USB serial on mac os x

Generally you'll be using the same chipset all over - the PL2303
TO get this wokring, you'll need to download the driver from here:

http://sourceforge.net/projects/osx-pl2303/

Then you need the hyperterminal equivalent on Mac OS X, and you can actually run this in screen

If the driver is installed correctly you should have it displayed in dev

ls /dev/tty.*

and get something like this::

$ ls -al tty.*
crw-rw-rw- 1 root wheel 18, 4 Jan 25 07:32 tty.Bluetooth-Modem
crw-rw-rw- 1 root wheel 18, 8 Jan 25 07:32 tty.Bluetooth-PDA-Sync
crw-rw-rw- 1 root wheel 18, 10 Jan 25 09:20 tty.PL2303-0000103D
crw-rw-rw- 1 root wheel 18, 0 Jan 25 07:32 tty.SerialPort-1

then to set the speed you connect:

screen /dev/tty.PL2303-0000103D 9600

Easy Peasy!

Ctrl+A then control , to quit screen