基于89c51的USBN9603头文件，用于USBN9603开发板。-The USBN9603 header file based on 89c51 ，is used for development board by USBN9603.

四驱DYI竞赛小车驱动源代码，用89c51单片机控制的 用tcrt5000红外反射式光电传感器寻迹-Four-wheel drive the DYI competition car driver source code control with 89c51 microcontroller with tcrt5000 infrared reflective photoelectric sensor tracking