User`s manual

U.S. Robotics I-modem Command Reference
Using the AT Command Set • Page 1-10
Getting a List of S-registers
To display a list of S-registers, issue the following command while in T
erminal mode:
ATS$ <Enter>
Also, the command ATI5 displays the values of the S-registers as part of the listing of
NVRAM's contents.
More command lists are available. (See Chapter 13, Displaying Help Screens
.)