For starters, I'm completely new to all of this and am learning under only the guidance of the internet (this is for work). I'm trying to set up a reed switch on an Arduino Uno to make a bike speedometer. I originally hooked everything up to a bread board and it all worked fine. Then I attempted to set up a Proto Shield and move everything over to that so it would all fit in an enclosure. After putting everything back together, I turned the Arduino on, and the LCD lit up but it wasn't displaying anything. My first thought was that the contrast was to low which had been the problem the first time I set up the LCD, but when I adjust the potentiometer the display doesn't change at all until it's turned past a certain point when the LCD appears to shut off completely. It seems as if I've somehow made the potentiometer act as an on/off switch for the LCD, and I have not the slightest idea how. Does it have to do with how I've set up the Proto Shield, or is it something to do with the wiring?
I've attached a photo of my project minus the reed switch, but that's simple to hook up. Thanks for the help!
The Orange wire for contrast should be attached to the center pin / wiper of the potentiometer.
Your picture shows a yellow wire going to Gnd on the center pin, which then shorts to the 5v line as you rotate the pot.
So if you swap the yellow and orange wires around is should work.
Marsha
I switched the wires and the screen doesn't shut off anymore when I move the potentiometer, but the contrast still isn't adjusting. I think the problem may be my soldering.