Absolute Maximum Ratings*
...
Voltage on any Pin except RESET
with respect to Ground ................................-0.5V to VCC + 0.5V*NOTICE: Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or other conditions beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
VCC with respect to GND is zero. The continuity and ohm meters very likely operate outside the -0.5 to +0.5 volt range.