents the :ref:`JTAG <jtag>` "reset halt" command from
+ working properly. Also, since PB4 is SPI3_MISO, the SPI3 peripheral
+ is not fully usable.
+
+.. _maple-ret6-sdio:
+
+* **SDIO lines not broken out**: The RET6 Edition's SDIO peripheral is
+ not usable, as some of its data lines are either not broken out or
+ used for other purposes. This is also due to the RET6 Edition's
+ board layout being that of the Maple Rev 5.
+
+.. _maple-ret6-adc-led:
+
+* **ADC on BOARD_LED_PIN**: We originally sold the Maple RET6 Edition
+ advertising 16 analog input lines. However, one of them (the one on
+ pin 13) is also connected to the built-in LED. The voltage drop
+ across the LED means that the analog to digital converter on that
+ pin is not really useful. While it is still usable, its readings
+ will be incorrect.
+
+Recommended Reading
+-------------------
+
+.. _maple-ret6-stdocs:
+
+STMicro documentation for STM32F103RE microcontroller:
+
+* `Datasheet
+ <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00191185.pdf>`_
+ (PDF); covers STM32F103xC, STM32F103xD, STM32F103xE.
+* `Reference Manual RM0008
+ <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/REFERENCE_MANUAL/CD00171190.pdf>`_
+ (PDF); definitive resource for peripherals on the 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.
+* `STM32F103RE <http://www.st.com/internet/mcu/product/164485.jsp>`_
+ overview page with links to further references.
diff --git a/docs/source/hardware/maple.rst b/docs/source/hardware/maple.rst
new file mode 100644
index 0000000..b187115
--- /dev/null
+++ b/docs/source/hardware/maple.rst
@@ -0,0 +1,618 @@
+.. highlight:: sh
+
+.. _maple:
+
+Maple
+=====
+
+This page is a general resource for information specific to the Maple.
+
+.. contents:: Contents
+ :local:
+
+.. TODO [dma.rst] Ref to dma.rst in sequel instead of libmaple-dma
+.. TODO [nvic.rst] Ref to nvic.rst in sequel
+
+Technical Specifications
+------------------------
+
+* MCU: :ref:`STM32F103RBT6 <maple-stdocs>`, a 32-bit ARM Cortex M3
+ microprocessor
+* Clock Speed: **72 MHz**
+* **128 KB Flash** and **20 KB SRAM**
+* 43 :ref:`digital I/O pins (GPIOs) <gpio>`
+* 15 :ref:`PWM <pwm>` pins at 16 bit resolution
+* 15 :ref:`analog input (ADC) <adc>` pins at 12-bit resolution
+* 2 :ref:`SPI <spi>` peripherals
+* 2 :ref:`I2C <i2c>` peripherals
+* 7 Channels of Direct Memory Access (**DMA**) (:ref:`libmaple-dma`)
+* 3 :ref:`USART (serial port) <usart>` peripherals
+* One advanced and three general-purpose :ref:`timers <timers>`
+* Dedicated :ref:`USB <usb>` port for programming and communications
+* :ref:`JTAG <jtag>`
+* Nested Vectored Interrupt Controller (NVIC) (including
+ :ref:`external interrupt <external-interrupts>` on GPIOs)
+* Supplies up to 500 mA at 3.3 V, with separate 250 mA digital and
+ analog regulators for low-noise analog performance
+* :ref:`Open source, four layer design <maple-hardware>`
+* Support for low power, sleep, and standby modes (<500 μA)
+* Operating Voltage: 3.3 V
+* Input Voltage (recommended): 4 V — 12 V
+* Dimensions: 2.05″ × 2.1″
+
+.. _maple-identify-rev:
+
+Identifying your Rev
+--------------------
+
+We went through three versions ("Revs") of the Maple hardware: Rev 1,
+Rev 3, and Rev 5 [#frev2_4]_; Rev 5, the final design, is currently on
+sale. The following sections will help you to help you identify your
+Rev.
