Bluetooth Connection betwenn two Arduinos via Bluetooth

Hey Guys,

I have some question to arduino arduino communication. I hope someone can help me.
My problem is i want to make a master slave communication. For the master i want to use an arduino Feather M0 Bluetooth. The Arduino Feather is calcuating the weight of water. important is that die Master is sending the weight to a seperated arduino via bluetooth. the seperatet arduino will have a lcd on which you can read the weight.

Now my question is what typ of arduino i will need to make a network between the two. and how i can program the master slave relation.

thanks for the help.

greetings vinzenz

Bluetooth should be simple to arrange. It is generally just serial-by-wireless. Any Arduino should be suitable.

It would probably be a good idea to start by communicating between the two Arduinos using wires (Rx, Tx and GND) and when that works you can try replacing the wires with Bluetooth.

If you have an Uno it will make sense to use SoftwareSerial to communicate with the other Arduino and leave HardwareSerial available for uploading programs and debug messages to the Serial Monitor.

Have a look at the examples in Serial Input Basics - simple reliable ways to receive data.


Power for the bluetooth module might be difficult as I understand the Feather is a 3.3v device and there isn't much power around. Most bluetooth modules are on breakout boards running on 3.6 - 6v. This implies that a separate power source is needed. The bare modules are 3.3v but not nice to use but, if you do go that route, a bare HM-10 would definitely be a good idea provided the other bluetooth is also HM-10. The HM-10 is a BLE device - bluetooth low energy - and well-suited for battery operation.

The bluetooths can be configured to auto-connect and the Arduino just write and read serial data

Two gurus