User`s manual

U.S. Robotics I-modem Command Reference
Troubleshooting • Page 15-4
The I-modem wonÕt dial
Check your communications softwareÕs manual to Þnd out which Data Terminal Ready
(DTR) setting it requires. You may need to change the DTR setting at the I-modem. If so,
see Chapter 6, Controlling EIA-232 Signaling
.
Hear ringing, but the I-modem wonÕt answer
¥ Check your communications softwareÕs manual to Þnd out what DTR operations your
software requires. Also, for external I-modems, look at the TR LED to make sure your
terminal or computer is sending a DTR signal via the EIA-232 interface.
¥ Send ATI4 to the I-modem and check that S0 is set to a value higher than 0.
¥ Set &F and S0=1, then try again.
The I-modem acts as though a data link has been established, but no call was
received,
Carrier Detect (CD) may be overridden (with &C0), but your system may require that the
override be turned OFF (with &C1). Review your communications software manual to see
what CD operations are required.