+
+Rev 5
+^^^^^
+
+These boards went on sale in November 2010. They have white buttons
+and "r5" in small print near the "LeafLabs Maple" text next to the
+"infinity leaf" logo. The Maple Rev 5 repositioned the double header
+on the right hand side to better fit 0.1 inch pitch breadboard. This
+necessitated the removal of pins 21 and 22 from the double header;
+they are still available, but don't have any headers installed on
+them.
+
+.. figure:: /_static/img/maple_rev5.png
+ :align: center
+ :alt: Maple Rev 5
+
+Rev 3
+^^^^^
+
+This batch of boards went on sale beginning in May 2010. They have a
+darker red silkscreen and the "infinity leaf" logo. The Maple Rev 3
+was the first version which includes the built-in button, labeled BUT.
+
+.. figure:: /_static/img/maple_rev3.png
+ :align: center
+ :alt: Maple Rev 3
+
+Rev 1
+^^^^^
+
+A small number of Maple Rev 1 boards went on sale in late 2009. They
+have a light red silkscreen and a single pixelated leaf as a logo.
+
+.. figure:: /_static/img/maple_rev1.png
+ :align: center
+ :alt: Maple Rev 1
+
+.. _maple-powering:
+
+Powering the Maple
+------------------
+
+The Maple's power source is determined by the header to the left of
+the "LeafLabs" label on the silkscreen. All versions of the Maple can
+be powered from the barrel jack connector, USB, or a LiPo battery. We
+ship the Maple with a jumper on the USB selector. In order to power
+it off of an alternative source, unplug the Maple, then move the
+jumper to the desired selector before reconnecting power.
+
+You can also power the Maple via the pin labeled "Vin" on the lower
+header. This pin feeds into both the digital and analog voltage
+regulators. However, don't do this while simultaneously powering the
+board from another source, or you could damage it.
+
+When powering the board from a barrel jack, **double check the
+polarity of the barrel.** The appropriate polarity is noted on the
+silkscreen right next to the connector.
+
+.. warning:: Silkscreens on Maples up through Rev 5s manufactured in
+ Spring 2011 falsely indicated that the barrel jack could be
+ supplied by up to 18V. (Rev5s manufactured after Spring 2011 may
+ still have this error on the silk, but it has been marked over.) We
+ recommend a barrel jack input voltage **no greater than 12V**, and
+ potentially even lower depending upon the current draw requirements
+ of the application. The same goes for powering off LiPo batteries.
+
+ Please see :ref:`Power Regulation on the Maple
+ <maple-power-regulation>` for more information.
+
+.. _maple-power-regulation:
+
+Power Regulation on the Maple
+-----------------------------
+
+Power regulation on the Maple is provided by two low dropout linear
+voltage regulators. (The part is the MCP1703 from Microchip, in the
+SOT-23A package. You can download the datasheet `here
+<http://ww1.microchip.com/downloads/en/DeviceDoc/22049a.pdf>`_ ). One
+of the regulators supplies power to the digital voltage plane; the
+other supplies power to the analog voltage plane.
+
+These voltage regulators nominally take an input of up to 16V. In
+addition, while the maximum continuous output current for the board is
+250mA, if you are powering the board off higher voltages the current
+it can supply goes down, due to the regulators needing to dissipate
+the extra power. So if you are powering the board off 12V, the max
+current is about 40mA at room temperature. In general (again, at room
+temperature) the max power dissipation (PD) for the chip is about
+.37W, and output current = PD/(Vin-Vout). For exact max current
+calculations, please refer to the datasheet linked above.
+
+If you are planning to draw a lot of current from the Maple board, it
+is necessary to provide input power as close to 3.3V as
+possible. Powering the microcontroller circuitry and LEDs on the board
+alone takes approximately 30mA, so if you are powering the board with
+12V that leaves only 10mA (at best) available for powering any user
+circuitry. Attempting to draw more than 10mA runs the risk of shorting
+out the power regulators and bricking your board.
