teensy cmake macros

minimal dependency cmake toolchain to easily compile your teensy sketches and libraries, and optionally link with c++ std libraries.

• custom teensy toolchain using cmake and arm-none-eabi-gcc
• based on ronj/teensy-cmake-template
• targetting Teensy 4.x, tested on Teensy 4.1 (should be easy to extend for 3.x)
• compiles library code to .a archive files to avoid unnecessary recompiling

Usage

• add a toolchain cmake file cmake\toolchains\teensy41.cmake
  • update COMPILERPATH to arm-none-eabi-gcc bin folder

  set(TEENSY_VERSION 41 CACHE STRING "Set to the Teensy version corresponding to your board (30 or 31 allowed)" FORCE)
  set(CPU_CORE_SPEED 600000000 CACHE STRING "Set to 24000000, 48000000, 72000000 or 96000000 to set CPU core speed" FORCE) # Derived variables
  set(CMAKE_EXE_LINKER_FLAGS "--specs=nosys.specs" CACHE INTERNAL "")
  # set(CMAKE_EXE_LINKER_FLAGS "--specs=nano.specs" CACHE INTERNAL "") # if you plan on using std 
  
  #teensy compiler options
  set(COMPILERPATH "/Applications/ARM/bin/")
  
  set(BUILD_FOR_TEENSY ON)
  set(CMAKE_SYSTEM_NAME Generic)
  set(CMAKE_SYSTEM_PROCESSOR arm)
  set(CMAKE_TRY_COMPILE_TARGET_TYPE "STATIC_LIBRARY")
  set(CMAKE_C_COMPILER ${COMPILERPATH}arm-none-eabi-gcc)
  set(CMAKE_CXX_COMPILER ${COMPILERPATH}arm-none-eabi-g++)
  set(CMAKE_CXX_LINK_EXECUTABLE "${CMAKE_C_COMPILER} <FLAGS> <CMAKE_CXX_LINK_FLAGS> <LINK_FLAGS> <OBJECTS> -o <TARGET> <LINK_LIBRARIES>")

  • add include in your CMakeLists.txt file

    include(FetchContent)
    FetchContent_Declare(teensy_cmake_macros
        GIT_REPOSITORY https://github.com/newdigate/teensy-cmake-macros
        GIT_TAG        main
    )
    FetchContent_MakeAvailable(teensy_cmake_macros)
    include(${teensy_cmake_macros_SOURCE_DIR}/CMakeLists.include.txt)

• specify toolchain file in cmake configuration stage

  > cmake .. -DCMAKE_BUILD_TYPE=Release -DCMAKE_TOOLCHAIN_FILE:FILEPATH="../cmake/toolchains/teensy41.cmake`

install build dependencies

• arm-none-eabi-gcc
• cmake

add CMakeLists.txt to your project root

• create a CMakeLists.txt file in the root directory of your project

  cmake_minimum_required(VERSION 3.5)
  project(midi_smf_reader C CXX)

  include(FetchContent)
  FetchContent_Declare(teensy_cmake_macros
          GIT_REPOSITORY https://github.com/newdigate/teensy-cmake-macros
          GIT_TAG        main
  )
  FetchContent_MakeAvailable(teensy_cmake_macros)
  include(${teensy_cmake_macros_SOURCE_DIR}/CMakeLists.include.txt)

  import_arduino_library(cores ${teensy_cores_SOURCE_DIR}/teensy4 avr util)
  
  import_arduino_library_git(SPI https://github.com/PaulStoffregen/SPI.git master "")
  import_arduino_library_git(SdFat https://github.com/PaulStoffregen/SdFat.git master "src" common DigitalIO ExFatLib FatLib FsLib iostream SdCard SpiDriver)
  import_arduino_library_git(SD https://github.com/PaulStoffregen/SD.git Juse_Use_SdFat src)
  import_arduino_library_git(Encoder https://github.com/PaulStoffregen/Encoder.git master "")
  import_arduino_library_git(Bounce2 https://github.com/PaulStoffregen/Bounce2.git master src)
  import_arduino_library_git(SerialFlash https://github.com/PaulStoffregen/SerialFlash.git master "" util)
  import_arduino_library_git(Wire https://github.com/PaulStoffregen/Wire.git master "" utility)
  import_arduino_library_git(arm_math https://github.com/PaulStoffregen/arm_math.git master src)
  import_arduino_library_git(TeensyGFX https://github.com/newdigate/teensy-gfx.git main src)

  # add custom library
  teensy_add_library(my_teensy_library my_teensy_library.cpp)

  # add custom executable
  teensy_add_executable(my_firmware sketch.ino)
  teensy_target_link_libraries(my_firmware my_teensy_library SD SdFat SPI cores) # order is IMPORTANT because we are garbage collecting symbols --gc-collect
  
  # if you need to link to std library (using <Vector>, etc) 
  set(CMAKE_EXE_LINKER_FLAGS "--specs=nano.specs" CACHE INTERNAL "")
  target_link_libraries(my_firmware.elf stdc++)

build

• run from a terminal in your repository root directory

> mkdir cmake-build-debug
> cd cmake-build-debug
> cmake .. -DCMAKE_BUILD_TYPE=Debug -DCMAKE_TOOLCHAIN_FILE:FILEPATH="../cmake/toolchains/teensy41.toolchain.cmake" 
> make       

detail

• teensy_add_executable ( TARGET files... )

  teensy_add_executable(myapplication midiread.cpp)

• teensy_add_library ( TARGET files... )

  teensy_add_library(mylibrary library1.cpp)

• import_arduino_library ( LibraryName LibraryPath additionalRelativeSourceFolders)

  import_arduino_library(cores ${COREPATH} avr util)
  import_arduino_library(SPI ${DEPSPATH}/SPI)        # SPI@Juse_Use_SdFat
  import_arduino_library(SdFat ${DEPSPATH}/SdFat/src common DigitalIO ExFatLib FatLib FsLib iostream SdCard SpiDriver)
  import_arduino_library(SD ${DEPSPATH}/SD/src)  

• teensy_target_link_libraries ( TARGET libraries...)

  teensy_target_link_libraries(my_firmware mylibrary SD SdFat SPI cores)

• import_arduino_library_git ( LibraryName LibraryUrl Branch SourcePath additionalRelativeSourceFolders)

    import_arduino_library_git(SPI https://github.com/PaulStoffregen/SPI.git master "")
    import_arduino_library_git(SdFat https://github.com/PaulStoffregen/SdFat.git master "src" common DigitalIO ExFatLib FatLib FsLib iostream SdCard SpiDriver)
    import_arduino_library_git(SD https://github.com/PaulStoffregen/SD.git Juse_Use_SdFat src)
    import_arduino_library_git(Encoder https://github.com/PaulStoffregen/Encoder.git master "")
    import_arduino_library_git(Bounce2 https://github.com/PaulStoffregen/Bounce2.git master src)
    import_arduino_library_git(SerialFlash https://github.com/PaulStoffregen/SerialFlash.git master "" util)
    import_arduino_library_git(Wire https://github.com/PaulStoffregen/Wire.git master "" utility)
    import_arduino_library_git(arm_math https://github.com/PaulStoffregen/arm_math.git master src)
    import_arduino_library_git(TeensyGFX https://github.com/newdigate/teensy-gfx.git main src)

• link to std library

   set(CMAKE_EXE_LINKER_FLAGS "--specs=nano.specs" CACHE INTERNAL "")
   target_link_libraries(my_firmware.elf stdc++)

• teensy_include_directories ( paths...)

  teensy_include_directories(../../src)

used in

• midi-smf-reader
• teensy-quencer