STM32 System Clock and Delay Function Initialization
STM32 has three different clock sources that can be used to drive the system clock (SYSCLK): 1: HSI oscillator clock (internal clock) 2: HSE oscillator clock (external clock, provided by the crystal) 3: PLL clock (Phase-Locked Loop clock) These devices have the following two secondary clock sources: (1) 40kHz low-speed internal RC, which can be … Read more