The base firmware will do this, but you may want to update it to the latest version. It's locked at 125kbps at the moment, as I'm working on automatic baud rate detection.
Out of the box your until will be locked at 125kbps. But you can connect it to a CAN network and send the dump command over USB serial and it will display the packets.
Check out my post here:http://forum.canb.us/discussion/43/serial-commands#latest