Hello,
I'm currently working on a (hopefully) mobile project that uses a 2x16 LCD display and the liquidCrystal library to run the display. I have the breadboard powered with a 9V battery wired to a LM7805 regulator with a 1N4001 diode and 10uF and 100uF filtering capacitors. It looks like this: Imgur: The magic of the Internet
Now, whenever I load any of the liquidCrystal sample programs, it won't work with the 5V regulator circuit I've got going, but will work with the arduino's 5V output. I've checked the regulator circuit and it delivers a constant 4.95V. Any kind of voltage issue I felt that I could handle with a potentiometer that I have hooked up to the display to act as contrast. Is there something going on here that I can't see? Please help!