Dr. P. N. Matte#1, Vishesh Daware#2, Dev Dey#3, Jitesh Chaudhari#4, Pranay Upare#5, Kunal Nande#6 03 06 Based Secure Data and Audio Transmission System using UART Protocol is an innovative approach to achieve secure and highspeed data and audio transmission The system employs visible light signals for communication providing increased security and reduced electromagnetic interference compared to traditional radio frequency RF based methods like WiFi The system architecture integrates a LiFi module with an Arduino microcontroller using the UART protocol enabling asynchronous serial communication for reliable data transfer A highflickering LED array serves as the optical transmitter while a solar panel or LDR acts as the receiver The system demonstrates successful simultaneous transmission of hexadecimal text characters and audio signals displayed on a 162 LCD and reproduced through a speaker respectively The proposed system is suitable for applications requiring high confidentiality such as military communications healthcare and industrial automation Copyright (c) Journal of Science Engineering Technology and Management Science. All rights reserved 2026