Using the Arduino Uno and HC-05 Bluetooth Module

I always ask myself, can I create something with the HC_05 Bluetooth module? So I did a little research and guess what--it wasn't that hard do it. So I have also taken it upon myself to show you guys how you can also have fun with this interesting module.

This tutorial is to help you with the basic connections of the HC-05 Bluetooth module. The tutorial is in two parts. The first Section is to help you setup the basic parameters of your Bluetooth module, such as the password and MAC-Address.

The second section is to help you use the Ardudroid App to connect to the Bluetooth module, as well as use it to control LEDs and a buzzer.

Enjoy!!!!!!!

Components Needed for This Project

Hardware Components

• Arduino Uno : https://www.sparkfun.com/products/11021

• Ultrasonic Sensor (4 pinout) : http://letsmakerobots.com/node/30209

• Jumper wires : https://www.sparkfun.com/products/11026

• RGB led: http://www.aliexpress.com/item/3-Color-RGB-LED-Mod...

• Breadboard : https://www.sparkfun.com/products/12615

• HC-05 Bluetooth module : http://www.emartee.com/product/41656/

• Piezoelectric Buzzer; https://www.adafruit.com/product/160

• Resistors. (Kindly note that the Resistor are connected in series and also their values are 2Kohm and a 1kohm)

Software

• ArduDroid App by TechBitar : https://play.google.com/store/apps/details?id=com....

Breadboard View and Circuit Diagram

Attached are the Breadboard view and the Circuit diagram of the Project.

Arduino Code

Kindly note that, this is the original code of the ArduDroid App for the Arduino version, but I did a little edit to suite this tutorial. Also you will note that with most of the code I have commented out, it is because I do not need it. You can also go ahead and make any changes you need. I hope this helps.

