connect screen to a serial interface
If you didn't have kermit or minicom on your system, you can use screen to connect to your serial port.
Open the connection with the correct baudrate
screen /dev/tty00 9600
screen /dev/ttyS0 9600
is the serial port, while 9600 sets its baud rate to 9600bps.
screen /dev/tty00 9600,ctsrts
Ctrl + A + k
serial port status
Ctrl + A + i