Lately, I've been working on a wireless remote controller for a Robotic Arm. Most of everything is planned out, but I don't have all the parts and shields yet, so I decided to begin prototyping with a single motor. I am using two Xbee radios for wireless communication. As there are 5 motors and an LED, there aren't enough digital pins for me to communicate in that way, so am using Serial communication from Arduino 1 > Xbee 1 > Xbee 2 > Arduino 2.

So, I decided to make simulations of this but with one wired Arduino. In this Instructable I will be demonstrating how to change a DC motor's direction, using both Serial Commands and commands from buttons. Let's get started, shall we?

Step 1: Setup


In this step, I will provide a parts list and a link to download the Arduino software. I used Arduino Create for this project. You can do the same thing with the Arduino program, which is available for download here.

Parts List:

  • Arduino Uno (other boards may be used)
  • Standard DC motor
  • L293DNE H-Bridge
  • 2 Push Buttons
  • Jumper Wires
  • Breadboard

All of these items can be easily bought online for a very cheap price.

Step 2: Serial Communication - the Wiring

First, let's work on the Serial communication. Wire up the Arduino as demonstrated.

Step 3: Serial Communication - the Code

Now that you have your Arduino wired up, copy and paste this code into the Arduino IDE. What this code does is read for a signal that you would manually type into the Serial monitor. When either 1 or 2 is entered, the motor would turn either clockwise or counterclockwise for a short period of time. Experiment a little! Type in multiple 1's or 2's and see what happens!

int in1pin = 6;
int in2pin = 7; // connections to H-Bridge, clockwise / counter

char receivedChar; // store info boolean newData = false; // create a true/false statement

void setup() {

pinMode(in1pin, OUTPUT); pinMode(in2pin, OUTPUT); // set pins to OUTPUTS

Serial.begin(9600); // start up serial communication }

void loop() {

recvData(); // read and store data

moveMotor(); // move motor according to data and then reset }

void recvData() {

if (Serial.available() > 0) { // if the serial monitor has a reading

receivedChar = Serial.read(); // set char to be what is read newData = true; // make statement true } }

void moveMotor() {

int motordirection = (receivedChar - '0'); // turn recieved data into usable form and give it a name

while(newData == true) {

Serial.println(motordirection); // print motor direction

if (motordirection == 1) { // if it reads 1...

digitalWrite(in1pin, HIGH); // turn motor one way digitalWrite(in2pin, LOW);

delay(250); }

else if (motordirection == 2) { // if it reads 2...

digitalWrite(in1pin, LOW); // turn motor other way digitalWrite(in2pin, HIGH);

delay(250); }

else { // if nothing is read

digitalWrite(in1pin, LOW); // motor is off digitalWrite(in2pin, LOW); }

newData = false; // reset value to false } }

Step 4: Button Commands - the Wiring

For button communication, add buttons as shown.

Step 5: Button Commands - the Code

Now, make a new sketch and copy and paste this code, and play around.

int in1pin = 6;
int in2pin = 7; // h bridge pins

int leftButton = 8; int rightButton = 9; // buttons

void setup() {

pinMode(in1pin, OUTPUT); pinMode(in2pin, OUTPUT); // outputs

pinMode(leftButton, INPUT_PULLUP); pinMode(rightButton, INPUT_PULLUP); // inputs w internal pullup resistors }

void loop() {

int leftPinState = digitalRead(leftButton); int rightPinState = digitalRead(rightButton); // set value names for read data

if (leftPinState == LOW) { // if left button is pressed ...

digitalWrite(in1pin, HIGH); // make motor go one way digitalWrite(in2pin, LOW); }

else if (rightPinState == LOW) { // if right button is pressed ...

digitalWrite(in1pin, LOW); digitalWrite(in2pin, HIGH); // make motor go other way


else { // if neither button is pressed ...

digitalWrite(in1pin, LOW); // nothing happens digitalWrite(in2pin, LOW); } }

Step 6: Useful Links!

Want to learn more about a topic? Check out these links! If you have any questions, comments, or suggestions, feel free to leave them down below!

Serial Communication - http://forum.arduino.cc/index.php?topic=396450

H-Bridges - https://learn.adafruit.com/adafruit-arduino-lesso...

Input Pullup and Constants in general - https://www.arduino.cc/en/Reference/Constants

Using boolean - https://www.arduino.cc/en/Reference/Boolean

- https://www.arduino.cc/en/Reference/BooleanVariab..

About This Instructable



Bio: Building and coding is what I do.
More by KNEXnCoding:How to Install and Use OpenEmu Easiest way to control your Arduino with a Mobile Device! Controlling a DC Motor With Arduino 
Add instructable to: