README ====== README for NuttX port to the Tiva TM4C123G LaunchPad. The Tiva TM4C123G LaunchPad Evaluation Board is a low-cost evaluation platform for ARM® Cortex™-M4F-based microcontrollers from Texas Instruments. Contents ======== On-Board GPIO Usage LEDs Serial Console USB Device Controller Functions AT24 Serial EEPROM I2C Tool Using OpenOCD and GDB with an FT2232 JTAG emulator TM4C123G LaunchPad Configuration Options MCP2515 - SPI - CAN Configurations On-Board GPIO Usage =================== PIN SIGNAL(S) LanchPad Function --- ---------------------------------------- --------------------------------------- 17 PA0/U0RX DEBUG/VCOM, Virtual COM port receive 18 PA1/U0TX DEBUG/VCOM, Virtual COM port transmit 19 PA2/SSIOCLK GPIO, J2 pin 10 20 PA3/SSIOFSS GPIO, J2 pin 9 21 PA4/SSIORX GPIO, J2 pin 8 22 PA5/SSIOTX GPIO, J1 pin 8 23 PA6/I2CLSCL GPIO, J1 pin 9 24 PA7/I2CLSDA GPIO, J1 pin 10 45 PB0/T2CCP0/U1Rx GPIO, J1 pin 3 46 PB1/T2CCP1/U1Tx GPIO, J1 pin 4 47 PB2/I2C0SCL/T3CCP0 GPIO, J2 pin 2 48 PB3/I2C0SDA/T3CCP1 GPIO, J4 pin 3 58 PB4/AIN10/CAN0Rx/SSI2CLK/T1CCP0 GPIO, J1 pin 7 57 PB5/AIN11/CAN0Tx/SSI2FSS/T1CCP1 GPIO, J1 pin 2 01 PB6/SSI2RX/T0CCP0 Connects to PD0 via resistor, GPIO, J2 pin 7 04 PB7/SSI2TX/T0CCP1 Connects to PD1 via resistor, GPIO, J2 pin 6 52 PC0/SWCLK/T4CCP0/TCK DEBUG/VCOM 51 PC1/SWDIO/T4CCP1/TMS DEBUG/VCOM 50 PC2/T5CCP0/TDI DEBUG/VCOM 49 PC3/SWO/T5CCP1/TDO DEBUG/VCOM 16 PC4/C1-/U1RTS/U1RX/U4RX/WT0CCP0 GPIO, J4 pin 4 15 PC5/C1+/U1CTS/U1TX/U4TX/WT0CCP1 GPIO, J4 pin 5 14 PC6/C0+/U3RX/WT1CCP0 GPIO, J4 pin 6 13 PC7/C0-/U3TX/WT1CCP1 GPIO, J4 pin 7 61 PD0/AIN7/I2C3SCL/SSI1CLK/SSI3CLKWT2CCP0 Connects to PB6 via resistor, GPIO, J3 pin 3 62 PD1/AIN6/I2C3SDA/SSI1Fss/SSI3Fss/WT2CCP1 Connects to PB7 via resistor, GPIO, J3 Pin 4 63 PD2/AIN5/SSI1RX/SSI3RX/WT3CCP0 GPIO, J3 pin 5 64 PD3/AIN4/SSI1TX/SSI3TX/WT3CCP1 GPIO, J3 pin 6 43 PD4/U6RX/USB0DM/WT4CCP0 USB_DM 44 PD5/U6TX/USB0DP/WT4CCP1 USB_DP 53 PD6/U2RX/WT5CCP0 GPIO, J4 pin 8 10 PD7/NMI/U2TX/WT5CCP1 +USB_VBUS, GPIO, J4 pin 9 Used for VBUS detection when configured as a self-powered USB Device 09 PE0/AIN3/U7RX GPIO, J2 pin 3 08 PE1/AIN2/U7TX GPIO, J3 pin 7 07 PE2/AIN1 GPIO, J3 pin 8 06 PE3/AIN0 GPIO, J3 pin 9 59 PE4/AIN9/CAN0RX/I2C2SCL/U5RX GPIO, J1 pin 5 60 PE5/AIN8/CAN0TX/I2C2SDA/U5TX GPIO, J1 pin 6 28 PF0/C0O/CAN0RX/NMI/SSI1RX/T0CCP0/U1RTS USR_SW2 (Low when pressed), GPIO, J2 pin 4 29 PF1/C1O/SSI1TX/T0CCP1/TRD1/U1CTS LED_R, GPIO, J3 pin 10 30 PF2/SSI1CLK/T1CCP0/TRD0 LED_B, GPIO, J4 pin 1 31 PF3/CAN0TX/SSI1FSS/T1CCP1/TRCLK LED_G, GPIO, J4 pin 2 05 PF4/T2CCP0 USR_SW1 (Low when pressed), GPIO, J4 pin 10 AT24 Serial EEPROM ================== AT24 Connections ---------------- A AT24C512 Serial EEPPROM was used for tested I2C. There are no I2C devices on-board the Launchpad, but an external serial EEPROM module module was used. The Serial EEPROM was mounted on an external adaptor board and connected to the LaunchPad thusly: - VCC J1 pin 1 3.3V J3 pin 1 5.0V - GND J2 pin 1 GND J3 pin 2 GND - PB2 J2 pin 2 SCL - PB3 J4 pin 3 SDA Configuration Settings ---------------------- The following configuration settings were used: System Type -> Tiva/Stellaris Peripheral Support CONFIG_TIVA_I2C0=y : Enable I2C System Type -> I2C device driver options TIVA_I2C_FREQUENCY=100000 : Select an I2C frequency Device Drivers -> I2C Driver Support CONFIG_I2C=y : Enable I2C support Device Drivers -> Memory Technology Device (MTD) Support CONFIG_MTD=y : Enable MTD support CONFIG_MTD_AT24XX=y : Enable the AT24 driver CONFIG_AT24XX_SIZE=512 : Specifies the AT 24C512 part CONFIG_AT24XX_ADDR=0x53 : AT24 I2C address Application Configuration -> NSH Library CONFIG_NSH_ARCHINIT=y : NSH