Looking at 2820vn - excuse any incorrect terminology, its mostly witchcraft to me!

What I want is a single PSTN line to connect to FXO port and then any incoming calls to be 'transferred' to an Asterisk based PBX via SIP.

(PBX may be on internal network or hosted yet, not sure - guess it shouldn't matter?)

Does this make sense, can 2820vn do this?