Hello, I bought this motor driver shield to use with Arduino Mega 2560. I have the shield connected to both Motor 1 and Motor 2. I used an external power supply to provide power to the motors. The Arduino is powered by either a battery box of 2xAA batteries or via the usb port of my computer.
When I commanded both motors to turn forward at the same time using:
Motor 2 turned reasonably fast but Motor 1 either did not turn or turned so slooooooowly that it looked like it did not turn. I also heard strange noise like “dooooooo doooooo dooooooo” continuously. However, when I disconnected Motor 2 from the shield, Motor 1 immediately turned reasonably fast.
When I changed the program so that only one motor turned at a time, there is no such problem.
Know how to correct this problem?