Methods and systems are provided for using an engine laser ignition system to perform a visual inspection of an engine and diagnose various cylinder components and conditions based on engine positional measurements. These buried channel NMOS devices are fabricated with a p-type substrate, an n-type implant in the top portion of the substrate, and an insulating gate dielectric above the n-type implant. A first clock generator is configured to generate a first clock with a first frequency. Each of the first chamber and the second chamber has a capacity of not smaller than 10 pl and not larger than 200 \u03bcl.