This is based on the cortex-m-quickstart project.
The code is for the stm32-f411re processor, and is meant for the nucleo-f411re board. Pressed the user b1 button on Pin GPIOC 17 (PC17) will cause the led on Pin GPIOA 5 (PA5) to light up. This example also illustrates how to check pin state in a loop and share that resource with the interrupt through a mutex.
I've included some resources that have helped me along the way.
