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commit d0665bcda8a4c7ca49e61615b5f1365e89d745f1
Author: Matteo Golin <matteo.go...@gmail.com>
AuthorDate: Fri May 23 19:18:46 2025 -0400
docs/avr/at90usb/micropendous3: Migrate README.txt
Migrated the README.txt files to RST format.
Signed-off-by: Matteo Golin <matteo.go...@gmail.com>
---
.../avr/at90usb/boards/micropendous3/README.txt | 546 --------------------
.../avr/at90usb/boards/micropendous3/index.rst | 573 ++++++++++++++++++++-
2 files changed, 568 insertions(+), 551 deletions(-)
diff --git
a/Documentation/platforms/avr/at90usb/boards/micropendous3/README.txt
b/Documentation/platforms/avr/at90usb/boards/micropendous3/README.txt
deleted file mode 100644
index e61f19a2c4..0000000000
--- a/Documentation/platforms/avr/at90usb/boards/micropendous3/README.txt
+++ /dev/null
@@ -1,546 +0,0 @@
-README
-^^^^^^
-
-This is the README file for the port of NuttX to the Micropendous 3 board.
-This board is develepmend by http://code.google.com/p/opendous/. The
-Micropendous 3 is based on an Atmel AT90USB646, 647, 1286 or 1287 MCU.
-NuttX was ported using the AT90USB647 version. As of this writing,
-documentation for the Micropendous board is available here:
-http://code.google.com/p/micropendous/wiki/Micropendous3
-
-Contents
-^^^^^^^^
-
- o Micropendous3 Features
- o Pin Usage
- o Atmel AVRISP mkII Connection
- o DFU Bootloader
- o Serial Console
- o Toolchains
- o Windows Native Toolchains
- o NuttX buildroot Toolchain
- o avr-libc
- o Micropendous3 Configuration Options
- o Configurations
-
-Micropendous3 Features
-^^^^^^^^^^^^^^^^^^^^^^
-
- o Based on the 64-pin USB AVR Microcontrollers: AT90USB646, AT90USB647,
- AT90USB1286, or AT90USB1287.
- o USB Full Speed (12Mbit/s)
- o USB Device Mode (Host mode supported with AT90USBxx7 devices)
- o 60kb (AT90USB64) or 120kb (AT90USB128) of available FLASH memory for
- your programs (4kb(AT90USB64)/8kb(AT90USB128) used by USB bootloader -
- stock Atmel or LUFA)
- o 4 kbytes SRAM and 2 kbytes of EEPROM (AT90USB64) or 8 kbytes SRAM and 4
- kbytes of EEPROM (AT90USB128)
- o External SRAM is possible. Layout for CY7C1019D 1-Mbit SRAM (unpopulated)
- o USB powered
- o 16MHz crystal
- o 48 General Purpose IO Pins (47 with external SRAM)
- o Vcc=VBUS jumper selects whether USB VBUS or an external supply is used
- to power the board
- o RESET and HWB buttons to enable firmware loading over USB (no external
- programmer required)
- o HWB can be used as a user button
- o USB-A Plug
- o JTAG header
- o Size LxWxH (including headers): 3.15" x 0.8" x 0.6" =~ 8cm x 2cm x 1.5cm
- o Completely OpenHardware Design
-
-Pin Usage
-^^^^^^^^^
-
- AT90USB90128/64 TQFP64
- -- ------------------------ ---------------------------------------------
- PIN SIGNAL BOARD CONNECTION
- -- ------------------------ ---------------------------------------------
- (left)
- 1 (INT.6/AIN.0) PE6 J3-25 E6, CY7C1019D ^CE (Unpopulated)
- 2 (INT.7/AIN.1/UVcon) PE7 J3-26 E7, CY7C1019D A16 (Unpopulated)
- 3 UVcc
- 4 D- USB DP
- 5 D+ USB DM
- 6 UGnd GND
- 7 UCap GND (via cap)
- 8 VBus USB VBUS
- 9 (IUID) PE3 J3-22 E3
- 10 (SS/PCINT0) PB0 J3-28 B0
- 11 (PCINT1/SCLK) PB1 J3-29 B1
- 12 (PDI/PCINT2/MOSI) PB2 J3-30 B2
- 13 (PDO/PCINT3/MISO) PB3 J3-31 B3
- 14 (PCINT4/OC.2A) PB4 J3-32 B4
- 15 (PCINT5/OC.1A) PB5 J3-33 B5
- 16 (PCINT6/OC.1B) PB6 J3-34 B6
- (bottom)
- 17 (PCINT7/OC.0A/OC.1C) PB7 J3-35 B7
- 18 (INT4/TOSC1) PE4 J3-23 E4
- 19 (INT.5/TOSC2) PE5 J3-24 E5
- 20 RESET SW1
- 21 VCC VCC
- 22 GND GND
- 23 XTAL2 X1
- 24 XTAL1 X1
- 25 (OC0B/SCL/INT0) PD0 J3-36 D0
- 26 (OC2B/SDA/INT1) PD1 J3-37 D1
- 27 (RXD1/INT2) PD2 J3-38 D2
- 28 (TXD1/INT3) PD3 J3-39 D3
- 29 (ICP1) PD4 J3-40 D4
- 30 (XCK1) PD5 J3-41 D5
- 31 (T1) PD6 J3-42 D6
- 32 (T0) PD7 J3-43 D7
- (right)
- 48 PA3 (AD3) J3-14 A3, 74AHC573 D3, CY7C1019D |O3
(Unpopulated)
- 47 PA4 (AD4) J3-15 A4, 74AHC573 D4, CY7C1019D |O4
(Unpopulated)
- 46 PA5 (AD5) J3-16 A5, 74AHC573 D5, CY7C1019D |O5
(Unpopulated)
- 45 PA6 (AD6) J3-17 A6, 74AHC573 D6, CY7C1019D |O6
(Unpopulated)
- 44 PA7 (AD7) J3-18 A7, 74AHC573 D7, CY7C1019D |O7
(Unpopulated)
- 43 PE2 (ALE/HWB) SW-2 (pulled-up), J3-21 E2, 74AHC573 Cp
- 42 PC7 (A15/IC.3/CLKO) J3-51 C7, CY7C1019D A15 (Unpopulated)
