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@article{198916,
        author = {KANNAN S and MADHAN P and GANESH KUMAVATH and KAMALESH KUMAR S},
        title = {LoRa SMART NOTICE BOARD WITH ARM-BASED HMI},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {12},
        number = {11},
        pages = {10678-10683},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=198916},
        abstract = {Real-time information dissemination across large campuses is a critical requirement in modern educational and industrial environments. This paper presents the design and implementation of an infrastructure-independent wireless smart notice board utilizing Sub-GHz LoRa telemetry and advanced Human-Machine Interface (HMI) technology. A primary challenge in remote wireless displays is the processing bottleneck caused when a host microcontroller handles both network reception and pixel-by-pixel graphical rendering. To resolve this, the proposed architecture integrates a Nextion NX3224K028 display featuring a dedicated 48 MHz ARM Cortex processor. By completely offloading the GUI rendering to this edge-processing HMI, the receiver ESP32 maintains optimal network polling speeds. Text data is captured via a Bluetooth smartphone application, processed by a gateway ESP32, and broadcasted over the 433 MHz ISM band using HC-12 LoRa transceivers. Experimental results demonstrate a reliable packet delivery rate exceeding 95%, a non-line-of-sight communication range of up to 1000 meters, and an end-to-end update latency of less than one second.},
        keywords = {ARM processor, LoRa, HC-12, ESP32, Nextion HMI, Wireless Notice Board, Edge Rendering, Sub-GHz communication.},
        month = {April},
        }