A demo project of FreeRTOS running on a STM32F4 Discovery board.

first , you have to add two directories named "binary" and "build". $mkdir binary $mkdir build

then, change the compiler path in Makefile to match the path of your own compiler

1. A PC running Linux or Windows with Cygwin(not tested). A Mac is also fine with this example.
2. A STM32F4Discovery board.
3. A FT232RL USB to serial board which is recommended if there's no serial port on your computer.
4. USB Cable, Dupont Line and other tools.

The pre-built version of GNU Tools for ARM can be downloaded from its website. It's available for most systems. Follow the instructions in the readme file and installed the toolchain to your system. To verify your installation, simply type arm-none-eabi-gcc --version in your terminal, if everything goes right, you'll get output like this:

arm-none-eabi-gcc (GNU Tools for ARM Embedded Processors) 4.7.3 20130312 (release) [ARM/embedded-4_7-branch revision 196615]
Copyright (C) 2012 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Grab the official utility from ST website. Note that you should install the USB driver before install the st-util.

Clone this git, follow the instructions on that page and install st-util to your system.

The only thing you need to do is to edit the makefile and let it know your toolchain installation path. Change the TOOLCHARN_ROOT variable at the third line of makefile and point it to where you installed the toolchain. The you can simply type make and compile the example.

Connect your STM32F4Discovery with a USB cable. You can flash the binary into the board with this:

$ st-flash write binary/FreeRTOS.bin 0x8000000

The code is wrote directly into internal flash of STM32 processor and it starts to run after reset. To debug it, first start the GDB server:

$ st-util &

And then GDB:

$ arm-none-eabi-gdb binary/FreeRTOS.elf
(gdb) tar ext :4242
(gdb) b main
(gdb) c

You'll get breakpoint triggered at main function, and enjoy!