README.txt ========== This README file discuss discusses the port of NuttX to the Texas Instruments DK-TM4C129x Connected Development Kit. Description ----------- The Tiva™ C Series TM4C129x Connected Development Kit highlights the 120-MHz Tiva C Series TM4C129XNCZAD ARM® Cortex™-M4 based microcontroller, including an integrated 10/100 Ethernet MAC + PHY as well as many other key features. Features -------- - Color LCD interface - USB 2.0 OTG | Host | Device port - TI wireless EM connection - BoosterPack and BoosterPack XL interfaces - Quad SSI-supported 512-Mbit Flash memory - MicroSD slot - Expansion interface headers: MCU high-speed USB ULPI port, Ethernet RMII and MII ports External peripheral interface for memories, parallel peripherals, and other system functions. - In-Circuit Debug Interface (ICDI) Using OpenOCD and GDB with ICDI =============================== Building OpenOCD under Cygwin: Refer to configs/olimex-lpc1766stk/README.txt Installing OpenOCD in Linux: sudo apt-get install openocd You can also build openocd from its source: git clone http://git.code.sf.net/p/openocd/code openocd cd openocd Helper Scripts: I have been using the on-board In-Circuit Debug Interface (ICDI) interface. OpenOCD requires a configuration file. I keep the one I used last here: configs/dk-tm4c129x/tools/dk-tm4c129x.cfg However, the "correct" configuration script to use with OpenOCD may change as the features of OpenOCD evolve. So you should at least compare that dk-tm4c129x.cfg file with configuration files in /usr/share/openocd/scripts. As of this writing, the configuration files of interest were: /usr/local/share/openocd/scripts/board/dk-tm4c129x.cfg /usr/local/share/openocd/scripts/interface/ti-icdi.cfg /usr/local/share/openocd/scripts/target/stellaris_icdi.cfg There is also a script on the tools/ directory that I use to start the OpenOCD daemon on my system called oocd.sh. That script will probably require some modifications to work in another environment: - Possibly the value of OPENOCD_PATH and TARGET_PATH - It assumes that the correct script to use is the one at configs/dk-tm4c129x/tools/dk-tm4c129x.cfg Starting OpenOCD If you are in the top-level NuttX build directlory then you should be able to start the OpenOCD daemon like: oocd.sh $PWD The relative path to the oocd.sh script is configs/dk-tm4c129x/tools, but that should have been added to your PATH variable when you sourced the setenv.sh script. Note that OpenOCD needs to be run with administrator privileges in some environments (sudo). Connecting GDB Once the OpenOCD daemon has been started, you can connect to it via GDB using the following GDB command: arm-nuttx-elf-gdb (gdb) target remote localhost:3333 NOTE: The name of your GDB program may differ. For example, with the CodeSourcery toolchain, the ARM GDB would be called arm-none-eabi-gdb. After starting GDB, you can load the NuttX ELF file: (gdb) symbol-file nuttx (gdb) monitor reset (gdb) monitor halt (gdb) load nuttx NOTES: 1. Loading the symbol-file is only useful if you have built NuttX to include debug symbols (by setting CONFIG_DEBUG_SYMBOLS=y in the .config file). 2. The MCU must be halted prior to loading code using 'mon reset' as described below. OpenOCD will support several special 'monitor' commands. These GDB commands will send comments to the OpenOCD monitor. Here are a couple that you will need to use: (gdb) monitor reset (gdb) monitor halt NOTES: 1. The MCU must be halted using 'mon halt' prior to loading code. 2. Reset will restart the processor after loading code. 3. The 'monitor' command can be abbreviated as just 'mon'. 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 NuttX buildroot Toolchain (default, see below), 2. The CodeSourcery GNU toolchain, 3. The devkitARM GNU toolchain, 4. The Atollic toolchain, or 5. The Code Red toolchain All testing has been conducted using the Buildroot toolchain for Cygwin/Linux. To use a different toolchain, you simply need to add one of the following configuration options to your .config (or defconfig) file: CONFIG_ARMV7M_TOOLCHAIN_BUILDROOT=y : NuttX buildroot under Linux or Cygwin (default) CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYW=y : CodeSourcery under Windows or Cygwin CONFIG_ARMV7M_TOOLCHAIN_CODESOURCERYL=y : CodeSourcery under Linux CONFIG_ARMV7M_TOOLCHAIN_DEVKITARM=y : The Atollic toolchain under Windows or Cygwin CONFIG_ARMV7M_TOOLCHAIN_CODEREDW=y : The Code Red toolchain under Windows CONFIG_ARMV7M_TOOLCHAIN_CODEREDL=y : The Code Red toolchain under Linux CONFIG_ARMV7M_OABI_TOOLCHAIN=y : If you use an older, OABI buildroot toolchain If you change the default toolchain, then you may also have to modify the PATH in the setenv.h file if your make cannot find the tools. NOTE: the CodeSourcery (for Windows), Atollic, devkitARM, and Code Red (for Windows) toolchains are Windows native toolchains. The CodeSourcey (for Linux) and NuttX buildroot 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) did not work with default optimization level of -Os (See Make.defs). It will work with -O0, -O1, or -O2, but not with -Os. I have not seen this problem with current toolchains. 