Arduino Cookbook, 3rd Edition

Simple Wireless Communication

14.0 Introduction

Arduino’s ability to interact with the world is wonderful, but sometimes you might want to communicate with your Arduino from a distance, without wires, and without the overhead of a full TCP/IP network connection. This chapter covers simple wireless modules for applications where low cost is the primary requirement as well as feature-rich options such as the versatile XBee wireless modules and Bluetooth.

Simple packet radio modules like the RFM69HCW allow secure, reliable communication between devices. XBee provides flexible wireless capability to the Arduino, but that very flexibility can be confusing. This chapter provides examples ranging from simple “wireless serial port replacements” to mesh networks connecting multiple boards to multiple sensors.

Bluetooth Classic and Bluetooth Low Energy are popular options for interfacing with computers and mobile phones. Because those devices typically have Bluetooth these days, it offers a convenient way to make a wireless connection without needing any additional special hardware on your phone or computer.

14.1 Sending Messages Using Low-Cost Wireless Modules

Problem

You want to transmit data between two Arduino boards using inexpensive hardware.

Solution

This recipe uses simple transmit and receive modules based on the RFM69HCW module, which transmits and receives in an unlicensed portion of RF spectrum called the ISM (Industrial, Scientific, and Medical) band. Depending on where ...