Our teacher sayed that the Arduino Board will be damaged if we let it running for 4 hours because of a such timer ...
I didn't believe what he sayed and i need to know the truth of this information .
Thanks for help ...
There is no problem running Arduino for hours on end.
If you are using millis() or micros() then a little bit of proper coding will allow them both to work as intended also if that is the concern.
Thanks very much Sir. Well , i don't use millis() or micros() .
So you mean there is no problem if we put 9V DC to the arduino's Vin and we let it work for many hours ?? the arduino bord will not be damaged ?
I doubt any Arduino would run for many hours on a 9V battery, but that's not a problem related to the Arduino.
Little 9V square battery is good for 200-300mAH capacity.
Arduino could be drawing 30-50mA depending on what it is doing, how many LEDs are connected, yes.
4 hours with not much connected should be reachable.
Arduino will run until the battery dies.
If you are writing to EEPROM as the battery gets, might see some data corruption, or other odd effects from power being too low.