利用８０３１单片机产生ＤＴＭＦ信号陈彬一ＤＴＭｙ信号简介ＤＴＭＦ（双音多频〕信Ｓ是在程控交换机小广泛采用的一种拨号信号。它设有高频群和低频群两组每组四个，共八个频率。电话号码中每个数字或符号采用八中取二的方法，在高频群和低频群中各取一个频率来表征，加... The use of 8031 ​​single-chip DTMF signal Chen Bin a DTMy signal profile DTMF (dual tone multi-frequency) S is a widely used program-controlled switches in a dial signal.It has two groups of high-frequency and low-frequency group of four each, a total of eight A frequency of each number or symbol in the phone number eight take two methods, in the high-frequency group and low frequency group, respectively, to take a frequency to characterize, add ...