RCC Backup domain control register (RCC_BDCR) 备份域控制寄存器 Bit 16 BDRST: Backup domain software reset 备份域软件复位 Bit 15 RTCEN: RTC clock enable RTC 时钟使能 Bits 9:8 RTCSEL[1:0]: RTC clock source selection RTC 时钟源选择 Bit 3 LSEMOD: External low-speed oscillator bypass :外部...