OBDII serial/usb/applescript questions Carputer

This is a synopsis of whats going on in my head and at anothr forum.

OBDII the serial interface used by cars, has something called ScanTool that is a device with accompanying software to display the data.

There is no OSX software of course.

I know there exists an applescript thing for communicating with a serial/usb device (the ScanTool is serial, run it thru a USB adapter for mac)

the question I have, since Im new totally to scripting, where do I see this inflow of data from the device on screen? Like I connect the device to a mac, turn the car on and want to see some sort of data start to flow.

How do I begin to get the data on screen so I can manipulate it into various real-time graphs etc?