HC-05 4pin Bluetooth Module(Master+Slave) Without Button

This is the Blue variant of the HC-05 4pin Bluetooth Module(Master+Slave) Without Button in Bluetooth and NRF Modules. Available at ₹467.28 (₹396.00 + GST) with free shipping across India.

HC-05 4pin Bluetooth Module(Master+Slave) Without Button

Description:

The HC-05 4-Pin Wireless Serial Bluetooth Module is a versatile Bluetooth solution compatible with any microcontroller. Using the UART protocol, it enables seamless wireless data transmission and reception.

This module can function as both a Master and a Slave device, allowing it to operate as a transmitter or receiver. This dual functionality makes it ideal for connecting to a wide range of devices, including smartphones, computers, keyboards, and other HC-05 modules. To connect with multiple slave devices, however, a master module is required.

Overall, the HC-05 Bluetooth Module offers a flexible and reliable solution for establishing Bluetooth connections in various applications, providing convenience and versatility for wireless communication.

Pin Description:

HC-05 Default Settings:

1. Default Bluetooth Name: “HC-05”
2. Default Password: 1234 or 0000
3. Default Communication: Slave
4. Default Mode: Data Mode
5. Data Mode Baud Rate: 9600, 8, N, 1
6. Command Mode Baud Rate: 38400, 8, N, 1

Applications:

1. Embedded Projects.
2. Industrial Applications.
3. Computer and Portable Devices.
4. GPS receiver.

Features:

1. Working current: matching for 30 mA, matching the communication for 8 mA.
2. Dormancy current: no dormancy.
3. Used for a GPS navigation system, water, and electricity gas meter reading system.
4. With the computer and Bluetooth adapter, PDA, seamless connection equipment.
5. Bluetooth module HC-08 Master and slave Two in one module.
6. Use the CSR mainstream Bluetooth chip, Bluetooth V2.0 protocol standards.
7. Potter default rate of 9600, the user can be set up.
8. Bluetooth protocol: Bluetooth Specification v2.0+EDR
9. Speed: Asynchronous: 2.1Mbps(Max) / 160 kbps, Synchronous: 1Mbps/1Mbps.
10. Security: Authentication and encryption.
11. Profiles: Bluetooth serial port.

Specification:

Tutorial:

Package Includes:

1 X HC-05 4pin Bluetooth Module(Master+Slave) No Button

HC-05 4pin Bluetooth Module(Master+Slave) Without Button Overview

The HC-05 4pin Bluetooth Module (Master+Slave) Without Button is a compact wireless serial interface that supports Bluetooth Specification v2.0+EDR. Designed for seamless UART communication, it can act as either a Master or Slave device, making it ideal for embedded projects and data exchange between microcontrollers, computers, and smartphones.

Key Features of HC-05 4pin Bluetooth Module(Master+Slave) Without Button

• Bluetooth v2.0+EDR compliance with GFSK modulation for reliable data links
• Operates in the 2.4 GHz ISM band with Class 2 emission power (≤4 dBm) and –84 dBm sensitivity
• Dual-mode operation allows configuration as Master or Slave via AT commands
• 4-pin header (VCC, GND, TXD, RXD) without onboard button for streamlined PCB integration
• UART interface supports up to 3 Mbps; default baud rate 9600 bps (8N1)
• Genuine module supplied by Zbotic with fast shipping across India

Applications and Use Cases

• Wireless serial communication between Arduino, ESP32, Raspberry Pi, and other microcontrollers
• Remote control of robots, drones, or RC vehicles via smartphone apps
• Data logging from sensors to PCs or mobile devices without cables
• Bluetooth-enabled home automation switches and smart lighting controls
• Wireless keyboard/mouse interfaces for DIY embedded systems
• Peer-to-peer connection between two HC-05 modules for point-to-point links

How to Use HC-05 4pin Bluetooth Module(Master+Slave) Without Button

Connect VCC to 5 V (or 3.3 V tolerant), GND to ground, TXD to your microcontroller’s RX pin, and RXD to TX. Power up the module and pair it to a host device using the default PIN (“1234” or “0000”). To switch modes, pull the KEY (EN) pin high before power-up and send AT commands over UART at 38400 bps (AT+ROLE=1 for Master, AT+ROLE=0 for Slave).

Why Buy from Zbotic?

• Genuine Products: All items sourced from authorized distributors
• Fast Shipping: Orders ship within 24 hours with tracking (non backordered products)
• Free Shipping: Free delivery on qualifying orders
• COD Available: Cash on Delivery, UPI, cards, net banking
• Technical Support: Expert help for setup and troubleshooting
• Easy Returns: Hassle-free replacement for defective products

Frequently Asked Questions

How do I enter AT command mode without a button?

This module lacks a reset button; to enter AT mode, pull the KEY pin high (to 3.3 V) before powering up. The LED will blink slowly to indicate AT readiness.

What is the default baud rate for normal operation?

By default, the HC-05 communicates at 9600 bps (8 data bits, no parity, 1 stop bit). You can change this via AT commands in AT mode.

Can I pair this HC-05 with a smartphone?

Yes, it appears as a Bluetooth serial port on Android or Windows devices. Use a terminal or custom app to send and receive UART data wirelessly.

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