+
+Using the Built-in Battery Charger
+----------------------------------
+
+Maples Rev 3 and Rev 5 also have a built-in LiPo battery charger. In
+order to use it, put a jumper across the CHRG header on the power
+selection header and across the USB, or EXT selectors, depending on
+whether you're charging the battery via USB cable or barrel jack
+connector. The LED labeled CHRG will light up while the battery is
+being charged. When the battery is finished charging, the LED labeled
+DONE will light up.
+
+.. _maple-gpios:
+
+GPIO Information
+----------------
+
+The Maple features 38 ready-to-use general purpose input/output (see
+:ref:`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.
+
+.. _maple-ret6-but:
+
+Pin ``D38`` is the board's :ref:`button pin <lang-board-values-but>`.
+It is thus mainly useful as an :ref:`input <lang-pin-levels>`. The
+pin will :ref:`read <lang-digitalread>` ``HIGH`` when the :ref:`button
+is pressed <lang-isbuttonpressed>`.
+
+More GPIOs (numbered ``D39``\ --``D42`` on the back of the Maple's
+silkscreen) are available if you use the :ref:`lang-disabledebugports`
+function; see the :ref:`board-specific debug pin constants
+<lang-board-values-debug>` for more information. (See :ref:`this
+erratum <maple-nrst-pb4>` for information about the pin numbered
+``43`` on the silkscreen).
+
+.. TODO [0.1.0] silkscreen pictures which expand abbreviations
+
+.. _maple-pin-map-master:
+
+Master Pin Map
+^^^^^^^^^^^^^^
+
+This table shows a summary of the available functionality on every
+GPIO pin, by peripheral type. The "5 V?" column documents whether or
+not the pin is :ref:`5 volt tolerant <gpio-5v-tolerant>`.
+
+Note that this table is not exhaustive; on some pins, more peripherals
+are available than are listed here.
+
+.. csv-table::
+ :header: Pin, :ref:`GPIO <gpio>`, :ref:`ADC <adc>`, :ref:`Timer <timers>`, :ref:`I2C <i2c>`, :ref:`UART <usart>`, :ref:`SPI <spi>`, 5 V?
+
+ D0, PA3, CH3, 2_CH4, -, 2_RX, -, -
+ D1, PA2, CH2, 2_CH3, -, 2_TX, -, -
+ D2, PA0, CH0, 2_CH1_ETR, -, 2_CTS, -, -
+ D3, PA1, CH1, 2_CH2, -, 2_RTS, -, -
+ D4, PB5, -, -, 1_SMBA, -, -, -
+ D5, PB6, -, 4_CH1, 1_SCL, -, -, Yes
+ D6, PA8, -, 1_CH1, -, 1_CK, -, Yes
+ D7, PA9, -, 1_CH2, -, 1_TX, -, Yes
+ D8, PA10, -, 1_CH3, -, 1_RX, -, Yes
+ D9, PB7, -, 4_CH2, 1_SDA, -, -, Yes
+ D10, PA4, CH4, -, -, 2_CK, 1_NSS, -
+ D11, PA7, CH7, 3_CH2, -, -, 1_MOSI, -
+ D12, PA6, CH6, 3_CH1, -, -, 1_MISO, -
+ D13, PA5, CH5, -, -, -, 1_SCK, -
+ D14, PB8, -, 4_CH3, -, -, -, Yes
+ D15, PC0, CH10, -, -, -, -, -
+ D16, PC1, CH11, -, -, -, -, -
+ D17, PC2, CH12, -, -, -, -, -
+ D18, PC3, CH13, -, -, -, -, -
+ D19, PC4, CH14, -, -, -, -, -
+ D20, PC5, CH15, -, -, -, -, -
+ D21, PC13, -, -, -, -, -, -
+ D22, PC14, -, -, -, -, -, -
+ D23, PC15, -, -, -, -, -, -
+ D24, PB9, -, 4_CH4, -, -, -, Yes
+ D25, PD2, -, 3_ETR, -, -, -, Yes
+ D26, PC10, -, -, -, -, -, Yes
+ D27, PB0, CH8, 3_CH3, -, -, -, -
+ D28, PB1, CH9, 3_CH4, -, -, -, -
+ D29, PB10, -, -, 2_SCL, 3_TX, -, Yes
+ D30, PB11, -, -, 2_SDA, 3_RX, -, Yes
+ D31, PB12, -, -, 2_SMBA, 3_CK, 2_NSS, Yes
+ D32, PB13, -, -, -, 3_CTS, 2_SCK, Yes
+ D33, PB14, -, -, -, 3_RTS, 2_MISO, Yes
+ D34, PB15, -, -, -, -, 2_MOSI, Yes
+ D35, PC6, -, -, -, -, -, Yes
+ D36, PC7, -, -, -, -, -, Yes
+ D37, PC8, -, -, -, -, -, Yes
+ D38, PC9, -, -, -, -, -, Yes
+ D39, PA13, -, -, -, -, -, Yes
+ D40, PA14, -, -, -, -, -, Yes
+ D41, PA15, -, -, -, -, -, Yes
+ D42, PB3, -, -, -, -, -, Yes
+
+.. _maple-gpio-port-map:
+
+GPIO Port Pin Map
+^^^^^^^^^^^^^^^^^
+
+The following table shows what pins are associated with each
+:ref:`GPIO port <gpio-ports>`.
