README ^^^^^^ This README discusses issues unique to NuttX configurations for the Atmel SAMD20 Xplained Pro development board. This board features the ATSAMD20J18A MCU. The SAMD20 Xplained Pro Starter Kit may be bundled with three modules: 1) I/O1 - An MMC/SD card slot, PWM LED control, ADC light sensor, USART loopback, TWI AT30TSE758 Temperature sensor. 2) OLED1 - An OLED plus 3 additional switches and 3 additional LEDs 3) PROTO1 - A prototyping board with logic on board (other than power-related logic). Contents ^^^^^^^^ - Modules - Development Environment - GNU Toolchain Options - IDEs - NuttX EABI "buildroot" Toolchain - LEDs - Serial Consoles - SAMD20 Xplained Pro-specific Configuration Options - Configurations Modules ^^^^^^^ The SAMD20 Xplained Pro Starter Kit is bundled with four modules: I/O1 ---- The primary function of this module is to provide SD card support, but the full list of modules features include: - microSD card connector (SPI interface) - PWM (LED control) - ADC (light sensor) - USART loopback - TWI AT30TSE758 Temperature sensor with EEPROM SPI is available on two of the SAMD20 Xplained connectors, EXT1 and EXT2. They mate with the I/O1 connector as indicated in this table. I/O1 CONNECTOR ----------------- ---------------------- ---------------------- ------------------------------------ I/O1 EXT1 EXT2 Other use of either pin ----------------- ---------------------- ---------------------- ------------------------------------ 1 ID 1 1 Communication line to ID chip on extension board. ----------------- ---------------------- ---------------------- ------------------------------------ 2 GND 2 GND 2 GND ----------------- ---------------------- ---------------------- ------------------------------------ 3 LIGHTSENSOR 3 PB00 AIN[8] 3 PA10 AIN[18] ----------------- ---------------------- ---------------------- ------------------------------------ 4 LP_OUT 4 PB01 AIN[9] 4 PA11 AIN[19] ----------------- ---------------------- ---------------------- ------------------------------------ 5 GPIO1 5 PB06 GPIO 5 PA20 GPIO ----------------- ---------------------- ---------------------- ------------------------------------ 6 GPIO2 6 PB07 GPIO 6 PA21 GPIO ----------------- ---------------------- ---------------------- ------------------------------------ 7 LED 7 PB02 TC6/WO[0] 7 PA22 TC4/WO[0] ----------------- ---------------------- ---------------------- ------------------------------------ 8 LP_IN 8 PB03 TC6/WO[1] 8 PA23 TC4/WO[1] ----------------- ---------------------- ---------------------- ------------------------------------ 9 TEMP_ALERT 9 PB04 EXTINT[4] 9 PB14 EXTINT[14] ----------------- ---------------------- ---------------------- ------------------------------------ 10 microSD_DETECT 10 PB05 GPIO 10 PB15 GPIO ----------------- ---------------------- ---------------------- ------------------------------------ 11 TWI SDA 11 PA08 SERCOM2 PAD[0] 11 PA08 SERCOM2 PAD[0] EXT1, EXT2, EXT3 and EDBG I²C SDA I²C SDA ----------------- ---------------------- ---------------------- ------------------------------------ 12 TWI SCL 12 PA09 SERCOM2 PAD[1] 12 PA09 SERCOM2 PAD[1] EXT2, EXT3 and EDBG I²C SCL I²C SCL ----------------- ---------------------- ---------------------- ------------------------------------ 13 USART RX 13 PB09 SERCOM4 PAD[1] 13 PB13 SERCOM4 PAD[1] The SERCOM4 module is shared between USART RX USART RX EXT1, 2 and 3 USART's, but uses different pins ----------------- ---------------------- ---------------------- ------------------------------------ 14 USART TX 14 PB08 SERCOM4 PAD[0] 14 PB12 SERCOM4 PAD[0] The SERCOM4 module is