The new version of this shield allows for either 3.3 or 5v logic, a separate and more robust VIN connection, and the PWM input has moved to pin 3.This is a motor shield for Arduino that will control two DC motors. Based on the L298 H-bridge, the Ardumoto can drive up to 2 amps per channel. The board takes its power from the same Vin line as the Arduino board, includes blue and yellow LEDs to indicate active direction, and all driver lines are diode protected from back EMF.
Control for motor attached to OUT1/2 is connected to digital line 12 (direction A) and digital line 3 (PWM A).
Control for motor attached to OUT3/4 is connected to digital line 13 (direction B) and digital line 11 (PWM B).
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