Watchdog

 ✨ š–ššš­šœš”ššØš š¬ š¢š§ š€š®š­šØš¦šØš­š¢šÆšž š„š¦š›šžšššžš š’š²š¬š­šžš¦š¬ ✨

System failures can happen for various reasons, including hardware malfunctions, software bugs, or power issues. When such a failure occurs, having a strategy in place is crucial. If a microcontroller itself fails, how do we ensure a safe state? This is where the watchdog comes into play. By continuously monitoring the microcontroller's operation, the watchdog can detect anomalies and automatically reset the system, helping to restore functionality and maintain safety.

š–š”ššš­ š¢š¬ šš š–ššš­šœš”ššØš ?
A watchdog is a timer that monitors the operation of a system. If the system fails to reset the watchdog within a predetermined time, the watchdog takes action, often resetting the system to prevent malfunction.

š‡šØš° š¢š­ š°šØš«š¤š¬?
1. šˆš§š¢š­š¢ššš„š¢š³ššš­š¢šØš§: When the system starts, the watchdog timer is initialized to a specific timeout value based on the expected operational cycles.
2. š‘šžš š®š„ššš« š‘šžš¬šžš­š­š¢š§š : During normal operation, the embedded system continuously resets (or “kicks”) the watchdog timer at regular intervals. This signals that the system is functioning correctly.
3. šŒšØš§š¢š­šØš«š¢š§š : The watchdog continuously monitors the system’s activity. If it detects that the timer has not been reset within the set time-frame, it interprets this as a potential fault.
4. š…ššš¢š„š®š«šž š‘šžš¬š©šØš§š¬šž: Upon detecting a failure, watchdog can automatically reset the system, bringing it back to a known good state. In some implementations, it can log the error for diagnostics, allowing engineers to analyze the fault after recovery.
5. š…ššš¢š„-š’šššŸšž šŒšžšœš”ššš§š¢š¬š¦: This process acts as a fail-safe, ensuring that critical automotive functions like braking, steering, and engine control remain operational even in the event of a software glitch or hardware malfunction.

In the automotive industry, where embedded systems control everything from engine management to safety features, a watchdog is indispensable. It not only enhances system reliability but also builds consumer trust in our vehicles.

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Author : DHEERJ PšŸ˜Š

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