Note: HC-05 bluetooth module will only work with Arduino UNO R3. It will not work in other arduino boards like nano,R4,etc.
Points to Remeber before connection:
- You must first pair the "HC-05" bluetooth module. Open your bluetooth and scan for available devices. You will find a device named "HC-05". Click on it and pair. DO NOT CONNECT, JUST PAIR.
- Make sure no other devices is connected with bluetooth like earbuds, smart watch, speaker, etc., as it may cause problem in connection with bluetooth module.
Watch How to Connect HC-05 Bluetooth Module with App