介绍微机保护通讯系统的结构、特点及要求，提出微机保护通讯网络宜采用星型拓扑结构，网络管理由中心主节点通讯管理机来实现；讨论单片机普通串行通讯方式对微机保护现场单元实时性的影响；结合开发微机保护通讯管理机，介绍在通讯系统中如何利用80C196KC单片机的PTS功能，实现现场通讯的微代码化。针对PTS一次传送模式被传数据定长的特点，提出应在通讯协议中指定下行数据包的长度及格式，并采用数据包冗余技术，提高通讯可靠性。

This paper presents structure, characteristic and condition of microprocessor based relay communication system. A available start network configuration for the system is put forward. Message manager is used in the net. Some problems appearing in serial communication of field unit are also discussed. A way is brought forward for the communication system, which is an application of PTS function of 80C196KC SCM. The order is proposed for the PTS's one transmission model, which is the data longness must be destined in the net message agreement. A data redundance technic is adopted for improved message dependability.

TN913