The Extended Range Guided Munition (ERGM) Smart Trainer, developed at Naval Sea Systems Command Indian Head Division (NAVSEA Indian Head), is intended for use as both a training round and diagnostic tool on the Navy's new MK 45 Mod 4 naval gun and related gunnery equipment. Designed with cost-effective military use in mind, the Smart Trainer provides several example techniques using rugged commercial electronics in embedded system applications with specialized interfaces. It also offers an unorthodox signal processing method using the familiar 555 timer and programmable logic in a DPLL.