11.3.4 JTAG (mega) Related

When target power is lost, restored, or an external reset is applied, some spurious event messages may appear

For projects containing self modifying code: When uploading a project, the target AVR enters RUN mode for some milliseconds before resetting to the reset vector. This means that the target application may have altered the state of the target Atmel AVR Flash and EEPROM. Workaround: The application must be written so that the self modifying code is not unintentionally accessed.