详情请点击：<BR> <img align=absmiddle src=http://www.gkong.com/learn/pic/url.gif border=0><a target=_blank href=http://www.icop.com.cn/tech/dmp-hw/serial/485test_serial.pdf>http://www.icop.com.cn/tech/dmp-hw/serial/485test_serial.pdf</a>