⑴ 铃音检测、计数；⑵ 自动摘挂机；⑶ 密码校验；⑷ 在线修改密码；⑸ 双音频信号解码；⑹ 输入信息分析；⑺ 控制电器开关；⑻ 电器状态查询；⑼ 忙音检测；-⑴ tone detector, count　⑵ Abstract automatically hang up　⑶ cryptographic checksums　⑷ online modify password　of ⑸ dual audio signal decoding　⑹ input information analysis　⑺ control electrical switches　⑻ electrical status query　⑼ busy tone detection