HM-10 Bluetooth Module

This module is equipped with Bluetooth functionality.

It can also be used as a beacon.

Specifications

• Operating Voltage: 5V
• Bluetooth Version: 4.0
• Default Name: HMSoft
• Default Baud Rate (Serial Connection): 9600

Required Hardware

• HM-10
• Arduino UNO
• UNO Cable
• F-M Cable (4 pieces)

Connection

TXD and RXD can be connected to any digital pin on the UNO board as desired (in this text, D6 and D7 are used).

HM-10	Arduino Uno
GND	GND
VCC	5V
TXD	D6
RXD	D7

Library

SoftwareSerial (default library)

AT Command

• The Bluetooth status can be checked using AT commands.
• AT commands can be sent via the Serial Monitor.
• The datasheet describes the AT commands available (different from those of the HC-06 Bluetooth module). Refer to the HM-10 Datasheet.

Example Code

// Include the library for serial communication
#include <SoftwareSerial.h>

// Create a SoftwareSerial object for Bluetooth communication
SoftwareSerial BTSerial(6, 7);

void setup()
{
  // Set baud rate
  Serial.begin(9600);
  BTSerial.begin(9600);
  Serial.println("Serial communication started");
}

void loop()
{
  // If data is received from the Bluetooth serial, print it to the Serial Monitor
  while (BTSerial.available() > 0)
  {
    byte data = BTSerial.read();
    Serial.write(data);
  }

  // If data is received from the Serial Monitor, send it over Bluetooth serial
  while (Serial.available() > 0)
  {
    byte data = Serial.read();
    BTSerial.write(data);
  }
}

Operation Check

After uploading the code, enter AT in the Serial Monitor to test the operation.

If OK is displayed, the module is functioning correctly.

Bluetooth Terminal Application Test

1. Install a Bluetooth terminal application on your smartphone. The type of application does not matter.
2. Connect to the HM-10 Bluetooth module within the application.
3. Messages entered in the app will be displayed on the Serial Monitor, and vice versa, messages entered in the Serial Monitor will be displayed in the app.