This paper also an example of the DTMF experiment,programmes according to the related function , translates and edits and links to the main program to verify the result.

• 以双音多频(DTMF)实验为例 ,根据相关函数编写了功能程序模块 ,并与主程序连接 ,进行编译和运行 ,使实验结果得以验证