How to assign DID (Direct Inbond Dial) (dummy) to analog FXO

I am using asterisk 1.4, Dahdi, sangoma 2port FXO.

I want to set DID for each FXO channel. I know analog PORTS line does not Generate DID, but I read on web that its possible
How to pass dummy DID for each FXO channel using Asterisk 1.4. Which file should I edit or configure.
Note: I am not using any GUI client for asterisk