Wireless communication is cheap and easy with arduino and the NRF24L01 module.
We are going to build a simple alarm that can be controlled from a remote arduino with the push of a button.
Step 1: Wireless Module and Wiring
The wireless module we are using is the NRF24L01. It is a cheap radio operating at 2.4 Ghz.
Follow the schematics and wire up the two arduinos like in the picture
Step 2: Code
Code for master and slave can be found herehttps://create.arduino.cc/editor/gaptrast/5f762005...