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. 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 paths: You will need include/, arch/arm/src/tiva, 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/tiva/tiva_vectors.S. 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-M3 GCC toolchain (if different from the default in your PATH variable). If you have no Cortex-M3 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 dk-tm4c129x/ 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/cortexm3-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-M3 toolchain for Cygwin under Windows. NOTE: Unfortunately, the 4.6.3 EABI toolchain is not compatible with the the NXFLAT tools. See the top-level TODO file (under "Binary loaders") for more information about this problem. If you plan to use NXFLAT, please do not use the GCC 4.6.3 EABI toochain; instead use the GCC 4.3.3 OABI toolchain. See instructions below. NuttX OABI "buildroot" Toolchain ================================ The older, OABI buildroot toolchain is also available. To use the OABI toolchain: 1. When building the buildroot toolchain, either (1) modify the cortexm3-eabi-defconfig-4.6.3 configuration to use EABI (using 'make menuconfig'), or (2) use an exising OABI configuration such as cortexm3-defconfig-4.3.3 2. Modify the Make.defs file to use the OABI conventions: +CROSSDEV = arm-nuttx-elf- +ARCHCPUFLAGS = -mtune=cortex-m3 -march=armv7-m -mfloat-abi=soft +NXFLATLDFLAGS2 = $(NXFLATLDFLAGS1) -T$(TOPDIR)/binfmt/libnxflat/gnu-nxflat-gotoff.ld -no-check-sections -CROSSDEV = arm-nuttx-eabi- -ARCHCPUFLAGS = -mcpu=cortex-m3 -mthumb -mfloat-abi=soft -NXFLATLDFLAGS2 = $(NXFLATLDFLAGS1) -T$(TOPDIR)/binfmt/libnxflat/gnu-nxflat-pcrel.ld -no-check-sections NXFLAT Toolchain ================ If you are *not* using the NuttX buildroot toolchain and you want to use the NXFLAT tools, then you will still have to build a portion of the buildroot tools -- just the NXFLAT tools. The buildroot with the NXFLAT tools 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 dk-tm4c129x/ 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/cortexm3-defconfig-nxflat .config 6. make oldconfig 7. make 8. Edit setenv.h, if necessary, so that the PATH variable includes the path to the newly builtNXFLAT binaries. Buttons and LEDs ================ Buttons ------- There are three push buttons on the board. --- ------------ ----------------- Pin Pin Function Jumper --- ------------ ----------------- PP1 Select SW4 J37 pins 1 and 2 PN3 Up SW2 J37 pins 3 and 4 PE5 Down SW3 J37 pins 5 and 6 --- ------------ ----------------- LEDs ---- The development board has one tri-color user LED. --- ------------ ----------------- Pin Pin Function Jumper --- ------------ ----------------- PN5 Red LED J36 pins 1 and 2 PQ4 Blue LED J36 pins 3 and 4 PQ7 Green LED J36 pins 5 and 6 --- ------------ ----------------- If CONFIG_ARCH_LEDS is not defined, this LED is not used by the NuttX logic. APIs are provided to support application control of the LED in that case (in include/board.h and src/tm4c_userleds.c). If CONFIG_ARCH_LEDS is defined then the usage of the LEDs by Nuttx is defined in include/board.h and src/tm4c_autoleds.c. The LEDs are used to encode OS-related events as follows: SYMBOL Meaning LED state ------------------- ----------------------- -------- -------- LED_STARTED NuttX has been started Blue LED_HEAPALLOCATE Heap has been allocated (No change) LED_IRQSENABLED Interrupts enabled (No change) LED_STACKCREATED Idle stack created Green LED_INIRQ In an interrupt (No change) LED_SIGNAL In a signal handler (No change) LED_ASSERTION An assertion failed (No change) LED_PANIC The system has crashed Blinking OFF/RED LED_IDLE MCU is is sleep mode (Not used) Thus if the LED is GREEN then NuttX has successfully booted and is, apparently, running normally. If the LED is flashing OFF/RED at approximately 2Hz, then a