Need help on connecting an I/O pin to an external device

[Leo]

Hi,

I need to connect my microcontroller to operate an external DC motor (a back EMF is obviously expected).
At the moment I use relays, but I have seen that my system reset few times with the relay pickup.

Do you have any quick idea with your experience?

Best Regards,

Leo

[Magneto]

Hi Friend,

When you use a Relay with a microcontroller , put a diode inbetween the two terminal of relay coil. And this
diode should be reverse bias. This will eliminate the microcontroller restart problem.