board-initialization File systems CONFIG_NXFFS=y : Enables the NXFFS file system CONFIG_NXFFS_PREALLOCATED=y : Required : Other defaults are probably OK Board Selection CONFIG_TM4C123G_LAUNCHPAD_AT24_BLOCKMOUNT=y : Mounts AT24 for NSH CONFIG_TM4C123G_LAUNCHPAD_AT24_NXFFS=y : Mount the AT24 using NXFFS You can then format the AT24 EEPROM for a FAT file system and mount the file system at /mnt/at24 using these NSH commands: nsh> mkfatfs /dev/mtdblock0 nsh> mount -t vfat /dev/mtdblock0 /mnt/at24 Then you an use the FLASH as a normal FAT file system: nsh> echo "This is a test" >/mnt/at24/atest.txt nsh> ls -l /mnt/at24 /mnt/at24: -rw-rw-rw- 16 atest.txt nsh> cat /mnt/at24/atest.txt This is a test STATUS: 2014-12-12: I was unsuccessful getting my AT24 module to work on the TM4C123G LaunchPad. I was unable to successuflly communication with the AT24 via I2C. I did verify I2C using the I2C tool and other I2C devices and I now believe that my AT24 module is not fully functional. I2C Tool ======== I2C Tool. NuttX supports an I2C tool at apps/system/i2c that can be used to peek and poke I2C devices. That tool can be enabled by setting the following: System Type -> TIVA Peripheral Support CONFIG_TIVA_I2C0=y : Enable I2C0 CONFIG_TIVA_I2C1=y : Enable I2C1 CONFIG_TIVA_I2C2=y : Enable I2C2 ... System Type -> I2C device driver options CONFIG_TIVA_I2C0_FREQUENCY=100000 : Select an I2C0 frequency CONFIG_TIVA_I2C1_FREQUENCY=100000 : Select an I2C1 frequency CONFIG_TIVA_I2C2_FREQUENCY=100000 : Select an I2C2 frequency ... Device Drivers -> I2C Driver Support CONFIG_I2C=y : Enable I2C support Application Configuration -> NSH Library CONFIG_SYSTEM_I2CTOOL=y : Enable the I2C tool CONFIG_I2CTOOL_MINBUS=0 : I2C0 has the minimum bus number 0 CONFIG_I2CTOOL_MAXBUS=2 : I2C2 has the maximum bus number 2 CONFIG_I2CTOOL_DEFFREQ=100000 : Pick a consistent frequency The I2C tool has extensive help that can be accessed as follows: nsh> i2c help Usage: i2c [arguments] Where is one of: Show help : ? List buses : bus List devices : dev [OPTIONS] Read register : get [OPTIONS] [] Show help : help Write register: set [OPTIONS] [] Verify access : verf [OPTIONS] [] [] Where common "sticky" OPTIONS include: [-a addr] is the I2C device address (hex). Default: 03 Current: 03 [-b bus] is the I2C bus number (decimal). Default: 0 Current: 0 [-r regaddr] is the I2C device register address (hex). Default: 00 Current: 00 [-w width] is the data width (8 or 16 decimal). Default: 8 Current: 8 [-s|n], send/don't send start between command and data. Default: -n Current: -n [-i|j], Auto increment|don't increment regaddr on repititions. Default: NO Current: NO [-f freq] I2C frequency. Default: 100000 Current: 100000 NOTES: o Arguments are "sticky". For example, once the I2C address is specified, that address will be re-used until it is changed. WARNING: o The I2C dev command may have bad side effects on your I2C devices. Use only at your own risk. As an example, the I2C dev command can be used to list all devices responding on I2C0 (the default) like this: nsh> i2c dev 0x03 0x77 0 1 2 3 4 5 6 7 8 9 a b c d e f 00: -- -- -- -- -- -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- 1a -- -- -- -- -- 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 30: -- -- -- -- -- -- -- -- -- 39 -- -- -- 3d -- -- 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: 60 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- -- nsh> NOTE: This is output from a different board and shows I2C devices responding at addresses 0x1a, 0x39, 0x3d, and 0x60. Using OpenOCD and GDB with an FT2232 JTAG emulator ================================================== Building OpenOCD under Cygwin: Refer to boards/arm/lpc17xx_40xx/olimex-lpc1766stk/README.txt Installing OpenOCD in Linux: sudo apt-get install openocd As of this writing, there is no support for the tm4c123g in the package above. You will have to build openocd from its source (as of this writing the latest commit was b9b4bd1a6410ff1b2885d9c2abe16a4ae7cb885f): git clone http://git.code.sf.net/p/openocd/code openocd cd openocd Then, add the patches provided by http://openocd.zylin.com/922: git fetch http://openocd.zylin.com/openocd refs/changes/22/922/14 && git checkout FETCH_HEAD ./bootstrap ./configure --enable-maintainer-mode --enable-ti-icdi make sudo make install For additional help, see http://processors.wiki.ti.com/index.php/Tiva_Launchpad_with_OpenOCD_and_Linux 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: boards/arm/tiva/tm4c123g-launchpad/tools/tm4c123g-launchpad.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 tm4c123g-launchpad.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/ek-tm4c123gxl.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 boards/arm/tiva/tm4c123g-launchpad/tools/tm4c123g-launchpad.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: boards/arm/tiva/tm4c123g-launchpad/tools. You may want to add that path to your PATH variable. 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'. LEDs ==== The TM4C123G has a single RGB LED. If CONFIG_ARCH_LEDS is defined, then support for the LaunchPad LEDs will be included in the build. See: - boards/arm/tiva/tm4c123g-launchpad/include/board.h - Defines LED constants, types and prototypes the LED interface functions. - boards/arm/tiva/tm4c123g-launchpad/src/tm4c123g-launchpad.h - GPIO settings for the LEDs. - boards/arm/tiva/tm4c123g-launchpad/src/up_leds.c - LED control logic. OFF: - OFF means that the OS is still initializing. Initialization is very fast so if you see this at all, it probably means that the system is hanging up somewhere in the initialization phases. GREEN or GREEN-ish - This means that the OS completed initialization. Bluish: - Whenever and interrupt or signal handler is entered, the BLUE LED is illuminated and extinguished when the interrupt or signal handler exits. This will add a BLUE-ish tinge to the LED. Redish: - If a recovered assertion occurs, the RED component will be illuminated briefly while the assertion is handled. You will probably never see this. Flashing RED: - In the event of a fatal crash, the BLUE and GREEN components will be extinguished and the RED component will FLASH at a 2Hz rate. Serial Console ============== By default, all configurations use UART0 which connects to the USB VCOM on the DEBUG port on the TM4C123G LaunchPad: UART0 RX - PA.0 UART0 TX - PA.1 However, if you use an external RS232 driver, then other options are available. UART1 has option pin settings and flow control capabilities that are not available with the other UARTS:: UART1 RX - PB.0 or PC.4 (Need disambiguation in board.h) UART1 TX - PB.1 or PC.5 (" " " " "" " ") UART1_RTS - PF.0 or PC.4 UART1_CTS - PF.1 or PC.5 NOTE: board.h currently selects PB.0, PB.1, PF.0 and PF.1 for UART1, but that can be changed by editing board.h UART2-5, 7 are also available, UART2 is not recommended because it shares some pin usage with USB device mode. UART6 is not available because its only RX/TX pin options are dedicated to USB support. UART2 RX - PD.6 UART2 TX - PD.7 (Also used for USB VBUS detection) UART3 RX - PC.6 UART3 TX - PC.7 UART4 RX - PC.4 UART4 TX - PC.5 UART5 RX - PE.4 UART5 TX - PE.5 UART6 RX - PD.4, Not available. Dedicated for USB_DM UART6 TX - PD.5, Not available. Dedicated for USB_DP UART7 RX - PE.0 UART7 TX - PE.1 USB Device Controller