shared between USART TX USART TX EXT1, 2 and 3 USART's, but uses different pins ----------------- ---------------------- ---------------------- ------------------------------------ 15 microSD_SS 15 PA05 SERCOM0 PAD[1] 15 PA17 SERCOM1 PAD[1] SPI SS SPI SS ----------------- ---------------------- ---------------------- ------------------------------------ 16 SPI_MOSI 16 PA06 SERCOM0 PAD[2] 16 PA18 SERCOM1 PAD[2] SPI MOSI SPI MOSI ----------------- ---------------------- ---------------------- ------------------------------------ 17 SPI_MISO 17 PA04 SERCOM0 PAD[0] 17 PA16 SERCOM1 PAD[0] SPI MISO SPI MISO ----------------- ---------------------- ---------------------- ------------------------------------ 18 SPI_SCK 18 PA07 SERCOM0 PAD[3] 18 PA19 SERCOM1 PAD[3] SPI SCK SPI SCK ----------------- ---------------------- ---------------------- ------------------------------------ 19 GND 19 GND GND ----------------- ---------------------- ---------------------- ------------------------------------ 20 VCC 20 VCC VCC ----------------- ---------------------- ---------------------- ------------------------------------ The mapping between the I/O1 pins and the SD connector are shown in the following table. SD Card Connection ------------------ I/O1 SD PIN Description ---- ---- --- ------------------------------------------------- D2 1 Data line 2 (not used) 15 D3 2 Data line 3. Active low chip select, pulled high 16 CMD 3 Command line, connected to SPI_MOSI. 20 VDD 4 18 CLK 5 Clock line, connected to SPI_SCK. 2/19 GND 6 17 D0 7 Data line 0, connected to SPI_MISO. D1 8 Data line 1 (not used) 10 SW_A 9 Card detect 2/19 SW_B 10 GND Card Detect ----------- When a microSD card is put into the connector SW_A and SW_B are short- circuited. SW_A is connected to the microSD_DETECT signal. To use this as a card indicator remember to enable internal pullup in the target device. GPIOs ----- So all that is required to connect the SD is configure the SPI --- ------------------ ---------------------- ------------------------------------- PIN EXT1 EXT2 Description --- ------------------ ---------------------- ------------------------------------- 15 PA05 SERCOM0 PAD[1] 15 PA17 SERCOM1 PAD[1] Active low chip select OUTPUT, pulled SPI SS SPI SS high on board. --- ------------------ ---------------------- ------------------------------------- 10 PB05 GPIO 10 PB15 GPIO Active low card detect INPUT, must use internal pull-up. --- ------------------ ---------------------- ------------------------------------- Configuration Options: ---------------------- CONFIG_SAMD20_XPLAINED_IOMODULE=y : Informs the system that the I/O1 module is installed CONFIG_SAMD20_XPLAINED_IOMODULE_EXT1=y : The module is installed in EXT1 CONFIG_SAMD20_XPLAINED_IOMODULE_EXT2=y : The mdoule is installed in EXT2 See the set-up in the discussion of the nsh configuration below for other required configuration options. NOTE: As of this writing, only the SD card slot is supported in the I/O1 module. OLED1 ----- This module provides an OLED plus 3 additional switches and 3 additional LEDs. OLED1 CONNECTOR ----------------- ---------------------- ---------------------- ------------------------------------ OLED1 EXT1 EXT2 Other use of either pin ----------------- ---------------------- ---------------------- ------------------------------------ 1 ID 1 1 Communication line to ID chip on extension board. ----------------- ---------------------- ---------------------- ------------------------------------ 2 GND 2 GND 2 GND ----------------- ---------------------- ---------------------- ------------------------------------ 3 