μC/OS和80C51的固话来电防火墙设计

Landline Calls Firewall Based on μC/OS and 80C51

本设计基于μC/OS-Ⅱ嵌入式实时操作系统和来电显示技术,由铃流检测电路、来电解码电路、DTMF解码电路、模拟挂机电路、号码存储电路等组成。系统利用得到的来电号码,同存储黑名单中的号码进行比较,判断是接通话机振铃线路,还是控制模拟挂机电路挂机。本系统复用电话机键盘控制,并以LCD中文显示,可方便地对黑名单中的号码进行管理。

Based on μC/OS-Ⅱ embedded real-time operating system and CallerID technology, the design is composed of ringing current detection circuit, DTMF decoding circuit, simulation hang up circuit and number storage circuit. The system uses the Caller ID to com-pare with the number of stored blacklist, and judge wether to put through to the phone ringing line, or control simulation hang up circuit to hang up. The system multiplexes telephone keypad control and displays on Chinese LCD, and it is convenient to manage blacklist numbers.