摘要
介绍了单片机与双音多频(DTMF)信号收发芯片MT8880的直接接口设计方法。其特点是利用单片机的I/O口模拟产生MT8880的接口信号时序,得到无其它外围芯片的直接接口。文章以单片机89C2051为实例,给出了MT8880与其连接时的硬件和软件设计。本方法已在电话终端产品中获得应用。
This paper describes the design method of direct interface between
MPU and DTMF signal transceiver chip MT8880, which features with generation and simulation of
MT8880 interface signal time order by using MPU’s I/O ports and gets the direct interface without
any peripheral circuits.Hardware and software designs for MT8880 interfacing with 89C2051 are
presented.This method has been used in telephone terminal products.