当运行
#minicom
device /dev/modem access failed :no such file or directory
修改方法1：
在root权限下：用minicom -s进入minicom设置环境后修改 Serial port setup-> A - Serial Device: /dev/ttyS0
然后保存退出，再运行minicom即可
修改方法2：
[root@colin ~]#minicom
Device /dev/modem access failed.
Then, ls /dev/we found that there is no modem, but ttyS0.Make a soft link and fix this problem.
[root@colin~]#ln -s /dev/ttyS0 /dev/modem
