bt-arduino-basic.ino

#include <SoftwareSerial.h>

// Pins
#define BT_PIN_TX   7
#define BT_PIN_RX   6
#define BT_PIN_KEY  5

SoftwareSerial BTSerial(BT_PIN_RX, BT_PIN_TX);

void setup()
{
  pinMode(BT_PIN_KEY, OUTPUT);  // this pin will pull the HC-05 pin 34 (key pin) HIGH to switch module to AT mode
  digitalWrite(BT_PIN_KEY, HIGH);
  Serial.begin(9600);
  Serial.println("Enter AT commands:");
  BTSerial.begin(38400);  // HC-05 default speed in AT command more
}

void loop()
{

  // Keep reading from HC-05 and send to Arduino Serial Monitor
  if (BTSerial.available())
    Serial.write(BTSerial.read());

  // Keep reading from Arduino Serial Monitor and send to HC-05
  if (Serial.available())
    BTSerial.write(Serial.read());
}