+
+.. csv-table::
+ :header: GPIOA, GPIOB, GPIOC
+
+ PA0: D2, PB0: D27, PC0: D15
+ PA1: D3, PB1: D28, PC1: D16
+ PA2: D1, PB2: -, PC2: D17
+ PA3: D0, PB3: D42, PC3: D18
+ PA4: D10, PB4: D43, PC4: D19
+ PA5: D13, PB5: D4, PC5: D20
+ PA6: D12, PB6: D5, PC6: D35
+ PA7: D11, PB7: D9, PC7: D36
+ PA8: D6, PB8: D14, PC8: D37
+ PA9: D7, PB9: D24, PC9: D38
+ PA10: D8, PB10: D29, PC10: D26
+ PA11: -, PB11: D30, PC11: -
+ PA12: -, PB12: D31, PC12: -
+ PA13: D39, PB13: D32, PC13: D21
+ PA14: D40, PB14: D33, PC14: D22
+ PA15: D41, PB15: D34, PC15: D23
+
+.. _maple-timer-map:
+
+Timer Pin Map
+^^^^^^^^^^^^^
+
+The following table shows what pins are associated with a particular
+timer's capture/compare channels.
+
+.. csv-table::
+ :header: Timer, Ch. 1, Ch. 2, Ch. 3, Ch. 4
+ :delim: |
+
+ 1 | D6 | D7 | D8 | -
+ 2 | D2 | D3 | D1 | D0
+ 3 | D12 | D11 | D27 | D28
+ 4 | D5 | D9 | D14 | D24
+
+.. _maple-exti-map:
+
+EXTI Line Pin Map
+^^^^^^^^^^^^^^^^^
+
+The following table shows which pins connect to which :ref:`EXTI lines
+<external-interrupts-exti-line>` on the Maple.
+
+.. list-table::
+ :widths: 1 1
+ :header-rows: 1
+
+ * - EXTI Line
+ - Pins
+ * - EXTI0
+ - D2, D15, D27
+ * - EXTI1
+ - D3, D16, D28
+ * - EXTI2
+ - D1, D17, D25
+ * - EXTI3
+ - D0, D18, D42
+ * - EXTI4
+ - D10, D19
+ * - EXTI5
+ - D4, D13, D20
+ * - EXTI6
+ - D5, D12, D35
+ * - EXTI7
+ - D9, D11, D36
+ * - EXTI8
+ - D6, D14, D37
+ * - EXTI9
+ - D7, D24, D38
+ * - EXTI10
+ - D8, D26, D29
+ * - EXTI11
+ - D30
+ * - EXTI12
+ - D31
+ * - EXTI13
+ - D21, D32, D39
+ * - EXTI14
+ - D22, D33, D40
+ * - EXTI15
+ - D23, D34, D41
+
+.. _maple-usart-map:
+
+USART Pin Map
+^^^^^^^^^^^^^
+
+The Maple has three serial ports (also known as :ref:`USARTs
+<usart>`): ``Serial1``, ``Serial2``, and ``Serial3``. They communicate
+using the pins given in the following table.
