DEV Community

Austin Spivey for Wia

Posted on

Driving a DC motor with an Arduino and the L293D motor driver

alt text
In this tutorial, we'll be looking at how to power and drive a DC motor with an L293D and an Arduino (we're using the Arduino MKR 1000 here, but you can use any Arduino that provides enough voltage for your motor, and has 2 digital output pins).
The L293D is a 16-pin Motor Driver IC which can control up to two DC motors simultaneously, in any direction.

You will need

  • Arduino board of your choice
  • Micro USB cable
  • L293D motor driver
  • DC motor
  • Breadboard
  • Jumper wires
  • Arduino IDE

Connecting the components

First, let's hook up the components on the breadboard. Below you'll see a pin diagram of the L293D - note the location of each of the pins, relative to the notch at the top.

alt text

Since we're just driving one motor for this tutorial, we won't be using all of the motor driver's pins.

  • Start by plugging your Arduino into a power source (such as your computer)
  • Connect GND and 5V on the Arduino to one side of the breadboard, and extend to the other side with jumper wires
  • Place the L293D in the center of the breadboard, with half of the pins on either side of the breadboard
  • Connect 5V to Enable 1, Vss, and Vs on the L293D
  • Connect digital output pins (we're using 6 and 7) to input 1 and input 2 on the L293D
  • Connect your Arduino's GND to both GND pins on the same side of the L293D
  • Finally, connect output 1 and output 2 of the L293D to your motor pins

Note: The Vs pin on the motor driver supplies power to the motor. If your motor requires more voltage than your Arduino can provide, you can hook up an external battery or battery pack. Simply connect the negative lead to GND on the breadboard, and the positive lead to the Vs pin of the L293D.

Once that's all connected, it should look a little something like this:
alt text

The Code

Note: If you are completely unfamiliar with the Arduino IDE, watch this video to give you a better understanding of how it works.

In the Arduino IDE:

  • Make sure the correct port is selected under Tools > Port
  • Make sure the correct Arduino board is selected under Tools > Board
  • Click on File > New to create a new Sketch
  • Copy and paste the code below, replacing the motorPin1 and motorPin2 values if you're using output pins other than 6 and 7 on your Arduino
// Define the pin numbers
int motorPin1 = 6;
int motorPin2 = 7;

void setup() {
  // Set the pin modes of the above IO pins to OUTPUT
  pinMode(motorPin1, OUTPUT);
  pinMode(motorPin2, OUTPUT);
}

void loop() {
  // Turn the motor in one direction
  digitalWrite(motorPin1, LOW);
  digitalWrite(motorPin2, HIGH);
}
Enter fullscreen mode Exit fullscreen mode
  • Go to Sketch > Upload to upload the code to your Arduino

Once the sketch is uploaded successfully, the motor will turn in one direction.
If you want to change the direction, simply reverse HIGH and LOW in the loop function.

To take this one step further, connect your device to Wia and add Commands and Flows. If you have any questions, reach out to us using the chat icon at the bottom right hand side of our site!

Top comments (2)

Collapse
 
peter profile image
Peter Kim Frank

Hey Austin, thanks for sharing, this is pretty neat.

Can you provide any fun examples of real-world projects that could utilize this setup and motor? Would love to stoke some inspiration for a future weekend project.

Collapse
 
anspivey profile image
Austin Spivey • Edited

Yes! We used this to create a facial recognition Ferris wheel that would begin turning when you smiled at it and would stop when you frowned, but the possibilities are endless. The full tutorial is to come, and ill be sure to add in some other ideas we have for this!