本文介绍了4 串口扩展芯片26C94 的特性和外部接口电路,讨论了由嵌入式计算机PC104 和26C94 等构成的某飞控机串口通信系统,给出了系统的硬件接口电路和部分软件编程。 Abstract: In this paper, the characteristic and interface of quad universal asynchronous receiver/transmitter (QUART) is introduced. The serial communication system composed embedded computer PC104 and 26C94 is discussed. The hardware configure and software design are described. Key words: serial communication; 26C94 chip; embedded computer PC104.