- 41 PC6 (A14/OC.3A) J3-50 C6, CY7C1019D A14 (Unpopulated)
- 40 PC5 (A13/OC.3B) J3-49 C5, CY7C1019D A13 (Unpopulated)
- 39 PC4 (A12/OC.3C) J3-48 C4, CY7C1019D A12 (Unpopulated)
- 38 PC3 (A11/T.3) J3-47 C3, CY7C1019D A11 (Unpopulated)
- 37 PC2 (A10) J3-46 C2, CY7C1019D A10 (Unpopulated)
- 36 PC1 (A9) J3-45 C1, CY7C1019D A9 (Unpopulated)
- 35 PC0 (A8) J3-44 C0, CY7C1019D A8 (Unpopulated)
- 34 PE1 (RD) J3-20 E1, CY7C1019D ^OE (Unpopulated)
- 33 PE0 (WR) J3-19 E0, CY7C1019D ^WE (Unpopulated)
- (top)
- 64 AVCC (Power circuitry)
- 63 GND GND
- 62 AREF J3-2 AREF, (Power circuitry)
- 61 PF0 (ADC0) J3-3 F0
- 60 PF1 (ADC1) J3-4 F1
- 59 PF2 (ADC2) J3-5 F2
- 58 PF3 (ADC3) J3-6 F3
- 57 PF4 (ADC4/TCK) J3-7 F4, JTAG TCK
- 56 PF5 (ADC5/TMS) J3-8 F5, JTAG TMS
- 55 PF6 (ADC6/TDO) J3-9 F6, JTAG TD0
- 54 PF7 (ADC7/TDI) J3-20 F7, JTAG TDI
- 53 GND GND
- 52 VCC VCC
- 51 PA0 (AD0) J3-11 A0, 74AHC573 D0, CY7C1019D |O0
(Unpopulated)
- 50 PA1 (AD1) J3-12 A1, 74AHC573 D1, CY7C1019D |O1
(Unpopulated)
- 49 PA2 (AD2) J3-13 A2, 74AHC573 D2, CY7C1019D |O2
(Unpopulated)
-
-Atmel AVRISP mkII Connection
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
- ISP6PIN Header
- --------------
-
- 1 2
- MISO o o VCC
- SCK o o MOSI
- RESET o o GND
-
- Micropendous 3 JTAG (JTAG10PIN Connector)
- ------------------- ---------------------
-
- 1 2 1 2
- TCK o o GND TCK o o GND
- TDO o o VCC TDO o o VTref
- TMS o o RESET TMS o o nSRST
- VCC o o N/C o o (nTRST)
- TDI o o GND TDI o o GND
-
- JTAGICE mkII Connection to 10-pin Header
- ------------------------------------------
- 10PIN Header 6PIN Header
- -------------------- ---------------------
- Pin 1 TCK Pin 3 SCK
- Pin 2 GND Pin 6 GND
- Pin 3 TDO Pin 1 MISO
- Pin 4 VTref Pin 2 Vcc
- Pin 6 nSRT Pin 5 Reset
- Pin 9 TDI Pin 4 MOSI
-
-DFU Bootloader
-^^^^^^^^^^^^^^
-
-There is also an DFU bootloader that resides in the upper 8Kb of FLASH
-(unless you ERASE the flash with ICE). You can enter this bootloader
-(if it is in FLASH) by:
-
-Holding both the SW1 (RESET) and SW2, then releasing SW1 while continuing
-to hold SW2. SW2 connects to the PE2/HWB signal and causes a reset into
-the bootloader memory region.
-
-Then you can use FLIP to load code into FLASH (available at the Atmel Web
-Site). The DFU USB driver for the DFU bootload is available in the usb
-subdirectory in the FLIP installation location.
-
-Serial Console
-^^^^^^^^^^^^^^
-
- A serial console is supported on an external MAX232/MAX3232 Connected
- on PD2 and PD3:
-
- Port D, Bit 2: RXD1, Receive Data (Data input pin for the USART1). When
- the USART1 receiver is enabled this pin is configured as an input
- regardless of the value of DDD2. When the USART forces this pin to
- be an input, the pull-up can still be controlled by the PORTD2 bit.
- Port D, Bit 3: TXD1, Transmit Data (Data output pin for the USART1).
- When the USART1 Transmitter is enabled, this pin is configured as
- an output regardless of the value of DDD3.
-
- AT90USB90128/64 TQFP64
- -- ------------------------ ---------------------------------------------
- PIN SIGNAL BOARD CONNECTION
- -- ------------------------ ---------------------------------------------
- 27 (RXD1/INT2) PD2 J3-38 D2
- 28 (TXD1/INT3) PD3 J3-39 D3
-
-Toolchains
-^^^^^^^^^^
-
-There are several toolchain options. However, testing has been performed
-using *only* the NuttX buildroot toolchain described below. Therefore,
-the NuttX buildroot toolchain is the recommended choice.
-
-The toolchain may be selected using the kconfig-mconf tool (via 'make
menuconfig'),
-by editing the existing configuration file (defconfig), or by overriding
-the toolchain on the make commandline with CONFIG_AVR_TOOLCHAIN=<toolchain>.
-
-The valid values for <toolchain> are BUILDROOT, CROSSPACK, LINUXGCC and WINAVR.
-
-Buildroot:
-
- There is a DIY buildroot version for the AVR boards here:
- http://bitbucket.org/nuttx/buildroot/downloads/. See the
- following section for details on building this toolchain.
-
- Before building, make sure that the path to the new toolchain is included
- in your PATH environment variable.
-
- After configuring NuttX, make sure that CONFIG_AVR_BUILDROOT_TOOLCHAIN=y is
set in your
- .config file.
