Independent Watchdog | STM32F4 | IWDG | CMSIS
Independent Watchdog The independent watchdog is based on a 12-bit downcounter and 8-bit prescaler. It is clocked from an independent 32 kHz internal RC and as it operates independently from the main clock, it can operate in Stop and Standby modes. It can be used either as a watchdog to reset the device when a problem occurs or as a free-running timer for application timeout management. It is hardware- or software-configurable through the option bytes(extracted from the Datasheet). Read the presentation on the IWDG peripheral by STMicroelectronics. IWDG Registers The Independent Watchdog has few registers. They are IWDG Key Register (IWDG_KR) IWDG Prescaler Register (IWDG_PR) IWDG Reload Register (IWDG_RLR) IWDG Status Register (IWDG_SR) The Key register provides access protection to the Prescale Register and Reload Register. Writing 0x5555 to IWDG_KR enables write access to IWDG_PR and IWDG_RLR. Writing 0xAAAA loads the reload value stored in IWDG_RLR to the counter. Writing 0xCCCC e