?????????????STM32???
???????STM32??5??????HSI??HSE??LSI??LSE??PLL????????????????????????п??????PLL??????HSI??HSE?????
???У????????(HSE??HSI)????о???????????.???????(LSE??LSI)???????о??е?RTC(?????)?????????????????п??????????????????????RTC????????????о????RC??????????????????????????о?????????????????????????????????????????????????????????????????????к??????????????????????????????????????????????????.
?????????(HSE)?????????????????????????????Χ?4~16MHz????????????8MHz?????
??????????(HSI)?? ?????RC??????????????8MHz???????????
?????????(LSE)????????????????????????????????飬??????????32.768KHz??
??????????(LSI)???????RC?????????????????????????飬??????40KHz??
OSC_OUT??OSC_IN?????????????????????????8MHz,??????????PLLXTPRE??????????PLLSRC(PLL entry clock source)????????????????????????????????(HSE)??????????????(HSI)?????????????HSE??????????????PLL?????б?????????????????????????????PLLMUL??????????????????????????????????????PLL???????PLLCLK??????????????趨?9?????????????????PLL???????????????8MHz?? HSE???72MHz??PLLCLK???????????????????????SW???????????????????STM32???????(SYSCLK)???????????????????л?SYSCLK????????????
????HSI??PLLCLK??HSE??????????PLLCLK????????SYSCLK???72MHz???PLLCLK??????SW???????????USB????????????????????USB????????(USBCLK)?????SYSCLK??SYSCLK????AHB??????????????????????????衣??????????HCLK??FCLK????????????????SDIO?????
SDIOCLK?????洢????????FSMC??FSMCCLK?????????APB1??APB2????????????????GPIO?????ǹ?????APB2???????? APB2???????APB2???????????????APB2????????????????AHB??????????????APB2???????????????????????????????GPIO?????????????HCLK???72MHz???
SYSCLK????????STM32??????????????????????AHB????????????????????
HCLK:??AHB????????????????????????????AHB??????????????洢????DMA??cortex??????cortex??????е?????cpu???????????????????С??STM32?????????????????????????
FCLK???????AHB????????????????????????????????????????ɡ?????????????????? HCLK???????HCLK?????? FCLK ????????С?????????????????????????????????????????ж???????????? ??????HCLK?????????
PCLK1????????????APB1?????????????????????36MHz????????????APB1??????????裬APB1????????????????
RCC_APB1Periph_TIM2 TIM2???
RCC_APB1Periph_TIM3 TIM3???
RCC_APB1Periph_TIM4 TIM4???
RCC_APB1Periph_WWDG WWDG???
RCC_APB1Periph_SPI2 SPI2???
RCC_APB1Periph_USART2 USART2???
RCC_APB1Periph_USART3 USART3???
RCC_APB1Periph_I2C1 I2C1???
RCC_APB1Periph_I2C2 I2C2???
RCC_APB1Periph_USB USB???
RCC_APB1Periph_CAN CAN???
RCC_APB1Periph_BKP BKP???
RCC_APB1Periph_PWR PWR???
RCC_APB1Periph_ALL ???APB1???????
PCLK2????????????APB2??????????????????????72MHz????????????APB2??????????裬APB2????????????????
RCC_APB2Periph_AFIO ???????IO???
RCC_APB2Periph_GPIOA GPIOA???
RCC_APB2Periph_GPIOB GPIOB???
RCC_APB2Periph_GPIOC GPIOC???
RCC_APB2Periph_GPIOD GPIOD???
RCC_APB2Periph_GPIOE GPIOE???
RCC_APB2Periph_ADC1 ADC1???
RCC_APB2Periph_ADC2 ADC2???
RCC_APB2Periph_TIM1 TIM1???
RCC_APB2Periph_SPI1 SPI1???
RCC_APB2Periph_USART1 USART1???
RCC_APB2Periph_ALL ???APB2???????
????admin ?????????2018-05-23
