Appendix Cat Commands; At Commands - LevelOne WBR-1101TX User Manual

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 LevelOne WBR-1101TX's serial (RS232 port).
It is not relevant to Cable or DSL modems connected to the WAN (Ethernet) port.
Required Settings
For the LevelOne WBR-1101TX to use the Serial Port correctly, the modem or ISDN TA must
be set as follows.
Setting
Fixed baud rate setting
RTS/CTS flow control
DCD to track the presence of a carrier
DTR off to hang-up modem
DSR always on
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.
AT Command
AT&B1
AT&K3
AT&C1
AT&D2
AT&S0
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