BUTTON2 3 PB00 AIN[8] 3 PA10 AIN[18] ----------------- ---------------------- ---------------------- ------------------------------------ 4 BUTTON3 4 PB01 AIN[9] 4 PA11 AIN[19] ----------------- ---------------------- ---------------------- ------------------------------------ 5 DATA_CMD_SEL 5 PB06 GPIO 5 PA20 GPIO ----------------- ---------------------- ---------------------- ------------------------------------ 6 LED3 6 PB07 GPIO 6 PA21 GPIO ----------------- ---------------------- ---------------------- ------------------------------------ 7 LED1 7 PB02 TC6/WO[0] 7 PA22 TC4/WO[0] ----------------- ---------------------- ---------------------- ------------------------------------ 8 LED2 8 PB03 TC6/WO[1] 8 PA23 TC4/WO[1] ----------------- ---------------------- ---------------------- ------------------------------------ 9 BUTTON1 9 PB04 EXTINT[4] 9 PB14 EXTINT[14] ----------------- ---------------------- ---------------------- ------------------------------------ 10 DISPLAY_RESET 10 PB05 GPIO 10 PB15 GPIO ----------------- ---------------------- ---------------------- ------------------------------------ 11 N/C 11 PA08 SERCOM2 PAD[0] 11 PA08 SERCOM2 PAD[0] EXT1, EXT2, EXT3 and EDBG I²C SDA I²C SDA ----------------- ---------------------- ---------------------- ------------------------------------ 12 N/C 12 PA09 SERCOM2 PAD[1] 12 PA09 SERCOM2 PAD[1] EXT2, EXT3 and EDBG I²C SCL I²C SCL ----------------- ---------------------- ---------------------- ------------------------------------ 13 N/C 13 PB09 SERCOM4 PAD[1] 13 PB13 SERCOM4 PAD[1] The SERCOM4 module is shared between USART RX USART RX EXT1, 2 and 3 USART's, but uses different pins ----------------- ---------------------- ---------------------- ------------------------------------ 14 N/C 14 PB08 SERCOM4 PAD[0] 14 PB12 SERCOM4 PAD[0] The SERCOM4 module is shared between USART TX USART TX EXT1, 2 and 3 USART's, but uses different pins ----------------- ---------------------- ---------------------- ------------------------------------ 15 DISPLAY_SS 15 PA05 SERCOM0 PAD[1] 15 PA17 SERCOM1 PAD[1] SPI SS SPI SS ----------------- ---------------------- ---------------------- ------------------------------------ 16 SPI_MOSI 16 PA06 SERCOM0 PAD[2] 16 PA18 SERCOM1 PAD[2] SPI MOSI SPI MOSI ----------------- ---------------------- ---------------------- ------------------------------------ 17 N/C 17 PA04 SERCOM0 PAD[0] 17 PA16 SERCOM1 PAD[0] SPI MISO SPI MISO ----------------- ---------------------- ---------------------- ------------------------------------ 18 SPI_SCK 18 PA07 SERCOM0 PAD[3] 18 PA19 SERCOM1 PAD[3] SPI SCK SPI SCK ----------------- ---------------------- ---------------------- ------------------------------------ 19 GND 19 GND GND ----------------- ---------------------- ---------------------- ------------------------------------ 20 VCC 20 VCC VCC ----------------- ---------------------- ---------------------- ------------------------------------ Configuration Options: ---------------------- CONFIG_SAMD20_XPLAINED_OLED1MODULE=y : Informs the system that the I/O1 module is installed CONFIG_SAMD20_XPLAINED_OLED1MODULE_EXT1=y : The module is installed in EXT1 CONFIG_SAMD20_XPLAINED_OLED1MODULE_EXT2=y : The mdoule is installed in EXT2 See the set-up in the discussion of the nsh configuration below for other required configuration options. PROTO1 ------ A prototyping board with logic on board (other than power-related logic). There is no built-in support for the PROTO1 module. Development Environment ^^^^^^^^^^^^^^^^^^^^^^^ Either Linux or Cygwin on Windows can be used for the development environment. The source has been built only using the GNU toolchain (see below). Other toolchains will likely cause problems. Testing was performed using the Cygwin environment. GNU Toolchain Options ^^^^^^^^^^^^^^^^^^^^^ The NuttX make system has been modified to support the following different toolchain options. 