A design method of XX2E analog projectile based on STC15W4K56S4 single-chip computer is presented. The structure design is consistent with the shape, weight and loading mode of the real projectile. The circuit control is not only the simulation of electrical characteristics, but also the design of human-computer interaction such as lighting, voice and sound effects. According to the fusing characteristics of bridge wire of electric igniter after XX2E live ammunition excitation, magnetic retaining relay is used as a path control switch, and the working state of contact spring of magnetic retaining relay is monitored in real time. Considering the training requirements, a series of practical functions, such as automatic timing filling and manual filling, fault elimination report number function, excitation current and excitation time reading function are added, which are close to the actual use of the equipment and the detection of the ignition path of the equipment. XX2E is not suitable for the installation of display screen. The actual training is mostly in the outdoor environment and the installation position is not easy to read through the display screen. Therefore, voice broadcasting is used to read all kinds of information. The practical application shows that the design scheme is easy to use, friendly to operate, stable and reliable.