+
+.. csv-table::
+ :header: Serial Port, TX, RX, CK, CTS, RTS
+ :delim: |
+
+ ``Serial1`` | D7 | D8 | D6 | |
+ ``Serial2`` | D1 | D0 | D10 | D2 | D3
+ ``Serial3`` | D29 | D30 | D31 | D32 | D33
+
+.. _maple-adc-bank:
+
+Low-Noise ADC Pins
+^^^^^^^^^^^^^^^^^^
+
+The six pins at the bottom right of the board (D15—D20) generally
+offer lower-noise ADC performance than other pins on the board. If
+you’re concerned about getting good ADC readings, we recommend using
+one of these pins to take your measurements.
+
+Maple has an electrically isolated analog power plane with its own
+regulator, and a geometrically isolated ground plane. Pins D15—D20 are
+laid out to correspond with these analog planes, and our measurements
+indicate that they generally have the lowest noise of all the analog
+lines. However, analog performance may vary depending upon the
+activity of the other GPIOs. Consult the :ref:`Maple hardware design
+files <maple-hardware>` for more details.
+
+Board-Specific Values
+---------------------
+
+This section lists the Maple's :ref:`board-specific values
+<lang-board-values>`.
+
+- ``CYCLES_PER_MICROSECOND``: 72
+- ``BOARD_BUTTON_PIN``: 38
+- ``BOARD_LED_PIN``: 13
+- ``BOARD_NR_GPIO_PINS``: 44 (however, :ref:`pin D43 is not usable
+ <maple-nrst-pb4>`)
+- ``BOARD_NR_PWM_PINS``: 15
+- ``boardPWMPins``: 0, 1, 2, 3, 5, 6, 7, 8, 9, 11, 12, 14, 24, 27, 28
+- ``BOARD_NR_ADC_PINS``: 15
+- ``boardADCPins``: 0, 1, 2, 3, 10, 11, 12, 15, 16, 17, 18, 19, 20, 27, 28
+- ``BOARD_NR_USED_PINS``: 7
+- ``boardUsedPins``: ``BOARD_LED_PIN``, ``BOARD_BUTTON_PIN``,
+ ``BOARD_JTMS_SWDIO_PIN``, ``BOARD_JTCK_SWCLK_PIN``,
+ ``BOARD_JTDI_PIN``, ``BOARD_JTDO_PIN``, ``BOARD_NJTRST_PIN``
+- ``BOARD_NR_USARTS``: 3
+- ``BOARD_USART1_TX_PIN``: 7
+- ``BOARD_USART1_RX_PIN``: 8
+- ``BOARD_USART2_TX_PIN``: 1
+- ``BOARD_USART2_RX_PIN``: 0
+- ``BOARD_USART3_TX_PIN``: 29
+- ``BOARD_USART3_RX_PIN``: 30
+- ``BOARD_NR_SPI``: 2
+- ``BOARD_SPI1_NSS_PIN``: 10
+- ``BOARD_SPI1_MOSI_PIN``: 11
+- ``BOARD_SPI1_MISO_PIN``: 12
+- ``BOARD_SPI1_SCK_PIN``: 13
+- ``BOARD_SPI2_NSS_PIN``: 31
+- ``BOARD_SPI2_MOSI_PIN``: 34
+- ``BOARD_SPI2_MISO_PIN``: 33
+- ``BOARD_SPI2_SCK_PIN``: 32
+- ``BOARD_JTMS_SWDIO_PIN``: 39
+- ``BOARD_JTCK_SWCLK_PIN``: 40
+- ``BOARD_JTDI_PIN``: 41
+- ``BOARD_JTDO_PIN``: 42
+- ``BOARD_NJTRST_PIN``: :ref:`43 <maple-nrst-pb4>`
+
+.. _maple-hardware:
+
+Hardware Design Files
+---------------------
+
+The hardware schematics and board layout files are available in the
+`Maple GitHub repository <https://github.com/leaflabs/maple>`_. The
+design files for Rev 1, Rev 3, and Rev 5 are respectively in the
+``maple-r1``, ``maple-r3``, and ``maple-r5`` subdirectories. A
+schematic for a JTAG adapter suitable for use with Maple is available
+in the ``jtagadapter`` directory.
