README ====== This README discusses issues unique to NuttX configurations for the Atmel SAMD21 Xplained Pro development board. This board features the ATSAMD21J18A MCU. The SAMD21 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 ======== - STATUS/ISSUES - Modules - LEDs - Serial Consoles - Atmel Studio 6.1 - SAMD21 Xplained Pro-specific Configuration Options - Configurations STATUS/ISSUES ============= 1. See boards/arm/samd2l2/samd20-xplained/README.txt. This port derives from the SAMD20 Xplained board board and all issues there should apply. 2. 2015-07-06: The basic NSH configuration is working properly, but not at 115200 baud which is the default BAUD selection in the configurations. It is necessary to drop the BAUD in the configuration. I suspect that this is an issue on my board and due to running the system on uncalibrated OSC8M. My bet is that the issue would not exist on many boards or if OSC8M were calibrated or if a more precise clock source were used (like XOSC32K). ... After more experimentation, I am not sure this conclusion is correct or not. Perhaps the board just comes up with a bad clocking configuration at times???? Modules ======= There are several I/O modules available that will work with the SAMD21 Xplained Pro Starter Kit: 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). 4) And others. See http://www.atmel.com/products/microcontrollers/avr/xplained.aspx Some of these are discussed further below. 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 SAMD21 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 PB12 TC4/WO[0] ----------------- ---------------------- ---------------------- ------------------------------------ 8 LP_IN 8 PB03 TC6/WO[1] 8 PB13 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 PB11 SERCOM4 PAD[1] EXT3 USART RX USART RX ----------------- ---------------------- ---------------------- ------------------------------------ 14 USART TX 14 PB08 SERCOM4 PAD[0] 14 PB10 SERCOM4 PAD[0] EXT3 USART TX USART TX ----------------- ---------------------- ---------------------- ------------------------------------ 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_SAMD21_XPLAINED_IOMODULE=y : Informs the system that the I/O1 module is installed CONFIG_SAMD21_XPLAINED_IOMODULE_EXT1=y : The module is installed in EXT1 CONFIG_SAMD21_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 PB12 TC4/WO[0] ----------------- ---------------------- ---------------------- ------------------------------------ 8 LED2 8 PB03 TC6/WO[1] 8 PB13 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 PB11 SERCOM4 PAD[1] EXT3 USART RX USART RX ----------------- ---------------------- ---------------------- ------------------------------------ 14 N/C 14 PB08 SERCOM4 PAD[0] 14 PB10 SERCOM4 PAD[0] EXT3 USART TX USART TX ----------------- ---------------------- ---------------------- ------------------------------------ 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_SAMD21_XPLAINED_OLED1MODULE=y : Informs the system that the I/O1 module is installed CONFIG_SAMD21_XPLAINED_OLED1MODULE_EXT1=y : The module is installed in EXT1 CONFIG_SAMD21_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. 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 PB30 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, EXT2, and EXT3, but using different PORT pins: PIN EXT1 EXT2 EXT3 GPIO Function ---- ---- ---- ---- ------------------ 13 PB09 PB10 PB10 SERCOM4 / USART RX 14 PB08 PB11 PB11 SERCOM4 / USART TX 19 GND GND GND N/A 20 VCC VCC VCC N/A There are options available in the NuttX configuration to select which connector SERCOM4 is on: SAMD21_XPLAINED_USART4_EXTn, where n=1, 2, or 3. If you have a TTL to RS-232 converter then this is the most convenient serial console to use (because you don't lose the console device each time you lose the USB connection). It is the default in all of these configurations. An option is to use the virtual COM port. Virtual COM Port ---------------- The SAMD21 Xplained Pro contains an Embedded Debugger (EDBG) that can be used to program and debug the ATSAMD21J18A using Serial Wire Debug (SWD). The Embedded debugger also include a Virtual COM port interface over SERCOM3. Virtual COM port connections: PA22 SERCOM3 / USART TXD PA23 SERCOM3 / USART RXD Atmel Studio 6.1 ================ Loading Code into FLASH: ----------------------- Tools menus: Tools -> Device Programming. Debugging the NuttX Object File ------------------------------- 1) Rename object file from nutt to nuttx.elf. That is an extension that will be recognized by the file menu. 2) File menu: File -> Open -> Open object file for debugging - Select nuttx.elf object file - Select AT91SAMD21J18 - Select files for symbols as desired - Select debugger 3) Debug menu: Debug -> Start debugging and break - This will reload the nuttx.elf file into FLASH SAMD21 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="samd2l2" CONFIG_ARCH_CHIP_name - For use in C code to identify the exact chip: CONFIG_ARCH_CHIP_SAMD2X CONFIG_ARCH_CHIP_SAMD21 CONFIG_ARCH_CHIP_ATSAMD21J18 CONFIG_ARCH_BOARD - Identifies the boards/ subdirectory and hence, the board that supports the particular chip or SoC. CONFIG_ARCH_BOARD=samd21-xplained (for the SAMD21 Xplained Pro development board) CONFIG_ARCH_BOARD_name - For use in C code CONFIG_ARCH_BOARD_SAMD21_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_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_SAMD2L2_AC - Analog Comparator CONFIG_SAMD2L2_ADC - Analog-to-Digital Converter CONFIG_SAMD2L2_DAC - Digital-to-Analog Converter CONFIG_SAMD2L2_DMAC - Analog Comparator CONFIG_SAMD2L2_EVSYS - Event System CONFIG_SAMD2L2_NVMCTRL - Non-Volatile Memory Controller CONFIG_SAMD2L2_PTC - Peripheral Touch Controller CONFIG_SAMD2L2_RTC - Real Time Counter CONFIG_SAMD2L2_SERCOM0 - Serial Communication Interface 0 CONFIG_SAMD2L2_SERCOM1 - Serial Communication Interface 1 CONFIG_SAMD2L2_SERCOM2 - Serial Communication Interface 2 CONFIG_SAMD2L2_SERCOM3 - Serial Communication Interface 3 CONFIG_SAMD2L2_SERCOM4 - Serial Communication Interface 4 CONFIG_SAMD2L2_SERCOM5 - Serial Communication Interface 5 CONFIG_SAMD2L2_TCC0 - Timer/Counter 0 for Control CONFIG_SAMD2L2_TCC1 - Timer/Counter 1 for Control CONFIG_SAMD2L2_TCC2 - Timer/Counter 2 for Control CONFIG_SAMD2L2_TC3 - Timer/Counter 3 CONFIG_SAMD2L2_TC4 - Timer/Counter 4 CONFIG_SAMD2L2_TC5 - Timer/Counter 5 CONFIG_SAMD2L2_TC6 - Timer/Counter 6 CONFIG_SAMD2L2_TC7 - Timer/Counter 6 CONFIG_SAMD2L2_USB - USB device or host CONFIG_SAMD2L2_WDT - Watchdog Timer Some subsystems can be configured to operate in different ways. The drivers need to know how to configure the subsystem. CONFIG_SAMD2L2_SERCOM0_ISI2C, CONFIG_SAMD2L2_SERCOM0_ISSPI, or CONFIG_SAMD2L2_SERCOM0_ISUSART CONFIG_SAMD2L2_SERCOM1_ISI2C, CONFIG_SAMD2L2_SERCOM1_ISSPI, or CONFIG_SAMD2L2_SERCOM1_ISUSART CONFIG_SAMD2L2_SERCOM2_ISI2C, CONFIG_SAMD2L2_SERCOM2_ISSPI, or CONFIG_SAMD2L2_SERCOM2_ISUSART CONFIG_SAMD2L2_SERCOM3_ISI2C, CONFIG_SAMD2L2_SERCOM3_ISSPI, or CONFIG_SAMD2L2_SERCOM3_ISUSART CONFIG_SAMD2L2_SERCOM4_ISI2C, CONFIG_SAMD2L2_SERCOM4_ISSPI, or CONFIG_SAMD2L2_SERCOM4_ISUSART CONFIG_SAMD2L2_SERCOM5_ISI2C, CONFIG_SAMD2L2_SERCOM5_ISSPI, or CONFIG_SAMD2L2_SERCOM5_ISUSART SAMD21 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 SAMD21 Xplained Pro configuration is maintained in a sub-directory and can be selected as follow: tools/configure.sh samd21-xplained: Before building, make sure the PATH environment variable include 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 see additional README.txt files in the NuttX tools repository. 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 see additional README.txt files in the NuttX tools repository. 