AT&T System 25 - Manual (Page 21)

Data Calls
Placed from Your Telephone
If your System Administrator has assigned a button to
your telephone, you can use it to place data calls for your
associated data terminal.
Placing a Data Call
1
2
3
4
5
6
7
Turn on your data terminal.
Lift the handset on the associated telephone and listen for
dial tone.
If your data call is an inside call, dial the DDC and go to
Step 4.
or
If your data call is an outside call, press
Dial the data number.
.
Listen for a high pitched answer tone and complete any
additional necessary dialing.
Press within 15 seconds of hearing answer tone.
Hang up and go to the data terminal.
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