13.3.2.1 Reset Sources

There are two kinds of sources for Resets:
  • Power supply Resets, which are caused by changes in the power supply voltage: Power-on Reset (POR) and Brown-out Detector (BOD).
  • User Resets, which are issued by the application, by the debug operation, or by pin changes (Software Reset, Watchdog Reset, UPDI Reset, and external Reset pin RESET).