-
-WinAVR:
-
- For Cygwin development environment on Windows machines, you can use
- WinAVR: http://sourceforge.net/projects/winavr/files/
-
- Before building, make sure that the path to the new toolchain is included
- in your PATH environment variable.
-
- After configuring NuttX, make sure that CONFIG_AVR_WINAVR_TOOLCHAIN=y is set
in your
- .config file.
-
- WARNING: There is an incompatible version of cygwin.dll in the WinAVR/bin
- directory! Make sure that the path to the correct cygwin.dll file precedes
- the path to the WinAVR binaries!
-
-Linux:
-
- For Linux, there are widely available avr-gcc packages. On Ubuntu, use:
- sudo apt-get install gcc-avr gdb-avr avr-libc
-
- After configuring NuttX, make sure that CONFIG_AVR_LINUXGCC_TOOLCHAIN=y is
set in your
- .config file.
-
-macOS:
-
- For macOS, the CrossPack for AVR toolchain is available from:
-
- http://www.obdev.at/products/crosspack/index.html
-
- This toolchain is functionally equivalent to the Linux GCC toolchain.
-
-Windows Native Toolchains
-^^^^^^^^^^^^^^^^^^^^^^^^^
-
- The WinAVR toolchain is a Windows native toolchain. There are several
- limitations to using a Windows native toolchain in a Cygwin environment.
- The three biggest are:
-
- 1. The Windows toolchain cannot follow Cygwin paths. Path conversions are
- performed automatically in the Cygwin makefiles using the 'cygpath'
- utility but you might easily find some new path problems. If so, check
- out 'cygpath -w'
-
- 2. Windows toolchains cannot follow Cygwin symbolic links. Many symbolic
- links are used in NuttX (e.g., include/arch). The make system works
- around these problems for the Windows tools by copying directories
- instead of linking them. But this can also cause some confusion for
- you: For example, you may edit a file in a "linked" directory and find
- that your changes had no effect. That is because you are building the
- copy of the file in the "fake" symbolic directory. If you use a
- Windows toolchain, you should get in the habit of making like this:
-
- make clean_context all
-
- An alias in your .bashrc file might make that less painful.
-
- An additional issue with the WinAVR toolchain, in particular, is that it
- contains an incompatible version of the Cygwin DLL in its bin/ directory.
- You must take care that the correct Cygwin DLL is used.
-
-NuttX buildroot Toolchain
-^^^^^^^^^^^^^^^^^^^^^^^^^
-
- If NuttX buildroot toolchain source tarball cne can be downloaded from the
- NuttX Bitbucket download site (https://bitbucket.org/nuttx/nuttx/downloads/).
- This GNU toolchain builds and executes in the Linux or Cygwin environment.
-
- 1. You must have already configured NuttX in <some-dir>/nuttx.
-
- tools/configure.sh micropendous3:<sub-dir>
-
- NOTE: you also must copy avr-libc header files into the NuttX include
- directory with command perhaps like:
-
- cp -a /cygdrive/c/WinAVR/include/avr include/.
-
- 2. Download the latest buildroot package into <some-dir>
-
- 3. unpack the buildroot tarball. The resulting directory may
- have versioning information on it like buildroot-x.y.z. If so,
- rename <some-dir>/buildroot-x.y.z to <some-dir>/buildroot.
-
- 4. cd <some-dir>/buildroot
-
- 5. cp boards/avr-defconfig-4.5.2 .config
-
- 6. make oldconfig
-
- 7. make
-
- 8. Make sure that the PATH variable includes the path to the newly built
- binaries.
-
- See the file boards/README.txt in the buildroot source tree. That has more
- detailed PLUS some special instructions that you will need to follow if you
- are building a toolchain for Cygwin under Windows.
-
-avr-libc
-^^^^^^^^
-
-Header Files
-
- In any case, header files from avr-libc are required:
http://www.nongnu.org/avr-libc/.
- A snapshot of avr-lib is included in the WinAVR installation. For Linux
- development platforms, avr-libc package is readily available (and would
- be installed in the apt-get command shown above). But if you are using
- the NuttX buildroot configuration on Cygwin, then you will have to build
- get avr-libc from binaries.
-
-Header File Installation
-
- The NuttX build will required that the AVR header files be available via
- the NuttX include directory. This can be accomplished by either copying
- the avr-libc header files into the NuttX include directory:
-
- cp -a <avr-libc-path>/include/avr <nuttx-path>/include/.
-
- Or simply using a symbolic link:
-
- ln -s <avr-libc-path>/include/avr <nuttx-path>/include/.
-
-Build Notes:
-
- It may not be necessary to have a built version of avr-lib; only header files
- are required. But if you choose to use the optimized library functions of
- the floating point library, then you may have to build avr-lib from sources.
- Below are instructions for building avr-lib from fresh sources:
-
- 1. Download the avr-libc package from:
-
- http://savannah.nongnu.org/projects/avr-libc/
-
- I am using avr-lib-1.7.1.tar.bz2
-
- 2. Unpack the tarball and cd into the
-
- tar jxf avr-lib-1.7.1.tar.bz2
- cd avr-lib-1.7.1
-
- 3. Configure avr-lib. Assuming that WinAVR is installed at the following
- location:
-
- export PATH=/cygdrive/c/WinAVR/bin:$PATH
- ./configure --build=`./config.guess` --host=avr
-
- This takes a *long* time.
-
- 4. Make avr-lib.
-
- make
-
- This also takes a long time because it generates variants for nearly
- all AVR chips.
-
- 5. Install avr-lib.
-
- make install
-
-Micropendous3 Configuration Options
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
- CONFIG_ARCH - Identifies the arch/ subdirectory. This should
- be set to:
-
- CONFIG_ARCH=avr
-
- CONFIG_ARCH_family - For use in C code:
-
- CONFIG_ARCH_AVR=y
-
- CONFIG_ARCH_architecture - For use in C code:
-
- CONFIG_ARCH_CHIP_AT90USB=y
-
- CONFIG_ARCH_CHIP - Identifies the arch/*/chip subdirectory
-
- CONFIG_ARCH_CHIP=at90usb
-
- CONFIG_ARCH_CHIP_name - For use in C code to identify the exact
- chip. This should be exactly one of
-
- CONFIG_ARCH_CHIP_AT90USB646=y
- CONFIG_ARCH_CHIP_AT90USB647=y
- CONFIG_ARCH_CHIP_AT90USB1286=y
- CONFIG_ARCH_CHIP_AT90USB1287=y
-
- Depending on which Micropendous3 version you have.
