The **LC-06-R** is a specific variant of the common Bluetooth-to-Serial TTL modules (closely related to the HC-06). It is designed for short-range wireless data communication and is frequently used in Arduino and DIY electronics projects. ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Protocol** | Bluetooth V2.0 + EDR (Enhanced Data Rate) | | **Operating Voltage** | 3.3V to 6V DC (usually integrated with a 3.3V regulator) | | **Logic Level** | 3.3V (Note: 5V systems may require a level shifter) | | **Frequency** | 2.4GHz ISM band | | **Modulation** | GFSK (Gaussian Frequency Shift Keying) | | **Default Baud Rate** | 9600 bps | | **Transmission Range** | ~10 Meters (Class 2) | --- ### 2. Physical Interface (Pinout) Most LC-06-R modules are mounted on a "backplane" (breakout board) with 4 to 6 pins. The standard 4-pin configuration is: 1. **VCC**: Power supply (typically 3.6V - 6V). 2. **GND**: Ground connection. 3. **TXD**: Transmit Data (Serial output to MCU). 4. **RXD**: Receive Data (Serial input from MCU). --- ### 3. Operational Characteristics * **Slave-Only Mode**: Unlike the HC-05 (which can be a Master or Slave), the LC-06/HC-06 series usually operates strictly in **Slave Mode**. This means it can be discovered by a smartphone or PC, but it cannot initiate a connection to another Bluetooth device. * **AT Command Mode**: You can configure the device (change Name, Baud Rate, and Pairing PIN) using AT commands. However, unlike the HC-05, the LC-06 enters AT mode automatically when **not paired** with any device. * **LED Status Indicator**: * **Blinking**: Searching/Waiting for a connection. * **Steady Light**: Connected/Paired with a host. --- ### 4. Typical Wiring Diagram ```cpp // Example Connection to Arduino // LC-06-R Pin -> Arduino Pin // VCC -> 5V // GND -> GND // TXD -> RX (Pin 10 for SoftwareSerial) // RXD -> TX (Pin 11 for SoftwareSerial via Voltage Divider) ``` --- ### 5. Important Usage Notes 1. **Level Shifting**: While the module accepts 5V for power (VCC), the data pins (RXD/TXD) are 3.3V logic. Connecting a 5V Arduino TX pin directly to the LC-06 RXD pin can damage the module over time. It is recommended to use a voltage divider (1kΩ and 2kΩ resistors). 2. **Pairing Code**: The default pairing code is almost always **"1234"** or **"0000"**. ---