Functions =============================== Device Overview An FT2232 device from Future Technology Devices International Ltd manages USB-to-serial conversion. The FT2232 is factory configured by Luminary Micro to implement a JTAG/SWD port (synchronous serial) on channel A and a Virtual COM Port (VCP) on channel B. This feature allows two simultaneous communications links between the host computer and the target device using a single USB cable. Separate Windows drivers for each function are provided on the Documentation and Software CD. Debugging with JTAG/SWD The FT2232 USB device performs JTAG/SWD serial operations under the control of the debugger or the Luminary Flash Programmer. It also operate as an In-Circuit Debugger Interface (ICDI), allowing debugging of any external target board. Debugging modes: MODE DEBUG FUNCTION USE SELECTED BY 1 Internal ICDI Debug on-board TM4C123G Default Mode microcontroller over USB interface. 2 ICDI out to JTAG/SWD The EVB is used as a USB Connecting to an external header to SWD/JTAG interface to target and starting debug an external target. software. The red Debug Out LED will be ON. 3 In from JTAG/SWD For users who prefer an Connecting an external header external debug interface debugger to the JTAG/SWD (ULINK, JLINK, etc.) with header. the EVB. Virtual COM Port The Virtual COM Port (VCP) allows Windows applications (such as HyperTerminal) to communicate with UART0 on the TM4C123G over USB. Once the FT2232 VCP driver is installed, Windows assigns a COM port number to the VCP channel. MCP2515 - SPI - CAN =================== I like CANbus, and having an MCP2515 CAN Bus Module laying around gave me the idea to implement it on the TM4C123GXL (Launchpad). Nuttx already had implemented it on the STM32. So a lot of work already has been done. It uses SPI and with this Launchpad we use SSI. Here is how I have the MCP2515 Module connected. But you can change this with the settings in include/board.h and src/tm4c123g-launchpad.h. Connector pinout that I am using: --------------------------+---------------------------------------------- Connector CAN Module | Launchpad TM4C123GXL (SSI2_1) --------------------------+---------------------------------------------- 1 INT | PB0 2 SCK | PB4 (Clock) 3 SI | PB7 (MOSI = TX) 4 SO | PB6 (MISO = RX) 5 CS | PB5 (Chip Select) 6 GND | GND 7 VCC | VBUS (+5V) --------------------------+---------------------------------------------- PS: I have to test the CS signal when adding it on a bus with multiple nodes. TM4C123G LaunchPad 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_TM4C123GH6PM CONFIG_ARCH_BOARD - Identifies the boards/ subdirectory and hence, the board that supports the particular chip or SoC. CONFIG_ARCH_BOARD=tm4c123g-launchpad (for the TM4C123G LaunchPad) CONFIG_ARCH_BOARD_name - For use in C code CONFIG_ARCH_BOARD_TM4C123G_LAUNCHPAD 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. 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 TM4C123G 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 TM4C123G LaunchPad configuration is maintained in a sub-directory of boards/arm/tiva/tm4c123g-launchpad/configs/ and can be selected as follows: tools/configure.sh tm4c123g-launchpad: Where is one of the following: mcp2515 ======= Configuration uses the MCP2515 SPI CAN part. See the section entitled "MCP2515 - SPI - CAN" above. 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 see additional README.txt files in the NuttX tools repository. b. Execute 'make menuconfig' in nuttx/ in order to start the reconfiguration process. 2. By default, this configuration uses the ARM EABI 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