I thought that I had already documented this but it appears not, something I get asked now and again is how to access serial devices using the Linux terminal, a perfect example of this is older Lights out Management modules. The answer is Screen.
screen /dev/SERIALPORT 9600 8N1
Just replace serial port with either your port name or adapter and your all set, you can also adjust the baud rate or change the bits if needed.
Not difficult just handy