Which card do you have, a WIC-1T or a WIC-1DSU-T1?
If a WIC-1T, then you need an external CSU/DSU.
If a WIC-1DSU-T1, then your configuration will look something like:
Interface serial 0/0
service-module t1 clock source internal
service-module t1 timeslots 1-4 speed 64
service-module t1 framing esf
service-module t1 linecode b8zs
ip address 10.1.1.1 255.255.255.0
encapsulation ppp
fair-que
no shut
You may have to adjust the clock, timeslots, framing, linecode, and/or encaps to fit your unique circuit.