Abstract: Low-cost embedded system based on ARM7 develops a remote surveillance and control system platform and overcomes the problem of data acquisition and processing on a certain communication network.System’s structure and function are given firstly.The microprocessor is AT91SAM7S64 and communicates with PC through USB2.0 interface by the method of asynchronous communication.In hardware design，the chip MT8880 and MT88E39 including their peripheral circuits are constructed for DTMF and FSK signal’s coding and encoding.In software，VC++ is used to implement the firmware program and user program.The experiment shows an efficient result with low-cost and implementation of the stability.

Key words: remote surveillance and control, Advanced RISC Machines（ARM）, USB communication device class

摘要： 基于ARM7开发设计固定电话专网远程监控系统，解决某通信专网的数据无法被远程计算机采集和处理的问题。选用AT91SAM7S64作为微处理器，主机通过USB2.0接口与其通信，采用异步串行方式采集数据；硬件模块构建MT8880和MT88E39专用芯片及相关外围电路，完成双音多频（DTMF）和频移键控FSK信号的编解码；基于C语言完成ARM固件程序和用户程序等软件设计。实验表明系统成本低、运行稳定。

关键词: 远程监控, ARM, USB通讯设备类