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

/dev/tty00 is the serial port, while 9600 sets its baud rate to 9600bps.

CTS/RTS handshake

screen /dev/tty00 9600,ctsrts

close connection

Ctrl + A + k

serial port status

Ctrl + A + i