Hi, I am currently doing a project regarding gear detector. Basically, I am trying to detect a error when a specified gear is being used. I am thinking of reflecting the error detected using a LED and speaker by giving a continuous short beeping sound and intermittent light up of the LED until the error is being rectified. I have a rough sketch in my mind how the circuit will work but technically, I am not good enough as I am in my first grade of engineering studies. Anyone is helpful enough to give some suggestion on how I should go about designing the circuit? Do I need to use a timer or just gates alone are enough? I am not a expert so please correct me should I have used a wrong description. Thanks in advance.