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 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 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 Toolchains ^^^^^^^^^^ Buildroot: There is a DIY buildroot version for the AVR boards here: http://sourceforge.net/projects/nuttx/files/buildroot/. See the following section for details on building this toolchain. It is assumed in some places that buildroot toolchain is available at ../misc/buildroot/build_avr. Edit the setenv.sh file if this is not the case. After configuring NuttX, make sure that CONFIG_AVR_BUILDROOT=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/ It is assumed in some places that WinAVR is installed at C:/WinAVR. Edit the setenv.sh file if this is not the case. After configuring NuttX, make sure that CONFIG_AVR_WINAVR=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=y is set in your .config file. 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 not 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. 3. Dependencies are not made when using Windows versions of the GCC. This is because the dependencies are generated using Windows pathes which do not work with the Cygwin make. Support has been added for making dependencies with the windows-native toolchains. That support can be enabled by modifying your Make.defs file as follows: - MKDEP = $(TOPDIR)/tools/mknulldeps.sh + MKDEP = $(TOPDIR)/tools/mkdeps.sh --winpaths "$(TOPDIR)" If you have problems with the dependency build (for example, if you are not building on C:), then you may need to modify tools/mkdeps.sh 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 SourceForge download site (https://sourceforge.net/projects/nuttx/files/). This GNU toolchain builds and executes in the Linux or Cygwin environment. 1. You must have already configured Nuttx in /nuttx. cd tools ./configure.sh micropendous3/ 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 3. unpack the buildroot tarball. The resulting directory may have versioning information on it like buildroot-x.y.z. If so, rename /buildroot-x.y.z to /buildroot. 4. cd /buildroot 5. cp configs/avr-defconfig-4.5.2 .config 6. make oldconfig 7. make 8. Edit setenv.h, if necessary, so that the PATH variable includes the path to the newly built binaries. See the file configs/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 /include/avr /include/. Or simply using a symbolic link: ln -s /include/avr /include/. Build Notes: It may not necessary to have a built version of avr-lib; only header files are required. Bu if you choose to use the optimized libraru functions of the flowing 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. Upack 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_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 configs 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_DRAM_SIZE - Describes the installed DRAM. One of: CONFIG_DRAM_SIZE=(4*1024) - (4Kb) CONFIG_DRAM_SIZE=(8*1024) - (8Kb) CONFIG_DRAM_START - The start address of installed DRAM CONFIG_DRAM_START=0x10000000 CONFIG_DRAM_END - Last address+1 of installed RAM CONFIG_DRAM_END=(CONFIG_DRAM_START+CONFIG_DRAM_SIZE) 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. CONFIG_ARCH_CALIBRATION - Enables some build in instrumentation that cause a 100 second delay during boot-up. This 100 second delay serves no purpose other than it allows you to calibratre CONFIG_ARCH_LOOPSPERMSEC. You simply use a stop watch to measure the 100 second delay then adjust CONFIG_ARCH_LOOPSPERMSEC until the delay actually is 100 seconds. 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 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 ^^^^^^^^^^^^^^ Each Micropendous3 configuration is maintained in a sudirectory and can be selected as follow: cd tools ./configure.sh micropendous3/ cd - . ./setenv.sh NOTE: You must also copy avr-libc header files, perhaps like: cp -a /cygdrive/c/WinAVR/include/avr include/. Where is one of the following: ostest: This configuration directory, performs a simple OS test using apps/examples/ostest.