Stack vs heap
Heap is used by the operating system during dynamical allocation (when new is used).
If one wants to use a lot of dynamic allocations the Heap should be sufficiently big.
There are CPU and Interrupt vectors.
Do not assign decimal values to the registers.
RCC -> CR = 124; // Not intuitive
RCC->CR|=0b00000100; // Requires a lot of zeros
RCC->CR|=0x04; // Quite ok
RCC->CR|=(1<<2); // Shifting - the best way
RCC->CR|=(1<<2)|(1<<17); // Setting multiple bits
RCC->CR|=RCC_CR_HSION;
RCC->CR&=~RCC_CR_HSION;
Remember to run Kyle as an Administrator!