Arduino with Bluetooth Module HC-05 Connection

When you think about wireless communication a name Bluetooth must come in your mind. there are lots of wireless communication and we use all in transferring data from one point to another point. And here we are working in embedded and robotics. we are controlling things via mobile phone in embedded system and robotics with the help of Bluetooth, and Wi-fi.

Today, we are going to learn Arduino with Bluetooth Module HC-05 Connection.  It is very simple Just you need to connect four wire between Arduino and Bluetooth Module HC-05. HC-05 is most widely used Bluetooth module in the embedded and Robotics. in this article we are going to tell Arduino Uno Bluetooth interfacing. the connection will be the same for Arduino Uno and Arduino Nano. You can easily connect Bluetooth device with the Arduino. just you need to do serial communication between both devices.

To start with both device just look at the features of these devices

1. Bluetooth Module HC-05

Bluetooth module Hc-05 is most widely used Bluetooth module nowadays in the embedded and robotics. It can easily connect with any Bluetooth device. by default, it works as a slave. and we can change its configuration through the AT command. It has two configuration master and slave. we can use it’s both modes. it depends upon the work or projects which we have to make. Arduino Bluetooth interfacing includes UART communication. in which the data store in a parallel change in the serially through the shift register, let us suppose we have an 8-bit data in 8 lines and all data transmitted simultaneously. in that case, we require 8 wires to transmit that data. But in serial communication, we need only one wire to transmit the data. Uart arranges the data in serially with the help of Shift register.

Before the start tutorial Bluetooth Arduino. first, we need to look at some hardware and software features of Bluetooth:-

Hardware Features

• sensitivity nearly ‐80dBm.
• it can work Up to +4dBm RF transmit power.
• input voltage 3.3 to 5 V I/O.
• PIO(Programmable Input/Output) control.
• UART interface with customizable baud rate.
• With an integrated antenna.
• With the edge connector.

Software Features

• Slave default Baud rate: 9600, Data bits:8, Stop bit:1,Parity:No parity.
• having Auto‐connect function. .
• Permit pairing device to connect as default..
• Auto‐pairing PINCODE: ”1234″ and “0000”.

Bluetooth module HC-05 having 6 pins and one Key at the module.

1. Rx:-   It is used to Receive the data (UART serial port receive data).
2. Tx:-   It is used to Transmit the data (UART serial port receive data).
3. RST:- To reset the Module .
4. NC:- It refers to no connections.
5. Vcc:- At Vcc, we give power supply of 5v.
6. GND:- Ground connection.
7. Key:- It use for AT mode.

Circuit Diagram for Arduino with Bluetooth Module HC-05 Connection