Arduino-megaboard + the motorshield

Hallo.

I am using my mega board * motorshield. When i these boards use with the jumpers on the motorshield VIN then is all OK but when i will use these boards with external power nothing happens. The jumpers on the setmotorshield are set in the PWRIN mode and 12v power to the motorshield. Becomes the megaboard then the power from the motorshield or must i give the megaboard separate power? Best regards, Jack.

Want to draw a quick schematic/take a few photos?

hallo fliggygeek.

I have no schematic from my motorshield. Any other suggestion? Regards, Jack.

Google around and see if you can find the particular board for sale somewhere or the manufacturers site. otherwise take some photos