系统时钟如下:
System Clock source = PLL (HSE BYPASS)
SYSCLK(Hz) = 400000000 (CPU Clock)
HCLK(Hz) = 200000000 (AXI and AHBs Clock)
AHB Prescaler = 2
D1 APB3 Prescaler = 2 (APB3 Clock 100MHz)
D2 APB1 Prescaler = 2 (APB1 Clock 100MHz)
D2 APB2 Prescaler = 2 (APB2 Clock 100MHz)
D3 APB4 Prescaler = 2 (APB4 Clock 100MHz)
因为APB1 prescaler != 1, 所以 APB1上的TIMxCLK = APB1 x 2 = 200MHz;
因为APB2 prescaler != 1, 所以 APB2上的TIMxCLK = APB2 x 2 = 200MHz;
APB4上面的TIMxCLK没有分频,所以就是100MHz;
APB1 定时器有 TIM2, TIM3 ,TIM4, TIM5, TIM6, TIM7, TIM12, TIM13, TIM14,LPTIM1
APB2 定时器有 TIM1, TIM8 ,TIM15, TIM16,TIM17
APB4 定时器有 LPTIM2,LPTIM3,LPTIM4,LPTIM5 |