1. The CodeSourcery GNU toolchain, 2. The devkitARM GNU toolchain, ok 4. The NuttX buildroot Toolchain (see below). All testing has been conducted using the NuttX buildroot toolchain. To use the CodeSourcery, devkitARM or Raisonance GNU toolchain, you simply need to add one of the following configuration options to your .config (or defconfig) file: CONFIG_ARMV6M_TOOLCHAIN_CODESOURCERYW=y : CodeSourcery under Windows CONFIG_ARMV6M_TOOLCHAIN_CODESOURCERYL=y : CodeSourcery under Linux CONFIG_ARMV6M_TOOLCHAIN_ATOLLIC=y : Atollic toolchain for Windos CONFIG_ARMV6M_TOOLCHAIN_DEVKITARM=y : devkitARM under Windows CONFIG_ARMV6M_TOOLCHAIN_BUILDROOT=y : NuttX buildroot under Linux or Cygwin (default) CONFIG_ARMV6M_TOOLCHAIN_GNU_EABIL=y : Generic GCC ARM EABI toolchain for Linux CONFIG_ARMV6M_TOOLCHAIN_GNU_EABIW=y : Generic GCC ARM EABI toolchain for Windows If you are not using CONFIG_ARMV6M_TOOLCHAIN_BUILDROOT, then you may also have to modify the PATH in the setenv.h file if your make cannot find the tools. NOTE about Windows native toolchains ------------------------------------ The CodeSourcery (for Windows), Atollic, and devkitARM toolchains are Windows native toolchains. The CodeSourcery (for Linux), NuttX buildroot, and, perhaps, the generic GCC toolchains are Cygwin and/or Linux native toolchains. There are several limitations to using a Windows based 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. 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. MKDEP = $(TOPDIR)/tools/mknulldeps.sh NOTE 1: The CodeSourcery toolchain (2009q1) does not work with default optimization level of -Os (See Make.defs). It will work with -O0, -O1, or -O2, but not with -Os. NOTE 2: The devkitARM toolchain includes a version of MSYS make. Make sure that the paths to Cygwin's /bin and /usr/bin directories appear BEFORE the devkitARM path or will get the wrong version of make. IDEs ^^^^ NuttX is built using command-line make. It can be used with an IDE, but some effort will be required to create the project (There is a simple RIDE project in the RIDE subdirectory). Makefile Build -------------- Under Eclipse, it is pretty easy to set up an "empty makefile project" and simply use the NuttX makefile to build the system. That is almost for free under Linux. Under Windows, you will need to set up the "Cygwin GCC" empty makefile project in order to work with Windows (Google for "Eclipse Cygwin" - there is a lot of help on the internet). Native Build ------------ Here are a few tips before you start that effort: 1) Select the toolchain that you will be using in your .config file 2) Start the NuttX build at least one time from the Cygwin command line before trying to create your project. This is necessary to create certain auto-generated files and directories that will be needed. 3) Set up include pathes: You will need include/, arch/arm/src/sam34, arch/arm/src/common, arch/arm/src/armv7-m, and sched/. 