Technical Reference for ZyXEL omni.net series
4-1
Chapter 4
ISDN Communication Basics
This chapter covers how to initiate and receive calls over digital lines using your ZyXEL omni.net
ISDN TA.
Understanding AT Commands
AT commands are used to configure and control the omni.net by typing the command statements at
the computer or terminal keyboard. Command statements must be written in a specific form in
order for the omni.net to recognize them. A command statement begins with the letters string [
AT]
or [
at
], followed by one or more alphanumeric commands (a set of letters and numbers) and then
ended by pressing <Enter>, as shown in the following examples.
Examples of AT Commands
Type
AT Command
Operation
omni.net
Response
AT<Enter>
To verify that the omni.net is
online with your terminal or
computer.
OK
ATCL?<Enter>
To inquire about the current
setting of the packet length or
frame size.
Maximum user data length in packet:
Table 19. Examples of AT Commands
AT commands can only be issued when the omni.net is in command or off-line mode.
Once the omni.net has established a connection with the remote device, it goes into on-line mode,
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