使用STC89C51单片机通过串口通信与扫码枪通信，使用扫码枪扫描二维码，实现二维码解锁，掉电保护等功能，(Using STC89C51 MCU to communicate with scavenger gun by serial communication, scanning two dimensional code using a scavenging gun to realize two dimensional code unlocking and power drop protecti