Filter
Top Products
99
C
Appendix C
AT Commands
AT Commands
This Appendix details the "AT" commands used by modems and ISDN TAs. This information
is provided to assist users who are using the serial port of LevelOne WBR-1100TX.
It is not relevant to Cable or DSL modems connected to the WAN (Ethernet) port.
Required Settings
For the LevelOne Wireless Broadband Router to use the Serial Port correctly, the modem or
ISDN TA must be set as follows.
Setting AT Command
Fixed baud rate setting AT&B1
RTS/CTS flow control AT&K3
DCD to track the presence of a carrier AT&C1
DTR off to hang-up modem AT&D2
DSR always on AT&S0
If your Modem or ISDN TA uses the commands above, then the Initial String would be as
follows:
AT&F&B1&K3&C1&D2&S0X4
Notes:
• The command "AT&F" is used to set the modem to the factory default settings, to ensure a
consistent starting point.
• For some Mircocom and other modems, the "ATX4" command is not sufficient - a "W2"
command (no "AT") must be used as well.
• ISDN TAs may not use these commands; please check your user guide for your ISDN TA.
Finding the current Initial String
If your modem or ISDN TA is already working correctly using the PC's serial port, but you
don’t know what the initialization string is, you can use the following procedure to find out.
1. Select My Computer, then Dial-Up Networking.
2. Select the icon for your connection, then Properties.
3. Click the Configure button, then the Connection tab, as shown below.