I was trying to measure the PWM output on digital pin 5. accidentally i connected one of probes to pin 13 instead of ground pin. there must be approx 5 volts out on pin 5.
now there is no voltage on any digital out pins. there is voltage on TX pin and RX pin.
will multimeter damage digital outs this easily? i did not shot any pins directly.
If the meter is set to volts (or anything else then current), nope. It's just fine to measure the voltage between two pins, not a problem. Voltage has no notion of ground aka what you call 0V.
PS You can't measure the voltage on a PWM pin, at least not with a non-true RMS meter on AC. But even then, the output of a PWM pin isn't a voltage between 0 and 5V but a train of 5V pulses.
thanks for response. somehow mega decided to give output on digital pins in addition to tx and rx. i did not understand what was wrong. a glitch may be.