串口

串口连线
http://topic.csdn.net/t/20020627/01/832809.html

其实只要买一个串口母头（就是不带针，9个孔的哪种）将串口的2、3脚相连

http://zhidao.baidu.com/question/30630381.html
http://blog.chinaunix.net/u/15586/showart_189530.html
http://blog.csdn.net/paobo/archive/2006/09/27/1294694.aspx
http://community.csdn.net/Expert/topic/5720/5720511.xml?temp=.2956049
http://blog.csdn.net/yefanqiu/archive/2007/04/05/1552651.aspx
http://msmvps.com/blogs/coad/archive/2005/03/23/39466.aspx