Connecting Arduino Uno to a smartwatch via bluetooth I have a U80 Smartwatch from Bluetooth Watch International, which has bluetooth function. It is meant to be connected via to my smartphone (and it works perfectly).

I also have an Arduino Uno board and a corresponding BLE ZS-040 bluetooth chip. 

I need for my smartphone to be able to detect my Arduino board, so I can send data from a simple circuit connected to the Arduino board to the smartphone.

Basically, my circuit is meant to be a simple push button. When the button is pushed, and the circuit is closed, the Arduino board will send a signal to the smartwatch. This will cause the smartwatch to ring and vibrate, as if it is receiving a call. Then to turn off the ringing and vibrating, the user can simply 'answer the phone call', and it will stop.

From what I understand, (I'm very new to Arduino) I have to connect the Arduino board to the smartwatch first, which means I have to somehow get the board to be detected by my watch, which it's not doing yet, eventhough the bluetooth module is connected to the board.

Then the push button needs to send a signal to the watch. Which means the command {if buttonpush='1', send (receiving call)}, so when the button is pushed, the signal is sent and the watch acts as if it is receiving a call. Basically showing all the physical signs (eg. vibrating and/or ringing based on the watch's setting, showing 'answer/deny call', etc.). Btw, the push button is not to be held down. As long is the button is pushed and released once, the signal should be sent, and the watch will buzz until the 'phone call' is answered or denied.


I have absolutely no idea how to get the board connected to the smartwatch via bluetooth.
And while I have a rough idea on the push button circuit I need, I also need to send the signal for the watch to act like it has received a call.


Mainly, I'm looking for any help with coding here. If anyone can help with the physical circuit connections, that would be awesome too.
HC-05 is a Bluetooth 2.1 SPP only chip (BR/EDR). Your bluetooth watch will be Bluetooth Low Energy 4.x (BLE Single Mode).

The two are not compatible.

You will need a BLE module for the Arduino which is capable of running as a "Central Device".