I am new to Arduino and am having a problem running a set of 30 RGBW LED's without being connected to the computer. I am using a 12V DC power source and the sketch is working when the USB is connected but stops working when I remove the USB. I have verified that the power cord is operational and have also attempted to use a 9V battery. Any ideas on what the problem is?
My crystal ball sees a blocking while(!Serial.available()) in setup().
I hope you're not powering the LEDs through the Arduino.
Post a diagram.
Leo..
Not even my Tarot cards are telling anything….