Hello, I’ve been using my 16x2 Black on White LCD from Sparkfun for about a month now and it has been working great!
Then a few days ago I tried placing it on a breadboard and running it from and external power source instead of my Arduino (UNO).
The program wasn’t working quite right on it; the contrast wasn’t behaving like usual. I have been using a 10K potentiometer to control it and it had been working fine before. Now it won’t show anything until I turn it all the way to the right in which it then dimly displays the text, but it’s covered in only what I can describe as “gibberish”. From there I tried to simplify and I moved back to my other setup and tried just the “Hello World” example program. I have checked all the connections and everything is exactly as the original “Hello World” example program describes. Yet the same problem still occurred and I haven’t gotten any closer to figuring out why it’s happening. Please help me find out what’s wrong!