-
- CONFIG_ARCH_BOARD - Identifies the boards/ subdirectory and
- hence, the board that supports the particular chip or SoC.
-
- CONFIG_ARCH_BOARD=micropendous3
-
- CONFIG_ARCH_BOARD_name - For use in C code
-
- CONFIG_ARCH_BOARD_MICROPENOUS3=y
-
- CONFIG_ARCH_LOOPSPERMSEC - Must be calibrated for correct operation
- of delay loops
-
- CONFIG_ENDIAN_BIG - define if big endian (default is little
- endian)
-
- CONFIG_RAM_SIZE - Describes the installed DRAM. One of:
-
- CONFIG_RAM_SIZE=(4*1024) - (4Kb)
- CONFIG_RAM_SIZE=(8*1024) - (8Kb)
-
- CONFIG_RAM_START - The start address of installed SRAM
-
- CONFIG_RAM_START=0x800100
-
- CONFIG_ARCH_LEDS - Use LEDs to show state. Unique to boards that
- have LEDs
-
- CONFIG_ARCH_INTERRUPTSTACK - This architecture supports an interrupt
- stack. If defined, this symbol is the size of the interrupt
- stack in bytes. If not defined, the user task stacks will be
- used during interrupt handling.
-
- CONFIG_ARCH_STACKDUMP - Do stack dumps after assertions
-
- CONFIG_ARCH_LEDS - Use LEDs to show state. Unique to board architecture.
-
- Individual subsystems can be enabled:
-
- CONFIG_AVR_INT0=n
- CONFIG_AVR_INT1=n
- CONFIG_AVR_INT2=n
- CONFIG_AVR_INT3=n
- CONFIG_AVR_INT4=n
- CONFIG_AVR_INT5=n
- CONFIG_AVR_INT6=n
- CONFIG_AVR_INT7=n
- CONFIG_AVR_USBHOST=n
- CONFIG_AVR_USBDEV=n
- CONFIG_AVR_WDT=n
- CONFIG_AVR_TIMER0=n
- CONFIG_AVR_TIMER1=n
- CONFIG_AVR_TIMER2=n
- CONFIG_AVR_TIMER3=n
- CONFIG_AVR_SPI=n
- CONFIG_AVR_USART1=y
- CONFIG_AVR_ANACOMP=n
- CONFIG_AVR_ADC=n
- CONFIG_AVR_TWI=n
-
- If the watchdog is enabled, this specifies the initial timeout. Default
- is maximum supported value.
-
- CONFIG_WDTO_15MS
- CONFIG_WDTO_30MS
- CONFIG_WDTO_60MS
- CONFIG_WDTO_120MS
- CONFIG_WDTO_1250MS
- CONFIG_WDTO_500MS
- CONFIG_WDTO_1S
- CONFIG_WDTO_2S
- CONFIG_WDTO_4S
- CONFIG_WDTO_8S
-
- AT90USB specific device driver settings
-
- CONFIG_USARTn_SERIAL_CONSOLE - selects the USARTn for the
- console and ttys0 (default is no serial console).
- CONFIG_USARTn_RXBUFSIZE - Characters are buffered as received.
- This specific the size of the receive buffer
- CONFIG_USARTn_TXBUFSIZE - Characters are buffered before
- being sent. This specific the size of the transmit buffer
- CONFIG_USARTn_BAUD - The configure BAUD of the USART. Must be
- CONFIG_USARTn_BITS - The number of bits. Must be either 7 or 8.
- CONFIG_USARTn_PARTIY - 0=no parity, 1=odd parity, 2=even parity
- CONFIG_USARTn_2STOP - Two stop bits
-
-Configurations
-^^^^^^^^^^^^^^
-
-Common Configuration Notes
---------------------------
-
- 1. Each Micropendous3 configuration is maintained in a sub-directory and
- can be selected as follow:
-
- tools/configure.sh micropendous3:<subdir>
-
- Where <subdir> is one of the configuration sub-directories described in
- the following paragraph.
-
- NOTE: You must also copy avr-libc header files, perhaps like:
-
- cp -a /cygdrive/c/WinAVR/include/avr include/.
-
- 2. These configurations use the mconf-based configuration tool. To
- change a configurations using that tool, you should:
-
- a. Build and install the kconfig-mconf tool. See nuttx/README.txt
- see additional README.txt files in the NuttX tools repository.
-
- b. Execute 'make menuconfig' in nuttx/ in order to start the
- reconfiguration process.
-
- 3. By default, all configurations assume the NuttX Buildroot toolchain
- under Cygwin with Windows. This is easily reconfigured:
-
- CONFIG_HOST_WINDOWS=y
- CONFIG_WINDOWS_CYGWIN=y
- CONFIG_AVR_BUILDROOT_TOOLCHAIN=y
-
- 4. Build with GCC disables CONFIG_DEBUG_OPT_UNUSED_SECTIONS by default.
- This is because the linker script was not checked to determine
- if it properly prevents removal of sections which the linker considers
- unreferenced but which must be present in the binary.
-
-Configuration Sub-Directories
------------------------------
-
- hello:
- The simple apps/examples/hello "Hello, World!" example.
