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@article{195285,
        author = {Dr. Jamuna M and Nagasmruthi R A and Sanjana Balaramsingh Hajeri and Sanjana K and Sanya S},
        title = {Design and FPGA Implementation of a Watchdog Timer for Safety-Critical Embedded systems},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {12},
        number = {10},
        pages = {7441-7449},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=195285},
        abstract = {Reliable supervision mechanisms are essential in safety-critical embedded systems where uninterrupted operation is mandatory. This paper presents the design and implementation of a hardware-based windowed watchdog timer using FPGA for monitoring microcontroller-driven sensor applications. The proposed system integrates an FPGA-based watchdog, an Arduino Nano for environmental sensing using a DHT11 sensor, and a MATLAB-based supervisory interface for real-time visualization and recovery.
Unlike conventional watchdog timers that rely solely on timeout counters, the proposed architecture incorporates configurable frame and service windows, pattern-based verification, and UART-based supervision. The FPGA validates servicing signals and detects early, late, or incorrect refresh attempts. Upon detecting abnormal behaviour, a reset pulse is generated and transmitted to MATLAB, which initiates automatic recovery of the Arduino application.
The system was evaluated under various operating scenarios including normal execution, delayed servicing, incorrect pattern transmission, UART communication delay, and forced microcontroller freeze. Experimental and simulation results confirm accurate fault detection and reliable closed-loop recovery. The integration of deterministic hardware timing and software-based corrective action enhances robustness and makes the architecture suitable for industrial monitoring, environmental sensing, and long-duration embedded systems.},
        keywords = {FPGA, Watchdog Timer, Windowed Watchdog, Safety-Critical Systems, UART Communication, Embedded Systems, Fault Detection, MATLAB Supervision},
        month = {March},
        }