硬件扩展单片机多串口通讯方式的研究

Study on Single-Chip Microcomputer Multi-port Serial Communication Based on Hardware Extension

单片机一般只可以提供1个到2个串口,而现实中的工程和科学研究需要单片机控制多个串口的外设。提出利用增加硬件的方式把一个串口扩展成为多个串口,第一种方法是根据信号切换的原理的CD4052模拟数据选择/分配器,第二种是利用6个IO口选择子串口同时复用一个中断来扩展串口的芯片SP2539,并且把这两种方式应用到实际的电路设计中,硬件结构简单,可靠性高,达到很好的效果。这两种方式为串口的扩展提供了一种新方法。

There is one or two serial communication port in the single-chip microcomputer.However,multi-port serial communication is demanded in the reality of the engineering and scientific research.CD4052 analog multiplexers/de-multiplexers based on the principles of signal switching,SP2539 based on using six IO ports to select one of sub-serial port and reuse of an interrupt are used to extend single-chip microcomputer serial port.These two methods could achieve good effects in real circuit design.