Can I have ethernet and wireless connections to time capsule?

[rangerstu]

I have a Macbook Pro running Mac OS X 10.6.2 and a 1 TB time capsule. I connect to the internet via a USB 3.5G HSDPA (3G network) direct to my Macbook Pro USB. I have been told that I cannot connect to the internet via the USB connected 3G system at the same time as connecting to the TC via wireless. I guess I have to accept this, although it would have been great to connect to the TC and access the internet either wireless or via ethernet connection.
I have successfully connected the TC to the Macbook Pro via wireless, but I cannot seem to connect via the ethernet connection. When I turn off Airport, with the ethernet cable connected, I lose all connection to the TC. I basically want to connect to the TC by Ethernet and wireless but without the requirement to connect to the internet via a router that is connected to the TC (which is the scenario always catered for in threads and setup guides)

 

[hamlinspahn]

Yes

Yes you can have both but not at the same time. If it isn't working for you it could be as simple as your cable but it is most likely your ethernet settings on your MBP. I could be a TC setting but I would start on the MBP.

 

[rangerstu]

any idea what MBP settings I have incorrect?

Thanks for the advice. I would like the Ethernet to take preference when both the Ethernet and airport are connected. I have adjusted the order of preference in system preferences/network so that Ethernet connection is at the top with AirPort second. I note that AirPort has a green light next to it when it Airport is turned on, but the Ethernet has an orange light with ‘self-assigned IP’. When AirPort is turned off, it has a red light next to it (obviously) but the Ethernet still has an orange light. Could this be the reason the Ethernet does not seem to be working? The TC Ethernet connection shows a solid green light when connected, which I assume means the connection is working correctly. What MB settings do you think I have incorrect?