README ====== This README discusses the port of NuttX to the STMicro B-L475E-IOT01A Discovery kit powered by STM32L475VG Cortex-M4. This board targets IoT nodes with a choice of connectivity options including WiFi, Bluetooth LE, NFC, and sub-GHZ RF at 868 or 915 MHz, as well as a long list of various environmental sensors. Contents ======== o STATUS o Board Features o LEDs and Buttons o Serial Console o Configurations STATUS ====== o 2017-06-10: I have no hardware in hand and I am not sure that I will even pursue this port. This README is really no more than a thought experiment at the present time. A few days ago, I did add support for the STM32L4x5 MCU family to NuttX. But no work has yet been done for this board port other than writing this README file. o 2017-06-13: I just learned that development boards will not be available for another month. Board Features ============== B-L475E-IOT01A Discovery kit key features and specifications: o MCU: STM32L475 Series MCU based on ARM Cortex-M4 core with 1 MB Flash memory, 128 KB SRAM o Storage: 64 Mbit (8MB)  Quad-SPI Flash memory (Macronix) o Connectivity: - Bluetooth 4.1 LE module (SPBTLE-RF) - Sub-GHz (868 or 915 MHz) low-power-programmable RF module (SPSGRF-868 or SPSGRF-915) - Wi-Fi module based on Inventek ISM43362-M3G-L44 (802.11 b/g/n compliant) - Dynamic NFC tag based on M24SR with its printed NFC antenna o Sensors: - 2x digital omni-directional microphones (MP34DT01) - Capacitive digital sensor for relative humidity and temperature (HTS221) - 3-axis magnetometer (LIS3MDL) - 3D accelerometer and 3D gyroscope (LSM6DSL) - 260-1260 hPa absolute digital output barometer (LPS22HB) - Time-of-Flight and gesture-detection sensor (VL53L0X o USB – 1x micro USB OTG port (Full speed) o Expansion – Arduino UNO V3 headers, PMOD header o Debugging – On-board ST-LINK/V2-1 debugger/programmer with USB re-enumeration capability: mass storage, virtual COM port and debug port o Misc – 2 push-buttons (user and reset) o Power Supply – 5V via ST LINK USB VBUS or external sources The board supports ARM mbed online compiler, but can also be programmed using IDEs such as IAR, Keil, and GCC-based IDEs. STMicro also provides HAL libraries and code samples as part of the STM32Cube Package, as well as X-CUBE-AWS expansion software to connect to the Amazon Web Services (AWS) IoT platform. NOTES: 1. The board usese Wi-Fi® module Inventek ISM43362-M3G-L44 (802.11 b/g/n compliant), which consists of BCM43362 and STM32F205 host processor that has a standard SPI or UART interface capability. It means you will only use AT command to talk with Wi-Fi® module by SPI. All the tcp/ip stack is built-in STM32F205 in Wi-Fi® module. This cannot integrate cleanly with the NuttX network stack. A USERSOCK option was recently added that would permit implementation of the Inventek support in an applications. But that would then preclude the 6LoWPAN integration into IPv6. 2. The board uses Bluetooth® V4.1 module (SPBTLE-RF), which has built-in BLE stack. Similar with wifi, you only use simple AT command to talk with this BLE module. 3. STMicro provides contiki 6lowpan for mesh. http://www.st.com/en/embedded-software/osxcontiki6lp.html but mesh network is not popular in the market, star network is the mainstream for its simplicity and robustness. LEDs and Buttons ================ The black button B1 located on top side is the reset of the STM32L475VGT6. The blue button B1 located top side is available to be used as a digital input or as alternate function Wake-up. When the button is depressed the logic state is "0", otherwise the logic state is "1". Two green LEDs (LD1 and LD2), located on the top side are available for the user. To light a LED a high logic state "1" should be written in the corresponding GPIO. Reference Color Name Comment B2 blue Wake-up Alternate function Wake-up LD1 green LED1 PA5 (alternate with ARD.D13) LD2 green LED2 PB14 These LEDs are not used by the board port unless CONFIG_ARCH_LEDS is selected. In that case, the usage by the board port is defined in include/board.h and src/lpc31_leds.c. The LEDs are used to encode OS-related events as follows: SYMBOL Meaning LED state LED2 LED1 ------------------- ----------------------- -------- -------- LED_STARTED NuttX has been started OFF OFF LED_HEAPALLOCATE Heap has been allocated OFF OFF LED_IRQSENABLED Interrupts enabled OFF OFF LED_STACKCREATED Idle stack created ON OFF LED_INIRQ In an interrupt N/C N/C LED_SIGNAL In a signal handler N/C N/C LED_ASSERTION An assertion failed N/C N/C LED_PANIC The system has crashed N/C Blinking LED_IDLE MCU is is sleep mode Not used Thus if LED2 is statically on, NuttX has successfully booted and is, apparently, running normmally. If LED1 is flashing at approximately 2Hz, then a fatal error has been detected and the system has halted. NOTE: That LED2 is not used after completion of booting and may be used by other board-specific logic. Of course, if CONFIG_ARCH_LEDS is not selected, then both LEDs are available for use by other logic. Serial Console ============== Arduino Serial Shield --------------------- An TLL-to-RS232 Converter shield may be used with UART4: UART4: -------------- ---------------- ------------------ STM32L475VGTx Board Signal Arduino Connector -------------- ---------------- ------------------ UART4_RX PA1 ARD.D0-UART4_RX CN3 pin1 RX/D0 UART4_TX PA0 ARD.D1-UART4_TX CN3 pin2 TX/D1 -------------- ---------------- ------------------ Virtual COM Port ---------------- The serial interface USART1 is directly available as a virtual COM port of the PC connected to the ST-LINK/V2-1 USB connector CN7. USART1: -------------- ---------------- -------------- STM32L475VGTx Board Signal STM32F103CBT6 -------------- ---------------- -------------- USART1_TX PB6 ST-LINK-UART1_TX USART2_RX PA3 UAART1_RX PB7 ST-LINK-UART1_RX USART2_TX PA2 -------------- ---------------- -------------- The virtual COM port settings are configured as: 115200 b/s, 8 bits data, no parity, 1 stop bit, no flow control. Other Options ------------- USART2 - Available on CN10 if solder bridges closed. -------------- ---------------- --------------------------- STM32L475VGTx Board Signal PMOD / Solder Bridges -------------- ---------------- --------------------------- USART2_RX PD4 PMOD-UART2_RX CN10 pin1 or 2 (SB12, SB14) USART2_TX PD5 PMOD-UART2_TX CN10 pin2 TX/D1 (SB20) -------------- ---------------- --------------------------- USART3 - Dedicated to ISM43362-M3G-L44 Serial-to-Wifi Module. -------------- ---------------- ------------------ STM32L475VGTx Board Signal Arduino Connector -------------- ---------------- ------------------ USART3_RX PD9 INTERNAL-UART3_RX CN3 pin1 RX/D0 USART3_TX PD8 INTERNAL-UART3_TX CN3 pin2 TX/D1 -------------- ---------------- ------------------ Configurations ============== Information Common to All Configurations ---------------------------------------- Each B-L475E-IOT01A configuration is maintained in a sub-directory and can be selected as follow: cd tools ./configure.sh b-l475e-iot01a/ cd - Before building, make sure that: 1. The PATH environment variable include the correct path to the directory than holds your toolchain binaries. 2. Check the .config file. Make sure that the configuration is set for your build platform (e.g., Linux vs. Windows) and that the toolchain is set for the toolchain type you are using. The that is provided above as an argument to the tools/configure.sh must be is one of those listed below. 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 oldconfig make Where 'make oldconfig' brings the configuration up to data with the current configuration data and 'make' will compile all of the source files and generate the final binary. 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 on USART1 (i.e., for ST-Link Virtual COM port). 3. All of these configurations are set up to build under Windows using the "GNU Tools for ARM Embedded Processors" that is maintained by ARM (unless stated otherwise in the description of the configuration). https://launchpad.net/gcc-arm-embedded That toolchain selection can easily be reconfigured using 'make menuconfig'. Here are the relevant current settings: Build Setup: CONFIG_HOST_WINDOWS=y : Window environment CONFIG_WINDOWS_CYGWIN=y : Cywin under Windows System Type -> Toolchain: CONFIG_ARMV7M_TOOLCHAIN_GNU_EABIW=y : GNU ARM EABI toolchain Configuration sub-directories -----------------------------