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, EXT2, 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/L Peripheral Support CONFIG_SAMD2L2_SERCOM3=y : Enable one or both CONFIG_SAMD2L2_SERCOM4=n Device Drivers -> Serial Driver Support -> Serial Console CONFIG_USART4_SERIAL_CONSOLE=y : Select only one for the console CONFIG_USART4_SERIAL_CONSOLE=n Device Drivers -> Serial Driver Support -> SERCOM3 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 Device Drivers -> Serial Driver Support -> SERCOM4 Configuration CONFIG_USART4_2STOP=0 CONFIG_USART4_BAUD=115200 CONFIG_USART4_BITS=8 CONFIG_USART4_PARITY=0 CONFIG_USART4_RXBUFSIZE=256 CONFIG_USART4_TXBUFSIZE=256 Board Selection -> USART4 Connection CONFIG_SAMD21_XPLAINED_USART4_EXT1=n : Pick on if USART4 used CONFIG_SAMD21_XPLAINED_USART4_EXT2=n CONFIG_SAMD21_XPLAINED_USART4_EXT3=y 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) '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. See also the "NOTE about Windows native toolchains" in the section called "GNU Toolchain Options" above. Configuration sub-directories ----------------------------- nsh: This configuration directory will built the NuttShell. See NOTES above and below: NOTES: 1. This configuration is set up to build on Windows using the Cygwin environment using the CodeSourcery toolchain. This can be easily changed as described above under "Configurations." 2. By default, this configuration provides a serial console on SERCOM4 at 115200 8N1 via EXT3: PIN EXT3 GPIO Function ---- ---- ------------------ 13 PB11 SERCOM4 / USART RX 14 PB10 SERCOM4 / USART TX 19 GND N/A 20 VCC N/A If you would prefer to use the EDBG serial COM port or would prefer to use SERCOM4 on EXT1 or EXT2, you will need to reconfigure the SERCOM as described under "Configurations". See also the section entitled "Serial Consoles" above. 3. 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_ARCH_SIZET_LONG. 4. If the I/O1 module is connected to the SAMD21 Xplained Pro, then support for the SD card slot can be enabled by making the following changes to the configuration. These changes assume that the I/O1 modules is connected in EXT1. Most of the modifications necessary to work with the I/O1 in a different connector are obvious.. except for the selection of SERCOM SPI support: EXT1: SPI is provided through SERCOM0 EXT2: SPI is provided through SERCOM1 EXT3: SPI is provided through SERCOM5 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: CONFIG_SAMD2L2_SERCOM0=y : Use SERCOM0 if the I/O is in EXT1 CONFIG_SAMD2L2_SERCOM0_ISSPI=y : Configure SERCOM0 as an SPI master Device Drivers CONFIG_SPI=y : Enable SPI support CONFIG_SPI_EXCHANGE=y : The exchange() method is supported 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_MMCSUPPORT=n : May interfere with some SD cards CONFIG_MMCSD_HAVE_CARDDETECT=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 port=0 -> SERCOM0 if the I/O1 is in EXT1 Board Selection -> SAMD21 Xplained Pro Modules CONFIG_SAMD21_XPLAINED_IOMODULE=y : I/O1 module is connected CONFIG_SAMD21_XPLAINED_IOMODULE_EXT1=y : I/O1 modules is in EXT1 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> 5. If the OLED1 module is connected to the SAMD21 Xplained Pro, then support for the OLED display can be enabled by making the following changes to the configuration. These changes assume that the I/O1 modules is connected in EXT1. Most of the modifications necessary to work with the I/O1 in a different connector are obvious.. except for the selection of SERCOM SPI support: EXT1: SPI is provided through SERCOM0 EXT2: SPI is provided through SERCOM1 EXT3: SPI is provided through SERCOM5 System Type -> Peripherals: CONFIG_SAMD2L2_SERCOM1=y : Use SERCOM1 if the I/O is in EXT2 CONFIG_SAMD2L2_SERCOM1_ISSPI=y : Configure SERCOM1 as an SPI master 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 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 -> SAMD21 Xplained Pro Modules CONFIG_SAMD21_XPLAINED_OLED1MODULE=y : OLED1 module is connected CONFIG_SAMD21_XPLAINED_OLED1MODULE_EXT2=y : OLED1 modules is in EXT2 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_NXSTART_EXTERNINIT=y : We have board_graphics_setup() 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.