Bluetooth Module with Arduino (AT-09, MLT-BT05, HM-10)

In this tutorial, I will dive into the variations of CC2541 BLE board such as the AT-09, MLT-BT05, HM-10, JDY-08, etc. I will use either the specific module name or a blanketed “CC2541-based module” reference to refer to the BLE modules. The general process for interfacing with each module is nearly the same, however, some particularities define how each responds and functions depending on the given firmware. I will also be using the BLExAR app for iOS to communicate with the CC2541 modules.

iPhone Datalogger with Arduino Using The iOS Bluetooth App BLExAR

The BLExAR app will be used in conjunction with a CC2541 (HM-10, JDY-08, AT-09, SH-M08) Bluetooth module and an Arduino (ATmega328) board to create a simple data acquisition system. A DHT22 sensor will provide temperature and humidity data to the Arduino which will be recorded by an iOS device via the BLExAR app. This experiment is a real-world example of an Arduino application demonstrating data acquisition from a real sensor. This tutorial will allow users to solve their own engineering problems using the modern Arduino platform and wireless communication through the BLExAr app, which will ultimately expand the reach and compatibility of technology in the classical sciences through exploration and experimentation.

iOS and Arduino Bluetooth Communication Using The BLExAR App and CC2541 Module

An app called “BLExAR” allows Arduino users to communicate to an iOS device (iPhone or iPad) using a Bluetooth CC2541 module (different versions are called: HM-10, SH-M08, AT-09, or JDY-08). The app permits control of an Arduino board, wireless serial communication, and data acquisition. Click on the app logo shown here to download the app, as it will be used as the iOS communication software. On the Arduino side, we need to wire the CC2541 Bluetooth Low Energy (BLE) module to an Arduino board and upload the appropriate software via the Arduino IDE. In this tutorial, we will demonstrate how to verify communication between an Arduino and CC2541 Bluetooth module, and then use Bluetooth communication to send strings between an iOS device and the Arduino ATmega328p board.