+
+From the GitHub repository main page, you can download the entire
+repository by clicking the "Download" button. If you are familiar
+with `Git <http://git-scm.com/>`_, you can also clone the repository
+at the command line with ::
+
+ $ git clone git://github.com/leaflabs/maple.git
+
+.. _maple-failure-modes:
+
+Failure Modes
+-------------
+
+The following are known failure modes. The failure modes aren't
+design errors, but are easy ways to break or damage your board
+permanently.
+
+* **High voltage on non-tolerant pins**: not all header pins are 5V
+ compatible; so e.g. connecting certain serial devices in the wrong
+ way could over-voltage the pins. The :ref:`pin-mapping master table
+ <maple-pin-map-master>` details which pins are :ref:`5 V tolerant
+ <gpio-5v-tolerant>`.
+
+Errata
+------
+
+This section documents design flaws and other errors.
+
+General
+^^^^^^^
+
+.. _maple-barrel-jack:
+
+* **Barrel jack power supply voltage mistake**: The acceptable voltage
+ range given next to the barrel jack on the Maple through Rev 5s
+ manufactured in Spring 2011 is **incorrect**. The given range is 7V
+ — 18V. In fact, **18V is too high** and should not be supplied to
+ your board. The original voltage regulators used on the Maple were
+ rated up to 18V. However, the voltage regulators on current Maple
+ Revs are rated up to only 16V, and due to the current draw
+ requirements of the board, operate properly only up to 12V. The
+ recommended maximum voltage you should apply is **12V**, and
+ potentially even lower depending upon the current draw requirements
+ of the application. Please see :ref:`Power Regulation on the Maple
+ <maple-power-regulation>` for more information.
+
+.. _maple-nrst-pb4:
+
+* **Reset and PB4 tied together**: The Maple's reset line is also
+ connected to PB4, which is labeled on the silkscreen as pin 43.
+ Thus, attempting to use pin 43 as a GPIO can reset your board. This
+ has other implications. Since PB4 is also the JTAG NJTRST line,
+ this prevents the :ref:`JTAG <jtag>` "reset halt" command from
+ working properly.
+
+.. _maple-power-supply:
+
+* **Power supply marketing mistake**: We originally sold the Maple
+ advertising that it was capable of supplying up to 800 mA; the
+ correct value is 500 mA.
+
+.. _maple-pwm-marketing:
+
+* **PWM marketing mistake**: We originally advertised the Maple as
+ having 22 PWM-capable pins; the correct number is 15.
+
+.. _maple-adc-marketing:
+
+* **ADC marketing mistake**: We originally advertised the Maple as
+ having 16 analog input pins. Due to :ref:`the following issue
+ <maple-adc-led>`, the correct number is 15.
+
+.. _maple-adc-led:
+
+* **ADC on BOARD_LED_PIN**: We originally sold the Maple RET6 Edition
+ advertising 16 analog input lines. However, one of them (the one on
+ pin 13) is also connected to the built-in LED. The voltage drop
+ across the LED means that the analog to digital converter on that
+ pin is not really useful. While it is still usable, its readings
+ will be incorrect.
+
+
+By Rev
+^^^^^^
+
+The following subsections lists known issues and warnings for each
+revision of the Maple board.
+
+Rev 5
+~~~~~
+
+* **Pin 3 AIN missing**: Pin 3 is capable of analog input, but on Rev
+ 5s manufactured during Fall 2010, the corresponding "AIN" is missing
+ from its silkscreen. This mistake was fixed in later manufacturing
+ runs.
+
+Rev 3
+~~~~~
+
+* **Pin 3 AIN missing**: Pin 3 is capable of analog input, but the
+ corresponding "AIN" is missing from the Rev 3 silkscreen.
