Arduino Mega Power Source Transition

Greetings everyone,

I have a program that I am running on my Arduino mega that works just fine when I have it plugged into my computer. Runs without any flaws and like it is supposed to. My problem is that when I go to plug my Arduino in via a 12V 1A outlet, it forgets the program I uploaded and then proceeds to perform the factory uploaded L light blinking. Oddly enough the On light blinks along with it. Does anyone have any ideas as to why my Arduino would not be able to retain the program I uploaded, once it is moved to outlet power instead of being power by the PC’s usb cord? Any suggestions would be helpful. Thank you.

Sounds like you are overloading the 5 volt regulator and it’s shutting down from getting too hot, cooling down and coming back on.What is connected to the 5V pin and the output pins? Post a wiring diagram.

Agreed. With 12volt on the DC socket or V-in you can't power a lot from the Mega. Anything more than ~150mA will shut the 5volt regulator down from overheating. Power the Mega with a 5volt cellphone charger connected to the USB socket. Leo..

Hi, Welcome to the forum.

Please read the first post in any forum entitled how to use this forum. http://forum.arduino.cc/index.php/topic,148850.0.html . Then look down to item #7 about how to post your code. It will be formatted in a scrolling window that makes it easier to read.

Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?

Thanks.. Tom.. :)

Crezblaine: it forgets the program I uploaded and then proceeds to perform the factory uploaded L light blinking. Oddly enough the On light blinks along with it. Does anyone have any ideas as to why my Arduino would not be able to retain the program I uploaded, once it is moved to outlet power instead of being power by the PC's usb cord? Any suggestions would be helpful.

If you overwrite the original blink LED program, it is gone, it cannot magically come back unless you uploaded it again.

What you are seeing is some other problem, and the power LED blinking as well suggests a power issue, even the original blink LED program cannot flash the on (power) LED.