MT8880产生发送和接收译码各使用了一片集成电路，而DTMF双向收／发集成电路MT8880专门为双音频信号的收、发而设计，，它既能产生发送双音频信号，又能对双音频信号进行接收译码，还能判断各种信号音(拨号音、回铃音、忙音)。-good 已通过测试。

-MT8880 generate send and receive decoding the use of an integrated circuit, DTMF bi-directional transmit/receive IC MT8880 specifically for the dual audio signal of closing, hair design, it not only generated to send the audio signal, but also two-tone The signal receiving decoder can also determine a variety of tones (dial tone, ring back tone, busy tone).-Good has been tested.