Thanks for the replies guys.
If I just have the usb plugged in all works fine and the lcd works perfect. When I power up my 12v the lcd greys out. I can still see the menu but it's washed out. I can still run all the functions and that's what perplexes me. I'm leaning twards the mega. I think your both right. I blew the mega voltage reg and it's not supplying the proper voltage or current to the lcd. So when I just use the usb 5v lcd is fine.
How does the mega switch between usb supply and external ?
I have another mega I'm going to try. Are there any tests I can do before I plug in the other mega?
Thanks again as you can tell my electronics is less than stellar.
If I just have the usb plugged in all works fine and the lcd works perfect. When I power up my 12v the lcd greys out. I can still see the menu but it's washed out. I can still run all the functions and that's what perplexes me. I'm leaning twards the mega. I think your both right. I blew the mega voltage reg and it's not supplying the proper voltage or current to the lcd. So when I just use the usb 5v lcd is fine.
How does the mega switch between usb supply and external ?
I have another mega I'm going to try. Are there any tests I can do before I plug in the other mega?
Thanks again as you can tell my electronics is less than stellar.