Isdn Communication Basics; Understanding At Commands - ZyXEL Communications ACCESSING INTERNET & INTRANET omni series User Manual

5
ISDN Communication
Basics
In this chapter, we will cover how to initiate and receive calls over
digital lines using your TA.

Understanding AT Commands

AT commands are used to configure and control the omni. Command
statements are usually sent to the TA by being typed from the
computer keyboard.
Command statements must be written in a specific form in order for
the TA to recognize them. A command statement begins with the
letters "AT" or "at". It is then followed by one or more commands
and then by <Enter>.
AT commands can only be issued when the TA is in "command" or
"off-line" mode.
Once the TA has established a connection with the remote device, it
goes into "on-line" mode, and the characters sent from your
computer (through the TA) are transmitted to the remote device.
In order to issue an AT command statement, you first need to run
your communications software and configure it to the port connected
to the TA. Refer to your communications software manual if this is
not the case.
Once the communication terminal program is running and the TA is
connected:
Type:
AT<Enter>
TA responds:
OK

ISDN Communication Basics 25