从文件读取7路数字信号(存储为char型)， 输出2路信号是输入信号的当前值与前2次 的逻辑组合。用屏幕和文件分别输出信号，用字符代表光点模拟输出结果波形。输出 结果由已有函数intf1(char d2,char d1,char d)，intf2(char d2,char d1,char d) 给出 函数的输入参数d2,d1,d分别用低7位表示7路前2次信号及当前信号-7 digital signals read from the file (stored as char type)

该程序基于STM32F4，实现读取波形的功能(The program is based on STM32F4 to realize the function of reading the waveform)