Change Default Name and Password of HC-05 Module with AT Commands
Most important part of the device (HC-05) is above Highlighted Button . UNO and HC-05 Connection Module RX - > Uno PIN 11 as TX Module TX - > Uno PIN 10 as RX Module VCC - > Connect UNO 5v PIN OR or UNO PIN 8 (Programmatically it's set to pin mode output and HIGH) Module GND -> UNO GND MODULE Key Or State Pin - > UNO Pin 9 or Uno 3.3v Program : #include <SoftwareSerial.h> SoftwareSerial BTSerial(10, 11); // RX | TX void setup() { pinMode(8, OUTPUT); //for vcc input to module or you can use vcc itself from the UNO pinMode(9, OUTPUT); // this pin will pull the HC-05 pin 34 (key/STATE pin) HIGH to switch module to AT mode digitalWrite(9, 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(BTSeri