ADTRAN 3000 - Manual (Page 88)

Chapter 7. Installing an Analog Modem
7-6 Express 3000 User Manual 61203153L2-20
When carrier detect (CD) is active (i.e., a call is connected) on the ex-
ternal analog modem, the Express 3000 will not switch control from
the modem port when you attempt to disable it. The call must be
hung-up (disconnected) to deactivate CD, before you can switch con-
trol from the modem port and disable it.
INTERNAL ANALOG MODEM APPLICATION
The following items are necessary to connect an internal analog mo-
dem to the Express 3000:
• Internal analog modem
• RJ-11 to RJ-11 telephone cable
When using an internal analog modem with the Express 3000, two
COM ports are assigned on the PC and configured independently. See
the manufacturer's documentation for internal analog modem config-
uration.
Figure 7-2 on page 7-7 illustrates the connections for installing an in-
ternal modem to the Express 3000.
Using VT-100 Terminal Emulation to Enable/Disable the Modem
To do this... Enter this AT Command
Enable modem AT_L1 and press the Enter key
Disable modem AT_L0 and press the Enter key