Adtran express 3000 User Guide
Chapter 7. Installing an Analog Modem
61203153L2-20
Express 3000 User Manual
7-5
CONTROLLING AN EXTERNAL ANALOG
MODEM
MODEM
You can enable and disable (control) an external modem with the Win-
dows 95/98 Tray Tool Menu (see Launching the Tray Tool on page 3-3)
or with VT-100 terminal emulation (discussed here). When the
Express 3000 enables the external modem port, the external analog
modem RTS and CTS lines directly switch over to the PC COM port.
This switching process allows the external analog modem to provide
flow control as normal. Once the modem is enabled, all further COM
activity transmits to the external analog modem. When the modem is
disabled, the ISDN terminal adapter within the Express 3000 process-
es all further COM port activity.
dows 95/98 Tray Tool Menu (see Launching the Tray Tool on page 3-3)
or with VT-100 terminal emulation (discussed here). When the
Express 3000 enables the external modem port, the external analog
modem RTS and CTS lines directly switch over to the PC COM port.
This switching process allows the external analog modem to provide
flow control as normal. Once the modem is enabled, all further COM
activity transmits to the external analog modem. When the modem is
disabled, the ISDN terminal adapter within the Express 3000 process-
es all further COM port activity.
Controlling the Modem via Terminal Emulation
Another method of controlling an external analog modem is using a
VT-100 terminal emulation package such as HyperTerminal. First, de-
termine if the external analog modem is properly connected to the
Express 3000 by typing the AT command
VT-100 terminal emulation package such as HyperTerminal. First, de-
termine if the external analog modem is properly connected to the
Express 3000 by typing the AT command
AT!Z
and pressing the
Enter
key. If properly connected, the Express 3000 responds with the mes-
sage
sage
MODEM FOUND
. If the external analog modem is not properly
connected, the Express 3000 responds with the message
NO MODEM
FOUND
.
Command
Function
AT_L1 <cr>
Enables external analog modem.
AT <cr>
OK response (sets modem baud rate).
ATI <cr>
Identifies the modem (verifies modem connected).
AT&C1 <cr>
Sets CD to normal.
AT&W <cr>
Saves settings.
AT_L0 <cr>
Disables external analog modem.
The
AT!Z
command is directed to the Express 3000, not the
analog modem itself. An
ERROR
occurs if the command is
sent while the external analog modem is enabled.