User`s manual

U.S. Robotics I-modem Command Reference
Dialing, Answering, and Hanging Up • Page 3-1
Chapter 3
Dialing, Answering, and Hanging Up
I-modems always make and receive calls over ISDN lines. Everyday actions, such as dial-
ing and answering, are done differently over ISDN than they are over analog lines.
For instance, analog dialing is done by sending tones or pulses over the line. ISDN devices
dial by sending digital signals over the line. Also, your analog phone rings because it
receives a burst of voltage through the line. ISDN devices know they are receiving a call
when they receive digital signals.
Despite the differences between analog and ISDN calling, you should not notice any
change in the way you make or receive calls using I-modems. You can use commands just
as you would when making analog calls using a modem.
Dialing
Dn Dial the speciÞed phone number and execute dial options.
Note With the exception of the following Dial options, I-modems ignore any
commands issued after the D in the same command string.