Bluetooth Communication is a 2.4GHz frequency-based RF Communication which has a range of approximately 10 meters. It is one of the most popular and frequently used low range communication for data transfer. Bluetooth module can be used to control Arduino with a smartphone. Coming to usage of Bluetooth Communication in DIY projects, HC-05 & HC-06 Bluetooth Modules are mostly used in projects. So, in this tutorial, I will discuss both the Bluetooth modules in more detail.
HC-05 Bluetooth Module
The HC-05 module is a Bluetooth Serial port protocol module which means that it communicates with the Arduino through serial communication. This module contains a BC417 Single-Chip Bluetooth IC that is compliant with Bluetooth v2.0 standard and can support both the UART and USB interfaces.
The HC-05 has two operating modes, one is the Data mode in which it can send and receive data from other Bluetooth devices and the other is the AT Command mode where the default device settings can be changed. The HC-05 Bluetooth module has a 3.3 V level for RX/TX and the microcontroller can detect 3.3 V level, so, there is no need to shift the TX voltage level of the HC-05 module. But we need to shift the transmit voltage level from the microcontroller to RX of the HC-05 module.
Specifications
- Low operating voltage: 4V to 6V (Typically +5V)
- Frequency: 2.45 GHz
- Range: <100m
- Follows IEEE 802.15.1 standardized protocol
- Supported baud rates are 9600,19200,38400,57600,115200,230400 and 460800.
- Can operate in Master, Slave or Master/Slave mode
HC-06 Bluetooth Module
The HC-06 Bluetooth module is designed for establishing short-range wireless data communication between two microcontrollers or systems. Once it is paired to a master Bluetooth device such as PC and smartphone, its operation becomes transparent to the user. All data received through the serial input is immediately transmitted over the air.
This module works on Bluetooth 2.0 communication protocol, and it can only act as a slave device. This is the cheapest method for wireless data transmission and more flexible compared to other methods and it even can transmit files at speed up to 2.1Mb/s.
Specifications
- Input voltage: 3.3~6V (Typically +5V)
- Built-in antenna
- Operating Current: 30mA
- Uses Frequency-Hopping Spread Spectrum (FHSS)
- Works with Serial communication (USART) and TTL compatible
- 2.4GHz ISM band frequency
- Default baud rate: 9600
Difference between HC-05 and HC-06 Bluetooth Modules
| HC-05 | HC-06 |
| HC-05 module can either be a master or slave | HC-06 module can only be a slave |
| It has a push button | It does not have a push button |
| HC-05 has five header pins | HC-06 has only four header pins |
Applications
- The Bluetooth module is used for wireless communication between two microcontrollers.
- It is used in Home Automation systems
