嵌入式开发之uart---rs232 和rs485 通用自定义通信协议

http://www.go-gddq.com/html/QiTa-ZongHe_tx/2013-01/992622.htm

http://blog.csdn.net/niuxuheng/article/details/39345241

http://www.cnblogs.com/fyhui/archive/2012/05/03/2480305.html

http://www.cnblogs.com/fyhui/archive/2012/05/01/2478093.html