中文摘要：

M—BUS（MeterBus）仪表总线是一种低成本的户用电子系统，可以实现公共事业表的联网和远程抄表功能。公共事业表包括户用电表、水表、热量表等计量仪表。本文讨论仪表总线M—BUS和TTL（Transistor—Transistor Logic）电平之间的接口电路的设计，论述了其通信中的发送和接收机制，并提出了硬件上的设计方案。所设计的接口电路传输距离远、带负载能力强、可靠性高、抗干扰能力强。

英文摘要：

M-Bus bus, a low-cost instrument household electronic system, can achieve public features networking and remote meter reading. Instruments of public utilities include electricity meters, water meters, heat meters and other measuring instruments. The instrument bus, M-BUS （Meter Bus） and the interface between TTL level circuit design and its communication mechanism for sending and receiving are introduced, and hardware design is proposed in this paper. The advantages of the design of the interface circuit include transmission distance, load capac ity, high reliability, and anti-interference ability.