+
+.. _maple-rev3-bad-buttons:
+
+* **Bad/Sticky Buttons**: a number of Rev 3 boards sold in May-June 2010
+ have questionable RESET and BUT buttons.
+
+ What seems to have happened is that the flux remover we used to
+ clean the boards before shipping eroded the plastic internals, which
+ resulted in intermittent functionality. All buttons on all shipped
+ boards did function in testing, but some may have been unreliable in
+ regular use.
+
+ If you have this problem, we will be happy to ship you new buttons
+ if you think you can re-solder them yourself, or you can ship us
+ your board and we will swap out that part.
+
+ For reference, the button part number is KMR211GLFS and the flux
+ remover we used is "Precision Electronics Cleaner" from RadioShack,
+ which is "Safe on most plastics" and contains: dipropylene glycol
+ monomethyl ether, hydrotreated heavy naphtha, dipropylene glycol
+ methyl ether acetate (say that three times fast!), and carbon
+ dioxide.
+
+* **Resistors on pins 0 and 1**: these header pins, which are RX/TX on
+ USART2 (:ref:`Serial2 <lang-serial>`), have resistors in-line
+ between the STM32 and the headers. These resistors increase the
+ impedance of the lines for ADC reads and affect the open drain GPIO
+ functionality of the pins.
+
+ These resistors were accidentally copied over from older Arduino USB
+ designs, where they appear to protect the USB-Serial converter from
+ TTL voltage on the headers.
+
+* **Silkscreen Errors**: the silkscreen on the bottom indicated PWM
+ functionality on pin 25 and listen the external header GND pin as
+ number 38 (actually 38 is connected to the BUT button). We manually
+ sharpied over both of these mistakes.
+
+Rev 1
+~~~~~
+
+* **ADC noise**: generally very high, in particular when the USB port
+ is being used for communications (including keep-alive pings when
+ connected to a computer).
+
+ This issue was resolved in Rev 3 with a 4-layer design and a
+ :ref:`geometrically isolated ADC Vref plane <maple-adc-bank>`.
+
+* **Resistors on pins 0 and 1**: these header pins, which are RX/TX on
+ USART2 (:ref:`Serial2 <lang-serial>`), have resistors in-line
+ between the STM32 and the headers. These resistors increase the
+ impedance of the lines for ADC reads and affect the open drain GPIO
+ functionality of the pins.
+
+ These resistors were accidentally copied over from older Arduino USB
+ designs, where they appear to protect the USB-Serial converter from
+ TTL voltage on the headers.
+
+* **Silkscreen Differences**: the pin numbering scheme on Rev 1 is
+ different from Rev 3, and thus Rev 3 software is difficult to use
+ with Rev 1 boards. Notably, the analog input bank is labeled A0-A4
+ on Rev 1 but 15-20 on Rev 3, and the extra header bank does not have
+ a pinout table on the bottom.
+
+* **No BUT Button**: the BUT button, useful for serial bootloading,
+ was only added in Rev 3. As a workaround, you can directly short the
+ appropriate MCU pin to Vcc; see `this forum posting
+ <http://forums.leaflabs.com/topic.php?id=32#post-126>`_.
+
+Recommended Reading
+-------------------
+
+.. _maple-stdocs:
+
+STMicro documentation for STM32F103RB microcontroller:
+
+* `Datasheet
+ <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/DATASHEET/CD00161566.pdf>`_
+ (PDF); covers STM32F103x8, STM32F103xB.
+* `Reference Manual RM0008
+ <http://www.st.com/internet/com/TECHNICAL_RESOURCES/TECHNICAL_LITERATURE/REFERENCE_MANUAL/CD00171190.pdf>`_
+ (PDF); definitive resource for peripherals on the 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.
+* `STM32F103RB <http://www.st.com/internet/mcu/product/164487.jsp>`_
+ overview page with links to further references.
+
+.. rubric:: Footnotes
+
+.. [#frev2_4] Revs 2 and 4 were prototypes that didn't pass internal
+ testing.
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