STM32 System Initialization: void SystemInit(void)

This function is the initialization function for the system clock and other system settings. It sets the FPU settings, resets the RCC clock configuration, disables interrupts, configures the system clock source, PLL multipliers and dividers, AHB/APBx prescalers, and Flash settings. It also configures the vector table location and offset address. Additionally, if the macro 'DATA_IN_ExtSRAM' or 'DATA_IN_ExtSDRAM' is defined, it calls the SystemInit_ExtMemCtl() function to configure external memory settings.