DC motors are used for all sort of robotic projects.
The motor FeatherWing can drive up to 4 DC motors bi-directionally. That means they can be driven forwards and backwards. The speed can also be varied at 0.5% increments using the high-quality built in PWM. This means the speed is very smooth and won't vary!
Note that the H-bridge chip is not meant for driving continuous loads of 1.2A, so this is for small motors. Check the datasheet for information about the motor to verify its OK!
Connecting DC Motors
To connect a motor, simply solder two wires to the terminals and then connect them to either the M1, M2, M3, or M4. Then follow these steps in your sketch
#include <Wire.h> #include <Adafruit_MotorShield.h> #include "utility/Adafruit_PWMServoDriver.h"
Adafruit_MotorShield AFMS = Adafruit_MotorShield();
Adafruit_DCMotor *myMotor = AFMS.getMotor(1);
with getMotor(port#). Port# is which port it is connected to. If you're using M1 its 1, M2 use 2, M3 use 3 and M4 use 4
Connect to the Controller
In your setup() function, call begin() on the Adafruit_MotorShield object:
AFMS.begin();
Set default speed
Set the speed of the motor using setSpeed(speed) where the speed ranges from 0 (stopped) to 255 (full speed). You can set the speed whenever you want. Note that the PWM range is 12-bit but to maintain backwards-compatibility with analogWrite we use 8 bits only. If you really need 12-bits, you'll need to drive the PCA9685 'by hand' which is not covered here!
myMotor->setSpeed(100);
Run the motor
To run the motor, call run(direction) where direction is FORWARD, BACKWARD or RELEASE. Of course, the Arduino doesn't actually know if the motor is 'forward' or 'backward', so if you want to change which way it thinks is forward, simply swap the two wires from the motor to the shield.
myMotor->run(FORWARD);
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