How to Use Bluetooth Mate Gold: Examples, Pinouts, and Specs

The Bluetooth Mate Gold is a wireless communication module designed for easy integration into projects requiring Bluetooth connectivity. It is based on the Roving Networks RN-41 module, which is a small form-factor, low-power Bluetooth radio that supports Bluetooth 2.1 + EDR. The module is perfect for applications such as wireless sensor networks, robot control, or any other projects where a serial cable would be a constraint.

• Wireless data logging
• Remote control for robots or drones
• Serial communication between devices without wiring
• DIY electronics projects with Bluetooth capability
• Home automation systems

• Bluetooth Technology: Bluetooth 2.1 + EDR
• Frequency: 2.4 GHz ISM band
• Modulation: GFSK (Gaussian Frequency Shift Keying)
• Data Rate: Up to 3 Mbps
• Operating Voltage: 3.3V to 6V DC
• IO Voltage: 3.3V (Do not exceed 3.3V on RX or TX)
• Current Consumption: 25mA average, 30mA peak during transmission
• Security: Authentication and encryption
• Range: Up to 100 meters (328 feet) in open space

1. Powering the Module: Connect the VCC pin to a 3.3V to 6V power supply and the GND pin to the ground of your power source.
2. Serial Communication: Connect the TX-O pin of the Bluetooth Mate Gold to the RX pin of your host device (e.g., Arduino UNO), and the RX-I pin to the TX pin of your host device.
3. Pairing: Power the module and pair it with your Bluetooth-enabled device. The default pairing code is usually '1234' or '0000'.
4. Data Transmission: Once paired, you can send and receive data via the Bluetooth connection using standard serial communication protocols.

• Ensure that the power supply is within the specified range (3.3V to 6V DC).
• Do not exceed 3.3V on the RX or TX pins to avoid damaging the module.
• When connecting to a 5V device like an Arduino UNO, use a voltage divider or level shifter for the RX pin.
• Always pair the module with a secure and trusted device to prevent unauthorized access.
• Place the module away from metal objects and other sources of RF interference to maximize range and performance.

#include <SoftwareSerial.h>

// RX, TX pins for the Bluetooth Mate Gold
const int bluetoothTx = 10; // Connect to RX-I of the module
const int bluetoothRx = 11; // Connect to TX-O of the module

SoftwareSerial bluetoothSerial(bluetoothRx, bluetoothTx);

void setup() {
  // Start the serial communication with the host computer
  Serial.begin(9600);
  // Start the serial communication with the Bluetooth module
  bluetoothSerial.begin(115200); // Default baud rate of the module
  Serial.println("Bluetooth Mate Gold is ready to pair");
}

void loop() {
  // Check if data received from the Bluetooth module
  if (bluetoothSerial.available()) {
    char toSend = (char)bluetoothSerial.read();
    Serial.print(toSend); // Send it to the host computer
  }
  // Check if data received from the host computer
  if (Serial.available()) {
    char toSend = (char)Serial.read();
    bluetoothSerial.print(toSend); // Send it to the Bluetooth module
  }
}

• Inability to Pair: Ensure the device is in pairing mode and the correct pairing code is used.
• No Data Transmission: Check the wiring, especially the RX and TX connections. Ensure the baud rate matches the module's default rate.
• Intermittent Connection: Move the module away from metal objects and sources of RF interference.

• Power Issues: Verify that the power supply is stable and within the specified voltage range.
• Correct Baud Rate: Make sure the baud rate in your code matches the module's default baud rate (115200).
• Module Not Discoverable: Reset the module or check if it's already paired with another device.

Q: Can I use the Bluetooth Mate Gold with a 5V microcontroller? A: Yes, but ensure that the RX pin of the module is connected through a voltage divider or level shifter to bring the voltage down to 3.3V.

Q: What is the default pairing code for the Bluetooth Mate Gold? A: The default pairing code is typically '1234' or '0000'.

Q: How can I change the name or baud rate of the Bluetooth Mate Gold? A: You can use AT commands to configure the module. Refer to the RN-41 datasheet for the specific commands and procedures.

Q: What is the range of the Bluetooth Mate Gold? A: The module has a range of up to 100 meters (328 feet) in open space, but this can be reduced by obstacles and interference.