We are going to do a maze solver robot. We bought arduino mega and a clone motor shield.
When arduino connected to pc, motor shield easily drive 2 dc motor without any external power supply.
When i disconnect arduino from pc, and connect it to 9v battery, it resets itself continuously. Then i connected another 9v battery to motor shields external power supply pins. And i get an arduino with 9v and a shield with 9v battery. Motors spin but its again not stable arduino resets itself after 1 seconds.
With a little research i learned i can disable shields ext_power pin which is connecting with arduinos Vinn pin. Tryed this but nothing worked