User`s manual

U.S. Robotics I-modem Command Reference
Dialing, Answering, and Hanging Up • Page 3-9
Call Detection
I-modems support Call Detection, which allows them to recognize whether an incoming
call is analog data, Fax Class 1, or Fax Class 2.0. It is especially useful for BBSs because
it automates recognition of different calls from multiple users.
Call Detection is an optional Service Class 2.0 feature and is also implemented by U.S.
Robotics for Fax Class 1 applications.
To obtain a copy of the technical speciÞcation of U.S. Robotics' implementation of Call
Detection for Fax Class 1, call our BBS at the number provided on the Customer Support
Services card included with your multiport I-modem and download the Þle
CALLSEL.TXT.
For information on implementing Fax Class 2.0 Call Detection, see the standard listed
above.