The input circuitry could still be damaged even if the output circuitry works to drive LEDs. It would unusual.
I would get a 5K or 10K pot with one end tied to 5V and the other to ground with the wiper tied to the I/O pin through a 220 ohm resistor, then see what range of settings causes the pin to read LOW and HIGH. The threshold should be pretty much the same as that of "normal" pins.
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- Stephen
I would get a 5K or 10K pot with one end tied to 5V and the other to ground with the wiper tied to the I/O pin through a 220 ohm resistor, then see what range of settings causes the pin to read LOW and HIGH. The threshold should be pretty much the same as that of "normal" pins.