19.3.1 Initialization

The BOD settings are loaded from fuses during Reset. The BOD level and operating mode in Active mode and Idle sleep modes are set by fuses and cannot be changed by software. However, the operating mode in Standby and Power-Down sleep modes is also loaded from the fuses but can be modified by software.

Write a ‘1’ to the VLM Interrupt Enable (VLMIE) bit in the Interrupt Control (BOD.INTCTRL) register to enable the Voltage Level Monitor function. The VLM interrupt is configured by writing the VLM Configuration (VLMCFG) bits in BOD.INTCTRL. An interrupt is requested when the supply voltage crosses the VLM threshold from either above or below the threshold.

The VLM functionality will follow the BOD mode. If the BOD is disabled, the VLM will not be enabled, even if the VLMIE is ‘1’. If the BOD is using the Sampled mode, the VLM will also be sampled. The VLM threshold is defined by writing the VLM Level (VLMLVL) bits in the VLM Control (BOD.VLMCTRLA) register.