Find out what /dev/cuaU maps to?

Question

I have an USB 3G modem (Huawei E353-u2) on pfSense 2.0.2 (which is based on FreeBSD 8.1-RELEASE-p13), it seems to create 2 /dev/cuaU devices:

/dev/cuaU0.0
/dev/cuaU0.3

1) Why are there 2 devices? Is one of them maybe the usb mass storage of the stick?

2) On the OS level (shell), how can I find out which of those 2 devices is the "real modem" / to what /dev/cuaUx.y is mapped?

Thanks for any hint :-)

Answer 1

Web search suggests this modem knows AT command set, so you can easily check this using "tip" or "cu" commands with both ports and detect which one responds to AT.