See : C.M. Kormanyos, Real-Time C++: Efficient Object-Oriented and Template Microcontroller Programming, Third Edition (Springer, Heidelberg, 2018). ISBN 9783662567173
The reference application boots via a small startup code and subsequently initializes a skinny microcontroller abstraction layer (MCAL). Control is then passed to a simple multitasking scheduler that schedules the LED application, calls a cyclic a benchmark task, and services the watchdog. The LED application toggles a user-LED with a frequency of 1/2 Hz.
The reference application supports the following targets:
*nix-like generic host
The reference application uses cross-development based on
tools in combination with Microsoft(R) Visual Studio(R). Tool chains
are not available in this repo (see below for further details).
The ATMEL(R) AVR(R) Atmega328P configuration in the reference application also has a project workspace for ATMEL(R) Atmel Studio(R) 6.
It is easiest to get started with the reference application using one of the supported boards, such as Arduino or RaspberryPi or BeagleBone. etc. The reference application can be found in the directory ref_app and its subdirectories.
To get started with the reference application, start Visual Studio(R) 2017 (or later) and open the solution ref_app.sln. Select the desired configuration. Then rebuild the entire solution. Note that the build in Visual Studio(R) makes heavy use of cross development using a project workspace of type "external makefile" to invoke GNUmake (via batch file) in combination with several makefiles.
CMake files have also been created for each supported target.
To build any target other than Debug or Release for Win32, a cross-compiler (GNU GCC cross compiler) is required. See the text below for additional details.
Upon successful build, the build results, such as the HEX-files, map files, etc., will be placed in the bin directory.
There is also a workspace solution for ATMEL(R) Atmel Studio(R) 6. It is called ref_app.atsln.
Win+R, cmd, enter
If VS variable is not set by default (default install), open Visual Studio Build Window
cd real-time-cpp mkdir build cd build cmake ../ref_app -DTARGET=host cmake --build . --config Debug --target ALL_BUILD
*nix pattern to build with x86_64-w64-mingw32 from MSYS or Cygwin
should work too.
Target details including startup code and linker definition files can be found in the target-directory and its subdirectories.
The ATMEL(R) AVR(R) configuration runs on an Arduino(R) compatible board. The program toggles the yellow LED on portb.5.
The NXP(R) OM13093 LPC11C24 board ARM(R) Cortex(TM)-M0 configuration called "target lpc1124" toggles the LED on port0.8.
The ARM(R) Cortex(TM)-M3 configuration (called "target stm32f100") runs on the STM32VLDISCOVERY board commercially available from ST Microelectronics(R). The program toggles the blue LED on portc.8.
The second ARM(R) Cortex(TM)-M3 configuration (called "target stm32l100c") runs on the STM32L100 DISCOVERY board commercially available from ST Microelectronics(R). The program toggles the blue LED on portc.8.
The third ARM(R) Cortex(TM)-M3 configuration (called "target stm32l152") runs on the STM32L152C-DISCO board commercially available from ST Microelectronics(R). The program toggles the blue LED on portb.6.
The first ARM(R) Cortex(TM)-M4 configuration (called "target stm32f407") runs on the STM32F4DISCOVERY board commercially available from ST Microelectronics(R). The program toggles the blue LED on portd.15.
Another ARM(R) Cortex(TM)-M4 configuration (called "target stm32f446") runs on the STM32F446 Nucleo-64 board commercially available from ST Microelectronics(R). The program toggles the green LED on porta.5.
The ARM(R) A8 configuration (called "target am335x") runs on the BeagleBone
board (black edition). For the white edition, the CPU clock needs to be reduced
from 900MHz to something like 600MHz. This project creates a bare-metal program
for the BeagleBone that runs independently from any kind of
*nix distro on
the board. Our program is designed to boot the BeagleBone from a raw binary file
called "MLO" stored on a FAT32 SDHC microcard. The binary file includes a
special boot header comprised of two 32-bit integers. The program is loaded
from SD-card into RAM memory and subsequently executed. When switching on
the BeagleBone black, the boot button (S2) must be pressed while powering
up the board. The program toggles the first user LED (LED1 on port1.21).
The ARM(R) 11 configuration (called "target bcm2835_raspi_b") runs on the
RaspberryPi (PiZero) single core controller.
This project creates a bare-metal program for the PiZero.
This program runs independently from any kind of
*nix distro on the board.
Our program is designed to boot the PiZero from a raw binary file.
The raw binary file is called kernel.img and it is stored on a FAT32 SDHC
microcard. The program objcopy can be used to extract raw binary
from a ELF-file using the output flags
The kernel.img file is stored on the SD card together with
three other files: bootcode.bin, start.elf and (an optional)
config.txt, all described on internet. A complete set of
PiZero boot contents for an SD card
running the bare-metal reference application are included in this repo.
For other compatible boards, feel free contact me with an issue requesting further details on your desired target system.
GNU GCC cross compilers for the microcontroller solutions are not available here.
A GNU GCC port with a relatively high level of C++11 awareness such as GCC 4.8 or higher (better yet, GCC 4.9 or higher) is required for building the reference application.
Some of the code snippets demonstrate language elements not only from C++11, but also from C++14 and C++17. A compiler with C++17 support (such as GCC 7.2.0) can, therefore, be beneficial for success with all of the code snippets.
In the reference application, the makefiles are aware of a default location for the respective GCC tool chains. This location has been defined by me and it might not be where you want it to be. Therefore, when using the reference application or designing a custom build, the root directory of the tool chain must be properly supplied to the makefiles.