找不到设备

[lfqyuan]

Linux 上开发包内的测试程序CommTest ，一直没能搜索到设备。请帮忙解答一下
[root@localhost root]# java CommTest
Experimental: JNI_OnLoad called.
Stable Library
=========================================
Native lib Version = RXTX-2.1-7
Java lib Version = RXTX-2.1-7
金笛短信设备端口连接测试...
找到串口: /dev/ttyS0
Trying at 4800... 没有发现设备!
Trying at 7200... 没有发现设备!
Trying at 9600... 没有发现设备!
Trying at 14400... 没有发现设备!
Trying at 19200... 没有发现设备!
Trying at 38400... 没有发现设备!
Trying at 57600... 没有发现设备!
Trying at 115200... 没有发现设备!
Trying at 128000... 没有发现设备!