Install minicom using the following command
sudo apt-get install minicom
Now you need to check your serial ports using the following command from your terminal
You should see similar to the following output
[ 1.430818] serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
[ 1.431528] 00:0c: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
This means the device correspond to my serial port is ttyS0.
Configure minicom using the following command
sudo minicom -s
Use the keyboard keys to select the menu item Serial port setup.
Enter A to change the Serial Device to /dev/ttyS0, and then enter E to change the line speed to 9600 8N1
Using arrow keys, select Save setup as dfl
Select Exit from Minicom.
Next time, from the terminal you only need to run sudo minicom in order to access your Cisco box or you make the user a member of the ‘dialout' group. Then you don't have to run minicom with sudo after the initial default configuration. The Dialout group owns all of the serial ports in Ubuntu.