This is small, lightweight Embedded OS for study
Target Board : STM32f4Discovery
GPIO, UART, Timer, ADC, PWM, Non-preemptive Scheduling, Round Robin, Synchronization(mutex, semaphore), Include Library
sudo vim .bashrc
add export PATH="[gcc arm/bin path]:$PATH"
make
find out.elf
sudo apt-get install openocd
program make flash