/phobos

Primary LanguageC

#PHOBOS The larger and innermost of the two natural satellites of Mars, Phobos is the embedded system that controls the gyroscopic balance assistance system.

Toolchain

To compile the code, use GNU ARM Embedded toolchain. The version used is 5.3-2016-q1.

Some examples may not build as the option -fsingle-precision-constant is not standard compliant. The issue is documented here and contains a fix.

As most computers will be running a 64-bit kernel, libraries for ia32/i386 architecture will need to be installed if not already. For recent versions of Ubuntu, this can be installed with the gcc-multilib package.

Building

When creating the CMake build tree, the compiler must be set to the target toolchain to allow cross-compilation. CMake cannot change the compiler after the build tree has been created and if the toolchain is not provided, the default compiler will be used. The path to the toolchain must be defined in a CMake script file and passed as in the argument CMAKE_TOOLCHAIN_FILE the first time cmake is called. An example file is provided in the root project directory.

oliver@canopus:~/repos/phobos$ mkdir build
oliver@canopus:~/repos/phobos$ cd build/
oliver@canopus:~/repos/phobos/build$ cmake -DCMAKE_TOOLCHAIN_FILE=~/toolchain/toolchain-gcc-arm-none-eabi-5_3-2016q1.cmake ..
oliver@canopus:~/repos/phobos/build$ make -j8

Build options can be passed as arguments to cmake or set with ccmake after the build tree has been created.

oliver@canopus:~/repos/phobos/build$ ccmake .

Flashing

The compiled ELF can be flashed to the microcontroller by enabling the OPENOCD_FLASH_TARGET or OPENOCD_FLASH_AND_RUN_TARGET CMake options.

If you are running OSX and unable to flash successfully with CMake, OpenOCD may be requesting to receive incoming network connections. This can be done by signing the application:

oliver@canopus:~$ codesign --verify -vv /usr/local/Cellar/open-ocd/HEAD/bin/openocd

In 'Security & Privacy', verify that the option 'Automatically allow signed software to receive incoming connections' is enabled.

Debugging

The microcontroller can be debugged with OpenOCD and GDB.

oliver@canopus:~/repos/phobos$ openocd -f openocd_olimex-arm-usb-tiny-h_stm32f4.cfg

In another shell instance, pass GDB the ELF as an argument

oliver@canopus:~/repos/phobos/build$ ~/toolchain/gcc-arm-none-eabi-5_3-2016q1/bin/arm-none-eabi-gdb demos/usb_serial/usb-serial.elf

To connect to target

(gdb) target extended-remote localhost:3333

Additionally, the ELF can be flashed

(gdb) load
(gdb) mon reset init

There is an example gdbinit file in the root directory that defines a command to connect to the remote and set hardware break/watch point limits in addition to disabling IRQs while stepping. This can be used by renaming the file to .gdbinit and placing in your home or project directory or by executing GDB commands from a file when starting GDB

oliver@canopus:~/repos/phobos/build$ ~/toolchain/gcc-arm-none-eabi-5_3-2016q1/bin/arm-none-eabi-gdb -x ../gdbinit demos/usb_serial/usb-serial.elf

Debugging with Eclipse

Eclipse can also be used for debugging and can be downloaded here. With the use of plugins, it is much easier to read register values and view thread status and stack usage.

For general instructions refer to the ChibiOS/Eclipse guides part 1 and part 2.

Project Setup

  • Install the Eclipse IDE for C/C++ Developers. You probably need the JDK which can be found here.
  • Create an Eclipse project with CMake: (don't include the linebreak)
    oliver@canopus:~/repos/phobos/build-eclipse$ cmake -G"Eclipse CDT4 - Unix Makefiles" -DCMAKE_TOOLCHAIN_FILE=../toolchain-gcc-arm-none-eabi-5_3-2016q1.cmake ..
    Don't forget to set build type to 'Debug' and enable ChibiOS debug options.
  • In Eclipse, import the project using 'File->Import'.
    Select 'General->Existing Projects into Workspace'.
    Set 'Select root directory:' to the previously used build directory and select the project.
  • In 'Project->Properties', 'C/C++ Make Project->Binary Parser', select 'GNU Elf Parser'.
  • OpenOCD can be configured as an external tool.
    Provide the location of the binary, set the working directory to be
    ${workspace_loc:/PHOBOS-Debug@build-eclipse} and set arguments to
    -f ../openocd_olimex-arm-usb-tiny-h_stm32f4.cfg

Plugin Setup

  • 'C/C++ GDB Hardware Debugging' can be found in the 'Mobile and Device Development' category of available software.
  • 'EmbSysRegView' can be found in 'Help->Eclipse Marketplace'.
  • Copy ChibiOS jar files found in eclipse/dropins to the Eclipse dropins directory. For OSX, this is located at /Applications/Eclipse.app/Contents/Eclipse/dropins/