hello, I'm building a stopwatch for my kart, I use a magnetic sensor and it looks it works fine.
I use a Nano and a 5110 screen: I used it and it was marvelous, but the other day I read that the 5110 can be retroilluminated if connected the LED pin to the 3.3v ( I never new this!).
so I take another nano, I connect it to the usb (also tried with the 9v battery), with a Dupont I connect the 3.3 to the LED (in my case the 8th hole): it lights on very brightly! so happy I go to my other nano (the one I use for the project) and see that the 3.3v is already used for the VCC hole on the 5110. then I just think to make a bridge and connect both the VCC and the LED to the 3.3v.
That's when the bad happens: the stopwatch stops working, but when I press the reset button it starts back on. the screen is not lighted, so I unplug everything and connect only the LED to the 3.3v, but nothing happens anymore!
I then try to change both the Nano and the 5110, plug the LED to the 3.3v and it works. try the bridge with both the LED and the VCC, and happens the same as before: stopwatch stops working and the screen doesn't light on.
what have I done? is there a way I can solve this?