I would like to use an arduino motor shield V2 without plugging it into my arduino Mega directly. (The reason is that I would like to be able to use a shield that breaks out the pins into screw connections.)
I'm using external power for the motor shield. I have removed the jumper that controls whether the shield gets power from the arduino.
What pins do I need to connect between the arduino and the motor shield to get it to work? I know I need the ones for I2C:
SDA
SDC
gnd
But that doesn't seem to work. The motor shield library can create the Adafruit_MotorShield and the Adafruit_DCMotor objects, but the motor won't run.
Everything works like it should when the shield is sitting directly plugged into the arduino, but not when I connect with jumper wires.
I'm not much for reading schematics, but it as far as I can see it has pretty much everything connected to everything between the shield and the arduino. But a lot of that is just pass-through and shouldn't be needed. I'm not sure how to tell what needs to be connected.
How are you testing it? Initially, you should only do something simple, like an I2C scan. When you tested the shield plugged in, was it a Mega, or another processor board?
Can you post a list of the pins that you have connected with jumpers? Otherwise we have to guess.
Thanks for all the suggestions! It turns out what I was missing was the 5v pin. The adafruit FAQ said it is required to power the logic on the motor shield. I thought it got its power from the 12v source driving the motors, but apparently not.