 /* 
PROJECT: ArduDroid  
PROGRAMMER: Hazim Bitar (techbitar at gmail dot com) 
DATE: Oct 31, 2013 
FILE: ardudroid.ino 
LICENSE: Public domain 
*/ 
#define START_CMD_CHAR '*' 
#define END_CMD_CHAR '#' 
#define DIV_CMD_CHAR '|' 
#define CMD_DIGITALWRITE 10 
#define CMD_ANALOGWRITE 11 
#define CMD_TEXT 12 
#define CMD_READ_ARDUDROID 13 
#define MAX_COMMAND 20  // max command number code. used for error checking. 
#define MIN_COMMAND 10  // minimum command number code. used for error checking.  
#define IN_STRING_LENGHT 40 
#define MAX_ANALOGWRITE 255 
#define PIN_HIGH 3 
#define PIN_LOW 2 
#include <NewPing.h> 
#define TRIGGER_PIN  12  // Arduino pin tied to trigger pin on the ultrasonic sensor. 
#define ECHO_PIN     11  // Arduino pin tied to echo pin on the ultrasonic sensor. 
#define MAX_DISTANCE 200 // Maximum distance we want to ping for (in centimeters). Maximum sensor distance is rated at 400-500cm. 
NewPing sonar(TRIGGER_PIN, ECHO_PIN, MAX_DISTANCE); // NewPing setup of pins and maximum distance. 
#define BUZZER_PIN 9 
#define red_LED  4 
#define green_LED  5 
#define blue_LED  6 
String inText; 
void setup() { 
 Serial.begin(9600); 
 Serial.println("ArduDroid 0.12 Alpha by TechBitar (2013)"); 
 //Serial.flush(); 
} 
void loop() 
{ 
 Serial.flush(); 
 int ard_command = 0; 
 int pin_num = 0; 
 int pin_value = 0; 
 char get_char = ' ';  //read serial 
 // wait for incoming data 
 if (Serial.available() < 1) return; // if serial empty, return to loop(). 
 // parse incoming command start flag  
 get_char = Serial.read(); 
 if (get_char != START_CMD_CHAR) return; // if no command start flag, return to loop(). 
 // parse incoming command type 
 ard_command = Serial.parseInt(); // read the command 
 // parse incoming pin# and value   
 pin_num = Serial.parseInt(); // read the pin 
 pin_value = Serial.parseInt();  // read the value 
 // 1) GET TEXT COMMAND FROM ARDUDROID 
 if (ard_command == CMD_TEXT){    
   inText =""; //clears variable for new input    
   while (Serial.available())  { 
     char c = Serial.read();  //gets one byte from serial buffer 
     delay(5); 
     if (c == END_CMD_CHAR) { // if we the complete string has been read 
       // add your code here 
       break; 
     }               
     else { 
       if (c !=  DIV_CMD_CHAR) { 
         inText += c;  
         delay(5); 
       } 
     } 
   } 
 } 
 // 2) GET digitalWrite DATA FROM ARDUDROID 
 if (ard_command == CMD_DIGITALWRITE){   
   if (pin_value == PIN_LOW) pin_value = LOW; 
   else if (pin_value == PIN_HIGH) pin_value = HIGH; 
   else return; // error in pin value. return.  
   set_digitalwrite( pin_num,  pin_value);  // Uncomment this function if you wish to use  
   return;  // return from start of loop() 
 } 
 // 3) GET analogWrite DATA FROM ARDUDROID 
 if (ard_command == CMD_ANALOGWRITE) {   
   analogWrite(  pin_num, pin_value );  
   // add your code here 
   return;  // Done. return to loop(); 
 } 
 // 4) SEND DATA TO ARDUDROID 
 if (ard_command == CMD_READ_ARDUDROID) {  
   // char send_to_android[] = "Place your text here." ; 
   // Serial.println(send_to_android);   // Example: Sending text 
   //Serial.print(" Analog 0 = ");  
   //Serial.println(analogRead(A0));  // Example: Read and send Analog pin value to Arduino 
   delay(500);                      // Wait 50ms between pings (about 20 pings/sec). 29ms should be the shortest delay between pings. 
 unsigned int uS = sonar.ping(); // Send ping, get ping time in microseconds (uS). 
 Serial.print("Ping:"); 
 Serial.print(uS / US_ROUNDTRIP_CM); // Convert ping time to distance in cm and print result (0 = outside set distance range) 
 Serial.println("cm"); 
    if (uS / US_ROUNDTRIP_CM <= 10) 
   { 
 Serial.print("OBSTRUCTION"); 
   return;  // Done. return to loop(); 
   } 
        if (uS / US_ROUNDTRIP_CM > 10) 
   { 
 Serial.print("NO OBSTRUCTION"); 
   return;  // Done. return to loop(); 
   } 
 } 
} 
// 2a) select the requested pin# for DigitalWrite action 
void set_digitalwrite(int pin_num, int pin_value) 
{ 
 switch (pin_num) { 
 /*case 13: 
   pinMode(13, OUTPUT); 
   digitalWrite(13, pin_value);   
   // add your code here       
   break; 
 case 12: 
   pinMode(12, OUTPUT); 
   digitalWrite(12, pin_value);    
   // add your code here        
   break; 
 case 11: 
   pinMode(11, OUTPUT); 
   digitalWrite(11, pin_value);          
   // add your code here  
   break; 
 case 10: 
   pinMode(10, OUTPUT); 
   digitalWrite(10, pin_value);          
   // add your code here  
   break;*/ 
 case 9: 
   pinMode(9, OUTPUT); 
   digitalWrite(9, pin_value);          
   // add your code here  
   break; 
 /*case 8: 
   pinMode(8, OUTPUT); 
   digitalWrite(8, pin_value);          
   // add your code here  
   break; 
 case 7: 
   pinMode(7, OUTPUT); 
   digitalWrite(7, pin_value);          
   // add your code here  
   break;*/ 
 case 6: 
   pinMode(6, OUTPUT); 
   digitalWrite(6, pin_value);          
   // add your code here  
   break; 
 case 5: 
   pinMode(5, OUTPUT); 
   digitalWrite(5, pin_value);  
   // add your code here        
   break; 
 case 4: 
   pinMode(4, OUTPUT); 
   digitalWrite(4, pin_value);          
   // add your code here  
   break;/* 
 case 3: 
   pinMode(3, OUTPUT); 
   digitalWrite(3, pin_value);          
   // add your code here  
   break; 
 case 2: 
   pinMode(2, OUTPUT); 
   digitalWrite(2, pin_value);  
   // add your code here        
   break;*/       
   // default:  
   // if nothing else matches, do the default 
   // default is optional 
 }  
} 

Video of the Project

Enjoy the video, it is more in-depth.

Pictures of the Project