Browse over 10,000 Electronics Projects

Classic Bluetooth® Communication Using Microchip RN41/42 Module and 8-bit PIC® Microcontroller

Classic Bluetooth® Communication Using Microchip RN41/42 Module and 8-bit PIC® Microcontroller

Most of the embedded applications require real-time communications to support their ecosystem. Standard wired communication, such as RS232, RN422, RS485 or Ethernet are not easily used due to the infrastructure support required by the end application. Wi-Fi® and Bluetooth® have emerged as the standards of choice for connecting embedded applications to the cloud through a router, smartphone or tablet.

Bluetooth is known to provide easy, temporary connectivity to smartphones/tablets, and is supported by Android™ and iOS® applications. It provides a convenient cable replacement communication medium for applications involving audio streaming and data synchronization between devices. Bluetooth data transfer rate has increased to 3 Mbps with the Enhanced Data Rate version (Bluetooth 2.1 + EDR), and further advanced to a high-speed version (Bluetooth 3.0 + HS) to support large file transfers.

Bluetooth Low Energy (BLE) technology is introduced through Bluetooth version 4.0 from Special Interest Group (SIG) and with this, there has been a considerable interest in various application possibilities in different market segments. BLE works with extremely low-power, unique features and also supports new services/profiles.


Bluetooth Classic and LE technology are quite different from one another, thus, user has to consider the technology which meets the applications requirements. However, both Classic Bluetooth and BLE have found presence with the Internet of Things (IoT) that requires ease of network connectivity by enabling physical objects or devices to connect and exchange data.

The primary purpose of this application note is to help users or application developers to have a quick understanding of the interface requirements and the process of communication between the Classic Bluetooth Microchip RN41/42 module and the PIC18 (8-bit) microcontroller over the UART using the ASCII command interface. It essentially supports the application developers with an interface framework in using the Microchip Bluetooth Module and the MCU which are suitable for IoT and related applications.