4) All assembly files need to have the definition option -D __ASSEMBLY__ on the command line. Startup files will probably cause you some headaches. The NuttX startup file is arch/arm/src/sam34/sam_vectors.S. You may need to build NuttX one time from the Cygwin command line in order to obtain the pre-built startup object needed by RIDE. NuttX EABI "buildroot" Toolchain ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ A GNU GCC-based toolchain is assumed. The files */setenv.sh should be modified to point to the correct path to the Cortex-M0 GCC toolchain (if different from the default in your PATH variable). If you have no Cortex-M0 toolchain, one can be downloaded from the NuttX SourceForge download site (https://sourceforge.net/projects/nuttx/files/buildroot/). 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 samd20-xplained/ 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/cortexm0-eabi-defconfig-4.6.3 .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 details PLUS some special instructions that you will need to follow if you are building a Cortex-M0 toolchain for Cygwin under Windows. LEDs ^^^^ There is one yellow LED available on the SAM D20 Xplained Pro board that can be turned on and off. The LED can be activated by driving the connected PA14 I/O line to GND. When CONFIG_ARCH_LEDS is defined in the NuttX configuration, NuttX will control the LED as follows: SYMBOL Meaning LED0 ------------------- ----------------------- ------ LED_STARTED NuttX has been started OFF LED_HEAPALLOCATE Heap has been allocated OFF LED_IRQSENABLED Interrupts enabled OFF LED_STACKCREATED Idle stack created ON LED_INIRQ In an interrupt N/C LED_SIGNAL In a signal handler N/C LED_ASSERTION An assertion failed N/C LED_PANIC The system has crashed FLASH Thus is LED is statically on, NuttX has successfully booted and is, apparently, running normally. If LED is flashing at approximately 2Hz, then a fatal error has been detected and the system has halted. Serial Consoles ^^^^^^^^^^^^^^^ SERCOM4 ------ SERCOM4 is available on connectors EXT1 and EXT3 PIN EXT1 EXT3 GPIO Function ---- ---- ------ ----------- 13 PB09 PB13 SERCOM4 / USART RX 14 PB08 PB12 SERCOM4 / USART TX 19 19 GND 20 20 VCC If you have a TTL to RS-232 converter then this is the most convenient serial console to use. It is the default in all of these configurations. An option is to use the virtual COM port. Virtual COM Port ---------------- The SAMD20 Xplained Pro contains an Embedded Debugger (EDBG) that can be used to program and debug the ATSAMD20J18A using Serial Wire Debug (SWD). The Embedded debugger also include a Virtual Com port interface over SERCOM3. Virtual COM port connections: PA24 SERCOM3 / USART TXD PA25 SERCOM3 / USART RXD SAMD20 Xplained Pro-specific Configuration Options ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ CONFIG_ARCH - Identifies the arch/ subdirectory. This should be set to: CONFIG_ARCH=arm CONFIG_ARCH_family - For use in C code: CONFIG_ARCH_ARM=y CONFIG_ARCH_architecture - For use in C code: CONFIG_ARCH_CORTEXM0=y CONFIG_ARCH_CHIP - Identifies the arch/*/chip subdirectory CONFIG_ARCH_CHIP="samd" CONFIG_ARCH_CHIP_name - For use in C code to identify the exact chip: CONFIG_ARCH_CHIP_SAMD CONFIG_ARCH_CHIP_SAMD20 CONFIG_ARCH_CHIP_ATSAMD20J18 CONFIG_ARCH_BOARD - Identifies the configs subdirectory and hence, the board that supports the particular chip or SoC. CONFIG_ARCH_BOARD=samd20-xplained (for the SAMD20 Xplained Pro development board) CONFIG_ARCH_BOARD_name - For use in C code CONFIG_ARCH_BOARD_SAMD20_XPLAINED=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 (SRAM in this case): CONFIG_RAM_SIZE=0x00010000 (64KB) CONFIG_RAM_START - The start address of installed DRAM CONFIG_RAM_START=0x20000000 CONFIG_ARCH_IRQPRIO - The SAMD20 supports interrupt prioritization CONFIG_ARCH_IRQPRIO=y 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_SAMD_WDT - Watchdog Timer" CONFIG_SAMD_RTC - Real Time Counter" CONFIG_SAMD_NVMCTRL - Non-Volatile Memory Controller" CONFIG_SAMD_EVSYS - Event System" CONFIG_SAMD_SERCOM0 - Serial Communication Interface 0" CONFIG_SAMD_SERCOM1 - Serial Communication Interface 1" CONFIG_SAMD_SERCOM2 - Serial Communication Interface 2" CONFIG_SAMD_SERCOM3 - Serial Communication Interface 3" CONFIG_SAMD_SERCOM4 - Serial Communication Interface 4" CONFIG_SAMD_SERCOM5 - Serial Communication Interface 5" CONFIG_SAMD_TC0 - Timer/Counter 0" CONFIG_SAMD_TC1 - Timer/Counter 1" CONFIG_SAMD_TC2 - Timer/Counter 2" CONFIG_SAMD_TC3 - Timer/Counter 3" CONFIG_SAMD_TC4 - Timer/Counter 4" CONFIG_SAMD_TC5 - Timer/Counter 5" CONFIG_SAMD_TC6 - Timer/Counter 6" CONFIG_SAMD_TC7 - Timer/Counter 6" CONFIG_SAMD_ADC - Analog-to-Digital Converter" CONFIG_SAMD_AC - Analog Comparator" CONFIG_SAMD_DAC - Digital-to-Analog Converter" CONFIG_SAMD_PTC - Peripheral Touch Controller" Some subsystems can be configured to operate in different ways. The drivers need to know how to configure the subsystem. CONFIG_SAMD_SERCOM0_ISI2C, CONFIG_SAMD_SERCOM0_ISSPI, or CONFIG_SAMD_SERCOM0_ISUSART CONFIG_SAMD_SERCOM1_ISI2C, CONFIG_SAMD_SERCOM1_ISSPI, or CONFIG_SAMD_SERCOM1_ISUSART CONFIG_SAMD_SERCOM2_ISI2C, CONFIG_SAMD_SERCOM2_ISSPI, or CONFIG_SAMD_SERCOM2_ISUSART CONFIG_SAMD_SERCOM3_ISI2C, CONFIG_SAMD_SERCOM3_ISSPI, or CONFIG_SAMD_SERCOM3_ISUSART CONFIG_SAMD_SERCOM4_ISI2C, CONFIG_SAMD_SERCOM4_ISSPI, or CONFIG_SAMD_SERCOM4_ISUSART CONFIG_SAMD_SERCOM5_ISI2C, CONFIG_SAMD_SERCOM5_ISSPI, or CONFIG_SAMD_SERCOM5_ISUSART SAT91SAMD20 specific device driver settings CONFIG_USARTn_SERIAL_CONSOLE - selects the USARTn (n=0,1,2,..5) for the console and ttys0 (default is the USART4). 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 SAMD20 Xplained Pro configuration is maintained in a sub-directory and can be selected as follow: cd tools ./configure.sh samd20-xplained/ cd - . ./setenv.sh Before sourcing the setenv.sh file above, you should examine it and perform edits as necessary so that BUILDROOT_BIN is the correct path to the directory than holds your toolchain binaries. And then build NuttX by simply typing the following. At the conclusion of the make, the nuttx binary will reside in an ELF file called, simply, nuttx. make The that is provided above as an argument to the tools/configure.sh must be is one of the following. NOTE: These configurations use the mconf-based configuration tool. To change any of these configurations using that tool, you should: a. Build and install the kconfig-mconf tool. See nuttx/README.txt and misc/tools/ b. Execute 'make menuconfig' in nuttx/ in order to start the reconfiguration process. NOTES: 1. These configurations use the mconf-based configuration tool. To change any of these configurations using that tool, you should: a. Build and install the kconfig-mconf tool. See nuttx/README.txt and misc/tools/ b. Execute 'make menuconfig' in nuttx/ in order to start the reconfiguration process. 2. Unless stated otherwise, all configurations generate console output of on SERCOM4 which is available on EXT1 or EXT3 (see the section "Serial Consoles" above). The virtual COM port could be used, instead, by reconfiguring to use SERCOM3 instead of SERCOM4: System Type -> SAMD Peripheral Support CONFIG_SAMD_SERCOM3=y CONFIG_SAMD_SERCOM4=n Device Drivers -> Serial Driver Support -> Serial Console CONFIG_USART3_SERIAL_CONSOLE=y Device Drivers -> Serial Driver Support -> SERCOM4 Configuration CONFIG_USART3_2STOP=0 CONFIG_USART3_BAUD=115200 CONFIG_USART3_BITS=8 CONFIG_USART3_PARITY=0 CONFIG_USART3_RXBUFSIZE=256 CONFIG_USART3_TXBUFSIZE=256 3. Unless otherwise stated, the configurations are setup