Hi everyone, i'm new of this forum. I've search if other posts can help me, but i can't find one so i'm asking you help.
I'm using an Arduino Uno with a 16x2 lcd. I charged my sketch and i works good (the strings start scrolling on the display from right to left only when i push a pushbutton), but when i unlink Arduino from Mac usb and link it to the electricity adaptor the strings go on loop like there's no pushbotton and also the led it's always turned on.
Why the pushbotton doesn't work with 9V electricity and works with usb?
Thanks for help
Here are the sketch