Controlling The Modem - Ericsson ZAT 19.2 Operation Manual

2.3.4 Controlling the modem
The modem may be in either command status or modem status.
When the modem is in command status, this means that it is
ready to receive commands from your keyboard. When it is in
modem status, it is connected to the telephone line and all data
from the terminal ts transmitted over the telephone network to a
remote modem.
When the power supply is switched on, the modem will always
initially be in the command status. This should be the situation at
the present moment.
Enter AT on the keyboard followed by <Return>. The characters
«AT» should now appear on the screen. This is an «echo» from
the modem, an acknowledgement that contact has been made.
On the next line the modem will now give the message OK. This
signifies that it is now ready to receive further commands.
"If this does not occur, turn to the section « Trouble-
shooting» and read the section «Modem dead». When
you have found the problem - and solved it, return to this
point.