for Cygwin under Windows: Build Setup: CONFIG_HOST_WINDOWS=y : Windows Host CONFIG_WINDOWS_CYGWIN=y : Cygwin environment on windoes 4. These configurations use the CodeSourcery toolchain. But that is easily reconfigured: System Type -> Toolchain: CONFIG_ARMV6M_TOOLCHAIN_CODESOURCERYW=y Any re-configuration should be done before making NuttX or else the subsequent 'make' will fail. If you have already attempted building NuttX then you will have to 1) 'make distclean' to remove the old configuration, 2) 'cd tools; ./configure.sh sam3u-ek/ksnh' to start with a fresh configuration, and 3) perform the configuration changes above. Also, make sure that your PATH variable has the new path to your Atmel tools. Try 'which arm-none-eabi-gcc' to make sure that you are selecting the right tool. setenv.sh is available for you to use to set or PATH variable. The path in the that file may not, however, be correct for your installation. See also the "NOTE about Windows native toolchains" in the section call "GNU Toolchain Options" above. Configuration sub-directories ----------------------------- nsh: This configuration directory will built the NuttShell. See NOTES above and below: NOTES: 1. NOTE: If you get a compilation error like: libxx_new.cxx:74:40: error: 'operator new' takes type 'size_t' ('unsigned int') as first parameter [-fper Sometimes NuttX and your toolchain will disagree on the underlying type of size_t; sometimes it is an 'unsigned int' and sometimes it is an 'unsigned long int'. If this error occurs, then you may need to toggle the value of CONFIG_CXX_NEWLONG. 2. If the I/O1 module is connected to the SAMD20 Xplained Pro, then support for the SD card slot can be enabled by making the following changes to the configuration: File Systems: CONFIG_FS_FAT=y : Enable the FAT file system CONFIG_FAT_LCNAMES=y : Enable upper/lower case 8.3 file names (Optional, see below) CONFIG_FAT_LFN=y : Enable long file named (Optional, see below) CONFIG_FAT_MAXFNAME=32 : Maximum supported file name length There are issues related to patents that Microsoft holds on FAT long file name technologies. See the top level COPYING file for further details. System Type -> Peripherals: To be provided : Enable the SAMD20 SPI peripheral Device Drivers CONFIG_SPI=y : Enable SPI support CONFIG_SPI_EXCHANGE=y : The exchange() method is supported CONFIG_SPI_OWNBUS=y : Smaller code if this is the only SPI device CONFIG_MMCSD=y : Enable MMC/SD support CONFIG_MMCSD_NSLOTS=1 : Only one MMC/SD card slot CONFIG_MMCSD_MULTIBLOCK_DISABLE=n : Should not need to disable multi-block transfers CONFIG_MMCSD_HAVECARDDETECT=y : I/O1 module as a card detect GPIO CONFIG_MMCSD_SPI=y : Use the SPI interface to the MMC/SD card CONFIG_MMCSD_SPICLOCK=20000000 : This is a guess for the optimal MMC/SD frequency CONFIG_MMCSD_SPIMODE=0 : Mode 0 is required Board Selection -> Common Board Options CONFIG_NSH_MMCSDSLOTNO=0 : Only one MMC/SD slot, slot 0 CONFIG_NSH_MMCSDSPIPORTNO=0 : Use CS=0 if the I/O1 is in EXT1, OR CONFIG_NSH_MMCSDSPIPORTNO=2 : Use CS=2 if the I/O1 is in EXT2 Board Selection -> SAMD20 Xplained Pro Modules CONFIG_SAMD20_XPLAINED_IOMODULE=y : I/O1 module is connected CONFIG_SAMD20_XPLAINED_IOMODULE_EXT1=y : In EXT1, or EXT2 CONFIG_SAMD20_XPLAINED_IOMODULE_EXT2=y Application Configuration -> NSH Library CONFIG_NSH_ARCHINIT=y : Board has architecture-specific initialization NOTE: If you enable the I/O1 this configuration with SERCOM4 as the console and with the I/O1 module in EXT1, you *must* remove USART jumper. Otherwise, you have lookpack on SERCOM4 and NSH will *not* behave very well (since its