HC-05 Bluetooth Module – SPP, 2.4GHz, Master/Slave
HC-05 Bluetooth Module – SPP Protocol, Master/Slave, 2.4GHz
The HC-05 is a versatile Bluetooth serial communication module that enables wireless data transfer between microcontrollers and other Bluetooth devices. It operates on the SPP (Serial Port Profile) protocol and can be configured as a master or slave, making it ideal for projects that require cable-free serial links. With a range of up to 10 meters and support for common baud rates, it’s a staple in IoT, robotics, and home automation.
Key Specifications
| Specification | Value |
|---|---|
| Bluetooth Version | V2.0+EDR |
| Frequency | 2.4GHz ISM band |
| Operating Voltage | 3.3V (5V tolerant on RX) |
| Current | 30mA (paired), 8mA (standby) |
| Range | Up to 10 meters (open space) |
| Baud Rate | 9600bps default (adjustable up to 1382400) |
What You Can Build With This
- Wireless serial monitor for Arduino projects
- Bluetooth-controlled robot or RC car
- Home automation system with smartphone app
- Wireless sensor data logger
Compatibility
The HC-05 works with any microcontroller that has a UART/serial interface, including Arduino Uno, Mega, Nano, ESP32, and Raspberry Pi (with level shifting). It uses 3.3V logic, but the RX pin is 5V tolerant, allowing direct connection to 5V MCUs. Common pairings include using it with an Arduino Uno for a Bluetooth-controlled LED matrix or a Raspberry Pi for a wireless serial gateway.
Wiring Notes
Connect VCC to 3.3V (or a regulated 5V if the module has an onboard regulator), GND to common ground, TX of HC-05 to RX of MCU, and RX to TX. Do not exceed 5V on the RX pin. For AT command mode to change settings, enter command mode by pulling the KEY/EN pin high before powering up or pressing a button on some modules.
Why Buy from Compoden
Every component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-5 days. If defective on arrival, replace within 7 days.
Is this compatible with Arduino Uno?
Yes, the HC-05 works perfectly with Arduino Uno. Connect HC-05 TX to Arduino RX (pin 0) and RX to TX (pin 1). Use the SoftwareSerial library if you need to keep the hardware serial for programming.
How do I switch between master and slave mode?
Mode can be switched using AT commands via the serial interface. Enter command mode by pulling the KEY pin high before powering, then send AT commands to set the role.
Can I power it directly from a 5V Arduino pin?
Most HC-05 modules have a voltage regulator and can be powered from 5V, but check your module’s labeling. If not, use a logic level converter or power from 3.3V.
📦 Free Setup Handoff Document Included
Every Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.
What you can build with this
Shipping Information
- Prepaid Orders: ₹75 for orders up to ₹999, FREE shipping above ₹999
- COD Orders: ₹125 shipping + ₹50 COD fee = ₹175 total
- Delivery Timeline: Dispatch in 1-2 days, delivery in 2-7 days depending on location
Returns & Warranty
- 7-Day Return: Manufacturing defects only (approval required)
- Warranty: 7 days from delivery
- Non-Returnable: Batteries, consumables, cut wires, clearance items