-
- FLASH/SRAM Requirements (as of 6/16/2011):
-
- $ avr-nuttx-elf-size nuttx
- text data bss dec hex filename
- 24816 978 308 26102 65f6 nuttx
-
- Strings are in SRAM.
diff --git a/Documentation/platforms/avr/at90usb/boards/micropendous3/index.rst
b/Documentation/platforms/avr/at90usb/boards/micropendous3/index.rst
index 18742ba3cb..b99446d4d8 100644
--- a/Documentation/platforms/avr/at90usb/boards/micropendous3/index.rst
+++ b/Documentation/platforms/avr/at90usb/boards/micropendous3/index.rst
@@ -1,6 +1,569 @@
-=============
-micropendous3
-=============
+==============
+Micropendous 3
+==============
-.. include:: README.txt
- :literal:
+.. tags:: arch:avr, chip:at90usb
+
+This is the documentation page for the port of NuttX to the Micropendous 3
+board. This board is developed by `opendous
+<http://code.google.com/p/opendous/>`_. The Micropendous 3 is based on an Atmel
+AT90USB646, 647, 1286 or 1287 MCU. NuttX was ported using the AT90USB647
+version. As of this writing, documentation for the Micropendous board is
+available `here <http://code.google.com/p/micropendous/wiki/Micropendous3>`_
+
+Micropendous3 Features
+======================
+
+* Based on the 64-pin USB AVR Microcontrollers: AT90USB646, AT90USB647,
+* AT90USB1286, or AT90USB1287.
+* USB Full Speed (12Mbit/s)
+* USB Device Mode (Host mode supported with AT90USBxx7 devices)
+* 60kb (AT90USB64) or 120kb (AT90USB128) of available FLASH memory for
+* your programs (4kb(AT90USB64)/8kb(AT90USB128) used by USB bootloader -
+* stock Atmel or LUFA)
+* 4 kbytes SRAM and 2 kbytes of EEPROM (AT90USB64) or 8 kbytes SRAM and 4
+* kbytes of EEPROM (AT90USB128)
+* External SRAM is possible. Layout for CY7C1019D 1-Mbit SRAM (unpopulated)
+* USB powered
+* 16MHz crystal
+* 48 General Purpose IO Pins (47 with external SRAM)
+* Vcc=VBUS jumper selects whether USB VBUS or an external supply is used
+* to power the board
+* RESET and HWB buttons to enable firmware loading over USB (no external
+* programmer required)
+* HWB can be used as a user button
+* USB-A Plug
+* JTAG header
+* Size LxWxH (including headers): 3.15" x 0.8" x 0.6" =~ 8cm x 2cm x 1.5cm
+* Completely OpenHardware Design
+
+Pin Usage
+=========
+
+AT90USB90128/64 TQFP64
+
+=== ======================== =============================================
+PIN SIGNAL BOARD CONNECTION
+=== ======================== =============================================
+1 (INT.6/AIN.0) PE6 J3-25 E6, CY7C1019D ^CE (Unpopulated)
+2 (INT.7/AIN.1/UVcon) PE7 J3-26 E7, CY7C1019D A16 (Unpopulated)
+3 UVcc
+4 D- USB DP
+5 D+ USB DM
+6 UGnd GND
+7 UCap GND (via cap)
+8 VBus USB VBUS
+9 (IUID) PE3 J3-22 E3
+10 (SS/PCINT0) PB0 J3-28 B0
+11 (PCINT1/SCLK) PB1 J3-29 B1
+12 (PDI/PCINT2/MOSI) PB2 J3-30 B2
+13 (PDO/PCINT3/MISO) PB3 J3-31 B3
+14 (PCINT4/OC.2A) PB4 J3-32 B4
+15 (PCINT5/OC.1A) PB5 J3-33 B5
+16 (PCINT6/OC.1B) PB6 J3-34 B6
+17 (PCINT7/OC.0A/OC.1C) PB7 J3-35 B7
+18 (INT4/TOSC1) PE4 J3-23 E4
+19 (INT.5/TOSC2) PE5 J3-24 E5
+20 RESET SW1
+21 VCC VCC
+22 GND GND
+23 XTAL2 X1
+24 XTAL1 X1
+25 (OC0B/SCL/INT0) PD0 J3-36 D0
+26 (OC2B/SDA/INT1) PD1 J3-37 D1
+27 (RXD1/INT2) PD2 J3-38 D2
+28 (TXD1/INT3) PD3 J3-39 D3
+29 (ICP1) PD4 J3-40 D4
+30 (XCK1) PD5 J3-41 D5
+31 (T1) PD6 J3-42 D6
+32 (T0) PD7 J3-43 D7
+48 PA3 (AD3) J3-14 A3, 74AHC573 D3, CY7C1019D O3 (Unpopulated)
+47 PA4 (AD4) J3-15 A4, 74AHC573 D4, CY7C1019D O4 (Unpopulated)
+46 PA5 (AD5) J3-16 A5, 74AHC573 D5, CY7C1019D O5 (Unpopulated)
+45 PA6 (AD6) J3-17 A6, 74AHC573 D6, CY7C1019D O6 (Unpopulated)
+44 PA7 (AD7) J3-18 A7, 74AHC573 D7, CY7C1019D O7 (Unpopulated)
+43 PE2 (ALE/HWB) SW-2 (pulled-up), J3-21 E2, 74AHC573 Cp
+42 PC7 (A15/IC.3/CLKO) J3-51 C7, CY7C1019D A15 (Unpopulated)
+41 PC6 (A14/OC.3A) J3-50 C6, CY7C1019D A14 (Unpopulated)
+40 PC5 (A13/OC.3B) J3-49 C5, CY7C1019D A13 (Unpopulated)
+39 PC4 (A12/OC.3C) J3-48 C4, CY7C1019D A12 (Unpopulated)
+38 PC3 (A11/T.3) J3-47 C3, CY7C1019D A11 (Unpopulated)
+37 PC2 (A10) J3-46 C2, CY7C1019D A10 (Unpopulated)
+36 PC1 (A9) J3-45 C1, CY7C1019D A9 (Unpopulated)
+35 PC0 (A8) J3-44 C0, CY7C1019D A8 (Unpopulated)
+34 PE1 (RD) J3-20 E1, CY7C1019D ^OE (Unpopulated)
+33 PE0 (WR) J3-19 E0, CY7C1019D ^WE (Unpopulated)
+64 AVCC (Power circuitry)
+63 GND GND
+62 AREF J3-2 AREF, (Power circuitry)
+61 PF0 (ADC0) J3-3 F0
+60 PF1 (ADC1) J3-4 F1
+59 PF2 (ADC2) J3-5 F2
+58 PF3 (ADC3) J3-6 F3
+57 PF4 (ADC4/TCK) J3-7 F4, JTAG TCK
+56 PF5 (ADC5/TMS) J3-8 F5, JTAG TMS
+55 PF6 (ADC6/TDO) J3-9 F6, JTAG TD0
+54 PF7 (ADC7/TDI) J3-20 F7, JTAG TDI
+53 GND GND
+52 VCC VCC
+51 PA0 (AD0) J3-11 A0, 74AHC573 D0, CY7C1019D O0 (Unpopulated)
+50 PA1 (AD1) J3-12 A1, 74AHC573 D1, CY7C1019D O1 (Unpopulated)
+49 PA2 (AD2) J3-13 A2, 74AHC573 D2, CY7C1019D O2 (Unpopulated)
+=== ======================== =============================================
+
+Atmel AVRISP mkII Connection
+============================
+
+ISP6PIN Header
+
+.. code:: text
+
+ 1 2
+ MISO o o VCC
+ SCK o o MOSI
+ RESET o o GND
+
+Micropendous 3 JTAG (JTAG10PIN Connector)
+
+.. code:: text
+
+ 1 2 1 2
+ TCK o o GND TCK o o GND
+ TDO o o VCC TDO o o VTref
+ TMS o o RESET TMS o o nSRST
+ VCC o o N/C o o (nTRST)
+ TDI o o GND TDI o o GND
+
+JTAGICE mkII Connection to 10-pin Header
+
+==================== =====================
+10PIN Header 6PIN Header
+==================== =====================
+Pin 1 TCK Pin 3 SCK
+Pin 2 GND Pin 6 GND
+Pin 3 TDO Pin 1 MISO
+Pin 4 VTref Pin 2 Vcc
+Pin 6 nSRT Pin 5 Reset
+Pin 9 TDI Pin 4 MOSI
+==================== =====================
+
+DFU Bootloader
+==============
+
+There is also an DFU bootloader that resides in the upper 8Kb of FLASH (unless
+you ERASE the flash with ICE). You can enter this bootloader (if it is in
FLASH)
+by:
+
+Holding both the SW1 (RESET) and SW2, then releasing SW1 while continuing to
+hold SW2. SW2 connects to the PE2/HWB signal and causes a reset into the
+bootloader memory region.
+
+Then you can use FLIP to load code into FLASH (available at the Atmel Web
Site).
+The DFU USB driver for the DFU bootload is available in the usb subdirectory in
+the FLIP installation location.
+
+Serial Console
+==============
+
+A serial console is supported on an external MAX232/MAX3232 Connected on PD2
and
+PD3:
+
+**Port D, Bit 2: RXD1, Receive Data (Data input pin for the USART1).**
+
+When the USART1 receiver is enabled this pin is configured as an input
+regardless of the value of DDD2. When the USART forces this pin to be an input,
+the pull-up can still be controlled by the PORTD2 bit.
+
+**Port D, Bit 3: TXD1, Transmit Data (Data output pin for the USART1).**
+
+When the USART1 Transmitter is enabled, this pin is configured as an output
+regardless of the value of DDD3.
+
+AT90USB90128/64 TQFP64
+
+=== ======================= =============================================
+PIN SIGNAL BOARD CONNECTION
+=== ======================= =============================================
+27 (RXD1/INT2) PD2 J3-38 D2
+28 (TXD1/INT3) PD3 J3-39 D3
+=== ======================= =============================================
+
+Toolchains
+==========
+
+There are several toolchain options. However, testing has been performed using
+*only* the NuttX buildroot toolchain described below. Therefore, the NuttX
+buildroot toolchain is the recommended choice.
+
+The toolchain may be selected using the kconfig-mconf tool (via ``make
+menuconfig``), by editing the existing configuration file (``defconfig``), or
by
+overriding the toolchain on the make commandline with
+``CONFIG_AVR_TOOLCHAIN=<toolchain>``.
+
+The valid values for ``<toolchain>`` are ``BUILDROOT``, ``CROSSPACK``,
+``LINUXGCC`` and ``WINAVR``.
+
+Buildroot
+---------
+
+There is a DIY buildroot version for the AVR boards here:
+http://bitbucket.org/nuttx/buildroot/downloads/. See the following section for
+details on building this toolchain.
+
+Before building, make sure that the path to the new toolchain is included in
+your ``PATH`` environment variable.
+
+After configuring NuttX, make sure that ``CONFIG_AVR_BUILDROOT_TOOLCHAIN=y`` is
+set in your ``.config`` file.
+
+WinAVR
+------
+
+For Cygwin development environment on Windows machines, you can use WinAVR:
+http://sourceforge.net/projects/winavr/files/
+
+Before building, make sure that the path to the new toolchain is included in
+your ``PATH`` environment variable.
+
+After configuring NuttX, make sure that ``CONFIG_AVR_WINAVR_TOOLCHAIN=y`` is
set
+in your ``.config`` file.
+
+.. warning::
+
+ There is an incompatible version of ``cygwin.dll`` in the ``WinAVR/bin``
+ directory! Make sure that the path to the correct ``cygwin.dll`` file
+ precedes the path to the WinAVR binaries!
+
+Linux
+-----
+
+For Linux, there are widely available avr-gcc packages. On Ubuntu, use:
+sudo apt-get install gcc-avr gdb-avr avr-libc
+
+After configuring NuttX, make sure that CONFIG_AVR_LINUXGCC_TOOLCHAIN=y is set
in your
+.config file.
+
+macOS
+-----
+
+For macOS, the CrossPack for AVR toolchain is available from:
+http://www.obdev.at/products/crosspack/index.html
+
+This toolchain is functionally equivalent to the Linux GCC toolchain.