outgoing prompts also appear as incoming commands). STATUS: As of 2013-6-18, this configuration appears completely functional. Testing, however, has been very light. Example: NuttShell (NSH) NuttX-6.34 nsh> mount -t vfat /dev/mmcsd0 /mnt/stuff nsh> ls /mnt/stuff /mnt/stuff: nsh> echo "This is a test" >/mnt/stuff/atest.txt nsh> ls /mnt/stuff /mnt/stuff: atest.txt nsh> cat /mnt/stuff/atest.txt This is a test nsh> 3. If the OLED1 module is connected to the SAMD20 Xplained Pro, then support for the OLED display can be enabled by making the following changes to the configuration: System Type -> Peripherals: To be provided : Enable the SAMD20 SPI peripheral Device Drivers -> SPI CONFIG_SPI=y : Enable SPI support CONFIG_SPI_EXCHANGE=y : The exchange() method is supported CONFIG_SPI_CMDDATA=y : CMD/DATA support is required CONFIG_SPI_OWNBUS=y : Smaller code if this is the only SPI device Device Drivers -> LCDs CONFIG_LCD=y : Enable LCD support CONFIG_LCD_MAXCONTRAST=255 : Maximum contrast value CONFIG_LCD_LANDSCAPE=y : Landscape orientation (see below*) CONFIG_LCD_UG2832HSWEG04=y : Enable support for the OLED CONFIG_LCD_SSD1306_SPIMODE=0 : SPI Mode 0 CONFIG_LCD_SSD1306_SPIMODE=3500000 : Pick an SPI frequency Board Selection -> SAMD20 Xplained Pro Modules CONFIG_SAMD20_XPLAINED_OLED1MODULE=y : OLED1 module is connected CONFIG_SAMD20_XPLAINED_OLED1MODULE_EXT1=y : In EXT1, or EXT2 CONFIG_SAMD20_XPLAINED_OLED1MODULE_EXT2=y The NX graphics subsystem also needs to be configured: CONFIG_NX=y : Enable graphics support CONFIG_NX_LCDDRIVER=y : Using an LCD driver CONFIG_NX_NPLANES=1 : With a single color plane CONFIG_NX_WRITEONLY=n : You can read from the LCD (see below**) CONFIG_NX_DISABLE_2BPP=y : Disable all resolutions except 1BPP CONFIG_NX_DISABLE_4BPP=y CONFIG_NX_DISABLE_8BPP=y CONFIG_NX_DISABLE_16BPP=y CONFIG_NX_DISABLE_24BPP=y CONFIG_NX_DISABLE_32BPP=y CONFIG_NX_PACKEDMSFIRST=y : LSB packed first (shouldn't matter) CONFIG_NXTK_BORDERWIDTH=2 : Use a small border CONFIG_NXTK_DEFAULT_BORDERCOLORS=y : Default border colors CONFIG_NXFONTS_CHARBITS=7 : 7-bit fonts CONFIG_NXFONT_SANS17X23B=y : Pick a font (any that will fit) * This orientation will put the buttons "above" the LCD. The reverse landscape configuration (CONFIG_LCD_RLANDSCAPE) will "flip" the display so that the buttons are "below" the LCD. ** The hardware is write only, but the driver maintains a frame buffer to support read and read-write-modiry operations on the LCD. Reading from the frame buffer is, however, untested. Then, in order to use the OLED, you will need to build some kind of graphics application or use one of the NuttX graphics examples. Here, for example, is the setup for the graphic "Hello, World!" example: CONFIG_EXAMPLES_NXHELLO=y : Enables the example CONFIG_EXAMPLES_NXHELLO_DEFAULT_COLORS=y : Use default colors (see below *) CONFIG_EXAMPLES_NXHELLO_DEFAULT_FONT=y : Use the default font CONFIG_EXAMPLES_NXHELLO_BPP=1 : One bit per pixel CONFIG_EXAMPLES_NXHELLO_EXTERNINIT=y : Special initialization is required. * The OLED is monochrome so the only "colors" are blacka nd white. The default "colors" will give you while text on a black background. You can override the faults it you want black text on a while background. NOTE: One issue that I have seen with the NXHello example when running as an NSH command is that it only works the first time. So, after you run the 'nxhello' command one time, you will have to reset the board before you run it again. This is clearly some issue with initializing, un-initializing, and then re-initializing. If you want to fix this, patches are quite welcome.