In Linux, you can use the setserial
command, as root, to view/change the serial port parameters. In your case, this would appear to be /dev/ttyS0 and /dev/ttyS1.
In a terminal, use man setserial
to read the manual
Of course, you don't actually connect to
the serial port itself, you communicate with whatever device is attached to the serial port. If you look at the ownership of /dev/ttyS0, you will see that it is owned by root and the associated group is dialout.
BASH:~/-> ls -l /dev/ttyS*
crw-rw----. 1 root dialout 4, 64 2011-06-07 09:16 /dev/ttyS0
crw-rw----. 1 root dialout 4, 65 2011-06-07 09:16 /dev/ttyS1
crw-rw----. 1 root dialout 4, 66 2011-06-07 09:16 /dev/ttyS2
crw-rw----. 1 root dialout 4, 67 2011-06-07 09:16 /dev/ttyS3
You can always use the serial port(s) as root, but if you should want to use it/them as a regular user, the easiest way is to add your regular user to the "dialout" group.
Also, maybe a brief explanation of what you're trying to use the serial port for would help us help you.