实现GPS串口读取和GPS路径规划的程序，data.c用于从串口中提取GPS坐标数据，emap.c用于生成实时地图-Achieve the GPS serial port to read and GPS path planning process, data.c used to extract GPS coordinates from the serial port data, emap.c used to generate real-time map

提取GPS接收机报文中的数据，针对log指令“SATXYZ”，提取报文中GPS卫星的id ,GPS时间，3D坐标，钟差-Extract the data in the GPS receiver message, and extract the id, GPS time, 3D coordinates and clock difference of the GPS satellite in the message for the log instruction SATXYZ