fatal error has been detected and the system has halted. Serial Console ============== By default, all configurations use UART0 which connects to the USB VCOM on the DEBUG port on the TM4C123 ICDI interface: UART0 RX - PA.0 UART0 TX - PA.1 However, if you use an external RS232 driver, then other options are available. If your serial terminal loses connection with the USB serial port each time you power cycle the board, the VCOM option can be very painful. UART0 TTL level signals are also available at J3 (also at J1): DEBUG_TX - J3, pin 13. Labelled PA1 DEBUG_RX - J3, pin 15. Labelled PA0 Remove the jumper between pins 13-14 and 15-16 to disconnect UART0 from the TM4C123 ICDI chip; Connect your external RS-232 driver at pins 13 and 16. 5v, 3.3v, AND GND are arvailable nearby at J10. DK-TM4129X 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_CORTEXM4=y CONFIG_ARCH_CHIP - Identifies the arch/*/chip subdirectory CONFIG_ARCH_CHIP="tiva" CONFIG_ARCH_CHIP_name - For use in C code to identify the exact chip: CONFIG_ARCH_CHIP_TM4C129XNC CONFIG_ARCH_BOARD - Identifies the configs subdirectory and hence, the board that supports the particular chip or SoC. CONFIG_ARCH_BOARD=dk-tm4c129x (for the DK-TM4129X) CONFIG_ARCH_BOARD_name - For use in C code CONFIG_ARCH_BOARD_DK_TM4C129X 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=0x00008000 (32Kb) 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. 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. There are configurations for disabling support for interrupts GPIO ports. Only GPIOP and GPIOQ pins can be used as interrupting sources on the TM4C129x. Additional interrupt support can be disabled if desired to reduce memory footprint. CONFIG_TIVA_GPIOP_IRQS=y CONFIG_TIVA_GPIOQ_IRQS=y TM4C129x specific device driver settings CONFIG_UARTn_SERIAL_CONSOLE - selects the UARTn for the console and ttys0 (default is the UART0). CONFIG_UARTn_RXBUFSIZE - Characters are buffered as received. This specific the size of the receive buffer CONFIG_UARTn_TXBUFSIZE - Characters are buffered before being sent. This specific the size of the transmit buffer CONFIG_UARTn_BAUD - The configure BAUD of the UART. Must be CONFIG_UARTn_BITS - The number of bits. Must be either 7 or 8. CONFIG_UARTn_PARTIY - 0=no parity, 1=odd parity, 2=even parity CONFIG_UARTn_2STOP - Two stop bits CONFIG_TIVA_SSI0 - Select to enable support for SSI0 CONFIG_TIVA_SSI1 - Select to enable support for SSI1 CONFIG_SSI_POLLWAIT - Select to disable interrupt driven SSI support. Poll-waiting is recommended if the interrupt rate would be to high in the interrupt driven case. CONFIG_SSI_TXLIMIT - Write this many words to the Tx FIFO before emptying the Rx FIFO. If the SPI frequency is high and this value is large, then larger values of this setting may cause Rx FIFO overrun errors. Default: half of the Tx FIFO size (4). CONFIG_TIVA_ETHERNET - This must be set (along with CONFIG_NET) to build the Tiva Ethernet driver CONFIG_TIVA_ETHLEDS - Enable to use Ethernet LEDs on the board. CONFIG_TIVA_BOARDMAC - If the board-specific logic can provide a MAC address (via tiva_ethernetmac()), then this should be selected. CONFIG_TIVA_ETHHDUPLEX - Set to force half duplex operation CONFIG_TIVA_ETHNOAUTOCRC - Set to suppress auto-CRC generation CONFIG_TIVA_ETHNOPAD - Set to suppress Tx padding CONFIG_TIVA_MULTICAST - Set to enable multicast frames CONFIG_TIVA_PROMISCUOUS - Set to enable promiscuous mode CONFIG_TIVA_BADCRC - Set to enable bad CRC rejection. CONFIG_TIVA_DUMPPACKET - Dump each packet received/sent to the console. Configurations ============== Each DK-TM4129X configuration is maintained in a sub-directory and can be selected as follow: cd tools ./configure.sh dk-tm4c129x/ cd - . ./setenv.sh Where is one of the following: nsh: --- Configures the NuttShell (nsh) located at apps/examples/nsh. The configuration enables the serial VCOM interfaces on UART0. Support for builtin applications is enabled, but in the base configuration no builtin applications are selected. NOTES: 1. This configuration uses the mconf-based configuration tool. To change this configuration 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. By default, this configuration uses the CodeSourcery toolchain for Windows and builds under Cygwin (or probably MSYS). That can easily be reconfigured, of course. CONFIG_HOST_LINUX=y : Linux (Cygwin under Windows okay too). CONFIG_ARMV7M_TOOLCHAIN_BUILDROOT=y : Buildroot (arm-nuttx-elf-gcc) CONFIG_RAW_BINARY=y : Output formats: ELF and raw binary