Can you destroy arduino using DMM to measure resistance? (Trying to figure out how did I broke my board)
Etwus:
Can you destroy arduino using DMM to measure resistance? (Trying to figure out how did I broke my board)
Was the Arduino powered at the time?
Paul
No, it was not.
No. Even powered-up it wouldn't hurt anything. You'd just get invalid readings.
But, a static discharge from you body could kill it.
A DMM in current-mode is a short-circuit and that blow-up powered circuits if you connect it incorrectly.
...I did have an Arduino die "for no reason" once, and I assume that was static discharge. (You don't have to feel a spark.) I try to ground myself before touching any electronics, but at home I don't use a proper ground strap.
At work, we are required to wear ground-straps on our wrists or we have foot-straps and the floors are coated with conductive wax. All of our workbenches have grounded anti-static mats, etc.
What "resistance" on the Arduino were you trying to measure, and how?
It is possible that a DMM on resistance range could destroy an input, if a voltage > Vcc + 0.5 V is applied. The damage would depend on the current flow.
jremington:
What "resistance" on the Arduino were you trying to measure, and how?It is possible that a DMM on resistance range could destroy an input, if a voltage > 5.5 V is applied. The damage would depend on the current flow.
From continuity test (200ohm) to 200Mohm. I measured it between some random pins. Not sure what voltage does my multimeter (FK64L) use.
As DVDdoug said, it is probably esd damage. It works, but behaviour is totally random. My blink every 100 ms program sometimes works for 1 to 3 seconds, then nothing. Reset is doing nothing. Strange.
You need another multimeter to check the voltage used by the continuity or resistance range.
ESD damage is certainly possible, but wobbly connections are also a possibility.
Etwus:
As DVDdoug said, it is probably esd damage. It works, but behaviour is totally random. My blink every 100 ms program sometimes works for 1 to 3 seconds, then nothing. Reset is doing nothing. Strange.
When your blink program stops working, can you tell us what do you do to restart it?
When the program stops working, can you use your meter to check the voltage powering your Arduino? Is it about right?
You could have some kind of exotic (or not so exotic 
software problem causing this.
A DMM set to resistance outputs a current limited measuring voltage.
My meters output 3volt with a max current of 1mA on diode test.
I doubt that that, or any other resistance range, could kill an Arduino Uno/Nano/Mega.
ESD can indeed kill electronics.
You should touch (finger, instruments) ground of the Arduino (metal of USB socket) before handling/measuring.
Leo..
My meters output 3volt with a max current of 1mA on diode test.
I doubt that that, or any other resistance range, could kill an Arduino Uno/Nano/Mega.
Good to know! The OP can eliminate your DMM as a possible source of the problem.
I think 3volt is typical for a DMM, but YOU and OP can measure that resistance measuring voltage with a second DMM set to voltage.
You SHOULD know all the quirks of YOUR measuring gear before relying on it.
Leo..
A good DMM would not output enough current or voltage to damage electronics (except perhaps some
of the more exotic microwave devices which are extremely sensitive). Some random cheap
continuity tester I would not trust however.
Etwus:
Can you destroy arduino using DMM to measure resistance? (Trying to figure out how did I broke my board)
Perhaps unlikely. On the other hand, if the DMM has failed somehow --- eg. shorted, then that could be a problem. But let's assume the DMM is fine. Another possibility could be whether or not the DMM was set to some other mode, other than 'resistance measurement' mode. Another possibilility --- the arduino just failed for unknown reason. So having spares should allow you to get going again. And, if you're concerned that a particular resistance measurement might have caused the issue ...... then set the DMM to resistance reading mode (double check on it), then repeat what you did before the failure (one the new arduino). If no problem, then the resistance measurement wasn't the issue.
MarkT:
A good DMM would not output enough current or voltage to damage electronics (except perhaps some
of the more exotic microwave devices which are extremely sensitive). Some random cheap
continuity tester I would not trust however.
I've had little problem over many years of playing with 'ordinary' semiconductors through ESD damage - but you're quite right.
A lot of uwave GaAs devices are both sensitive and expensive, so I take care!
Allan