MiniCom
To run minicom to test a usb/serial port you should first kill the Luup engine, the serial proxy, and Network Monitor which reboots Vera when it detects the Luup engine isn't running. Do this by running these 2 commands:
kill $(ps ax | grep 'Start_serproxy.sh.$\|Start_serproxy.sh$\|Start_LuaUPnP.sh$\|Start_LuaUPnP.sh.$\|Start_NetworkMonitor.sh$\|Start_NetworkMonitor.sh.$')
killall LuaUPnP NetworkMonitor serproxy
Next, download the minicom package and extract the minicom program with the commands below. Afterwards you can setup and start using minicom by running /tmp/minicom/usr/sbin/minicom -s and specifying the port options:
mkdir /tmp/minicom
cd /tmp/minicom
wget -O /tmp/minicom.ipk http://downloads.x-wrt.org/xwrt/kamikaze/snapshots/brcm-2.4/packages/minicom_2.3-1_mipsel.ipk
tar zxvf /tmp/minicom.ipk
tar zxvf data.tar.gz