+
+Windows Native Toolchains
+=========================
+
+The WinAVR toolchain is a Windows native toolchain. There are several
+limitations to using a Windows native toolchain in a Cygwin environment. The
+three biggest are:
+
+1. The Windows toolchain cannot follow Cygwin paths. Path conversions are
+ performed automatically in the Cygwin makefiles using the ``cygpath``
utility
+ but you might easily find some new path problems. If so, check out
``cygpath
+ -w``
+
+2. Windows toolchains cannot follow Cygwin symbolic links. Many symbolic links
+ are used in NuttX (e.g., ``include/arch``). The make system works around
+ these problems for the Windows tools by copying directories instead of
+ linking them. But this can also cause some confusion for you: For example,
+ you may edit a file in a "linked" directory and find that your changes had
no
+ effect. That is because you are building the copy of the file in the "fake"
+ symbolic directory. If you use a Windows toolchain, you should get in the
+ habit of making like this:
+
+ .. code:: console
+
+ $ make clean_context all
+
+ An alias in your ``.bashrc`` file might make that less painful.
+
+An additional issue with the WinAVR toolchain, in particular, is that it
+contains an incompatible version of the Cygwin DLL in its ``bin/`` directory.
+You must take care that the correct Cygwin DLL is used.
+
+NuttX buildroot toolchain
+=========================
+
+If NuttX buildroot toolchain source tarball cne can be downloaded from the
NuttX
+Bitbucket download site (https://bitbucket.org/nuttx/nuttx/downloads/). This
GNU
+toolchain builds and executes in the Linux or Cygwin environment.
+
+1. You must have already configured NuttX in ``<some-dir>/nuttx``.
+
+ .. code:: console
+
+ $ tools/configure.sh micropendous3:<sub-dir>
+
+ .. note::
+
+ You also must copy avr-libc header files into the NuttX include directory
+ with a command perhaps like:
+
+ .. code:: console
+
+ $ cp -a /cygdrive/c/WinAVR/include/avr include/.
+
+2. Download the latest buildroot package into ``<some-dir>``
+
+3. Unpack the buildroot tarball. The resulting directory may have versioning
+ information on it like ``buildroot-x.y.z``. If so, rename
+ ``<some-dir>/buildroot-x.y.z`` to ``<some-dir>/buildroot``.
+
+ .. code:: console
+
+ $ cd <some-dir>/buildroot
+ $ cp boards/avr-defconfig-4.5.2 .config
+ $ make oldconfig
+ $ make
+
+4. Make sure that the ``PATH`` variable includes the path to the newly built
+ binaries.
+
+See the file ``boards/README.txt`` in the buildroot source tree.That has more
+detailed PLUS some special instructions that you will need to follow if you are
+building a toolchain for Cygwin under Windows.
+
+avr-libc
+========
+
+Header Files
+------------
+
+In any case, header files from avr-libc are required:
+http://www.nongnu.org/avr-libc/. A snapshot of avr-lib is included in the
WinAVR
+installation. For Linux development platforms, avr-libc package is readily
+available (and would be installed in the apt-get command shown above). But if
+you are using the NuttX buildroot configuration on Cygwin, then you will have
to
+build get avr-libc from binaries.
+
+Header File Installation
+------------------------
+
+The NuttX build will required that the AVR header files be available via the
+NuttX include directory. This can be accomplished by either copying the
+avr-libc header files into the NuttX include directory:
+
+.. code:: console
+
+ $ cp -a <avr-libc-path>/include/avr <nuttx-path>/include/.
+
+Or simply using a symbolic link:
+
+.. code:: console
+
+ $ ln -s <avr-libc-path>/include/avr <nuttx-path>/include/.
+
+Build Notes
+-----------
+
+It may not be necessary to have a built version of avr-lib; only header files
+are required. But if you choose to use the optimized library functions of the
+floating point library, then you may have to build avr-lib from sources. Below
+are instructions for building avr-lib from fresh sources:
+
+1. Download the avr-libc package from
+ http://savannah.nongnu.org/projects/avr-libc/. I am using
+ avr-lib-1.7.1.tar.bz2
+
+2. Unpack the tarball and ``cd`` into it:
+
+ .. code:: console
+
+ $ tar jxf avr-lib-1.7.1.tar.bz2
+ $ cd avr-lib-1.7.1
+
+3. Configure avr-lib. Assuming that WinAVR is installed at the following
+ location:
+
+ .. code:: console
+
+ $ export PATH=/cygdrive/c/WinAVR/bin:$PATH
+ $ ./configure --build=`./config.guess` --host=avr
+
+ This takes a *long* time.
+
+4. Make avr-lib.
+
+ .. code:: console
+
+ $ make
+
+ This also takes a long time because it generates variants for nearly
+ all AVR chips.
+
+5. Install avr-lib.
+
+ .. code:: console
+
+ $ make install
+
+Micropendous 3 Configuration Options
+====================================
+
+* ``CONFIG_ARCH``: Identifies the ``arch/`` subdirectory. This should be set
+ to:
+
+ * ``CONFIG_ARCH=avr``
+
+* ``CONFIG_ARCH_family``: For use in C code:
+
+ * ``CONFIG_ARCH_AVR=y``
+
+* ``CONFIG_ARCH_architecture``: For use in C code:
+
+ * ``CONFIG_ARCH_CHIP_AT90USB=y``
+
+* ``CONFIG_ARCH_CHIP``: Identifies the ``arch/*/chip`` subdirectory
+
+ * ``CONFIG_ARCH_CHIP=at90usb``
+
+* ``CONFIG_ARCH_CHIP_name``: For use in C code to identify the exact chip. This
+ should be exactly one of:
+
+ * ``CONFIG_ARCH_CHIP_AT90USB646=y``
+ * ``CONFIG_ARCH_CHIP_AT90USB647=y``
+ * ``CONFIG_ARCH_CHIP_AT90USB1286=y``
+ * ``CONFIG_ARCH_CHIP_AT90USB1287=y``
+
+ Depending on which Micropendous3 version you have.
