差分编码实现通用I/O口串行异步通信的方法

针对微处理器片上串行异步通信接口灵活性欠佳的不足,给出了一种将微处理器通用I/O口扩展成串行异步通信口的方法。利用微处理器自身的定时器,结合有限状态机设计思想,采用差分编码原理在通用I/O口实现了串行异步通信,该方法可以灵活地设定通信帧格式与码元长度。通过示波器检测发送端口的波形,验证了此方法的可行性,在解决通信可靠性和稳定性的同时,为微处理器串行接口的扩展和非标准协议串行通信提供了一种方案,简化了传统串行通信端口的扩展方法。

A Method of Realizing Asynchronous Serial Communication of Universal I/O Port by Differential Coding

As for the inflexibility of the asynchronous communication serial port in microprocessor,provide a method which extends the universal I/O port into asynchronous communication serial port.Combining with the design philosophy of finite state machine,implemented reliable asynchronous serial communication with universal I/O port by using differential encoding and the timers in the microprocessor.And this means can set the format of communication frame and the length of code element conveniently.The waveform gets from oscilloscope indicates that the means come up with is reliable and practical.Thus this means provide a solution fornon-standard serial communication and the extension of the microprocessor serial interface.It also simplifies the traditional method of serial communication port extension.