AT&T MERLIN LEGEND Release 2.0 Data User's Manual page 41

Making and Answering Data Calls
Make sure you have the telephone number of the analog data
station you are calling.
NOTE:
For analog data stations, you must enter a pause (,) in the
dialing sequence to ensure that the system has time to
access an outside line.
For example, if the dial-out code is 9 and the number you
are calling is 555-1212, you would enter on your terminal
keyboard:
using the comma to insert a pause.
When dial ing from an analog multiline telephone, you dial
the dial-out code and wait for dial tone before proceeding
to dial the number.
9,5551212
Making Analog Data Calls
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