+
+* ``CONFIG_ARCH_BOARD``: Identifies the ``boards/`` subdirectory and hence, the
+ board that supports the particular chip or SoC.
+
+ * ``CONFIG_ARCH_BOARD=micropendous3``
+
+* ``CONFIG_ARCH_BOARD_name``: For use in C code
+
+ * ``CONFIG_ARCH_BOARD_MICROPENOUS3=y``
+
+* ``CONFIG_ARCH_LOOPSPERMSEC``: Must be calibrated for correct operation of
+ delay loops
+
+* ``CONFIG_ENDIAN_BIG``: define if big endian (default is little endian)
+
+* ``CONFIG_RAM_SIZE``: Describes the installed DRAM. One of:
+
+ * ``CONFIG_RAM_SIZE=(4*1024)``: (4Kb)
+ * ``CONFIG_RAM_SIZE=(8*1024)``: (8Kb)
+
+* ``CONFIG_RAM_START``: The start address of installed SRAM
+
+ * ``CONFIG_RAM_START=0x800100``
+
+* ``CONFIG_ARCH_LEDS``: Use LEDs to show state. Unique to boards that have LEDs
+
+* ``CONFIG_ARCH_INTERRUPTSTACK``: This architecture supports an interrupt
stack.
+ If defined, this symbol is the size of the interrupt stack in bytes. If not
+ defined, the user task stacks will be used during interrupt handling.
+
+* ``CONFIG_ARCH_STACKDUMP``: Do stack dumps after assertions
+
+* ``CONFIG_ARCH_LEDS``: Use LEDs to show state. Unique to board architecture.
+
+Individual subsystems can be enabled:
+
+* ``CONFIG_AVR_INT0=n``
+* ``CONFIG_AVR_INT1=n``
+* ``CONFIG_AVR_INT2=n``
+* ``CONFIG_AVR_INT3=n``
+* ``CONFIG_AVR_INT4=n``
+* ``CONFIG_AVR_INT5=n``
+* ``CONFIG_AVR_INT6=n``
+* ``CONFIG_AVR_INT7=n``
+* ``CONFIG_AVR_USBHOST=n``
+* ``CONFIG_AVR_USBDEV=n``
+* ``CONFIG_AVR_WDT=n``
+* ``CONFIG_AVR_TIMER0=n``
+* ``CONFIG_AVR_TIMER1=n``
+* ``CONFIG_AVR_TIMER2=n``
+* ``CONFIG_AVR_TIMER3=n``
+* ``CONFIG_AVR_SPI=n``
+* ``CONFIG_AVR_USART1=y``
+* ``CONFIG_AVR_ANACOMP=n``
+* ``CONFIG_AVR_ADC=n``
+* ``CONFIG_AVR_TWI=n``
+
+If the watchdog is enabled, this specifies the initial timeout. Default
+is maximum supported value.
+
+* ``CONFIG_WDTO_15MS``
+* ``CONFIG_WDTO_30MS``
+* ``CONFIG_WDTO_60MS``
+* ``CONFIG_WDTO_120MS``
+* ``CONFIG_WDTO_1250MS``
+* ``CONFIG_WDTO_500MS``
+* ``CONFIG_WDTO_1S``
+* ``CONFIG_WDTO_2S``
+* ``CONFIG_WDTO_4S``
+* ``CONFIG_WDTO_8S``
+
+AT90USB specific device driver settings:
+
+* ``CONFIG_USARTn_SERIAL_CONSOLE``: selects the USARTn for the console and
ttys0
+ (default is no serial console).
+* ``CONFIG_USARTn_RXBUFSIZE``: Characters are buffered as received. This
+ specific the size of the receive buffer
+* ``CONFIG_USARTn_TXBUFSIZE``: Characters are buffered before being sent. This
+ specific the size of the transmit buffer
+* ``CONFIG_USARTn_BAUD``: The configure BAUD of the USART. Must be
+* ``CONFIG_USARTn_BITS``: The number of bits. Must be either 7 or 8.
+* ``CONFIG_USARTn_PARTIY``: 0=no parity, 1=odd parity, 2=even parity
+* ``CONFIG_USARTn_2STOP``: Two stop bits
+
+Configurations
+==============
+
+1. Each Micropendous3 configuration is maintained in a sub-directory and
+ can be selected as follows:
+
+ .. code:: console
+
+ $ tools/configure.sh micropendous3:<subdir>
+
+ Where ``<subdir>`` is one of the configuration sub-directories described in
+ the following paragraph.
+
+ .. note::
+
+ You must also copy avr-libc header files, perhaps like:
+
+ .. code:: console
+
+ $ cp -a /cygdrive/c/WinAVR/include/avr include/.
+
+2. These configurations use the mconf-based configuration tool. To change a
+ configurations using that tool, you should:
+
+ a. Build and install the kconfig-mconf tool. See ``nuttx/README.txt``
+ see additional README.txt files in the NuttX tools repository.
+
+ b. Execute ``make menuconfig`` in ``nuttx/`` in order to start the
+ reconfiguration process.
+
+3. By default, all configurations assume the NuttX Buildroot toolchain
+ under Cygwin with Windows. This is easily reconfigured:
+
+ * ``CONFIG_HOST_WINDOWS=y``
+ * ``CONFIG_WINDOWS_CYGWIN=y``
+ * ``CONFIG_AVR_BUILDROOT_TOOLCHAIN=y``
+
+4. Build with GCC disables CONFIG_DEBUG_OPT_UNUSED_SECTIONS by default. This is
+ because the linker script was not checked to determine if it properly
+ prevents removal of sections which the linker considers unreferenced but
+ which must be present in the binary.
+
+hello
+-----
+
+The simple ``apps/examples/hello`` "Hello, World!" example.
+
+FLASH/SRAM Requirements (as of 6/16/2011):
+
+.. code:: console
+
+ $ avr-nuttx-elf-size nuttx
+ text data bss dec hex filename
+ 24816 978 308 26102 65f6 nuttx
+
+Strings are in SRAM.
