Chapter 7. SLT Features
FF1-0-03: Extension COS (Intercom Redialing)
FF3: Extension COS
Extension Class of Service (COS) determines whether Last Number Redial can be used for both
intercom and CO calls or CO calls only.
CPC-96, CPC-288, and CPC-576 All Versions
Offhook Signaling sends a tone over the handset to a busy extension to indicate that a CO call has
arrived or a call is camped-on.
After receiving an offhook signal during a call:
1. Complete the first call and place the handset on hook.
2. After the telephone rings, go off hook.
FF3: CO Off-Hook Signal
FF1-1: Off-Hook Signal Timer
The CO call type may be either multiple ring, or DID/DIL whose destination is set to Auto camp-
on (Call Waiting).
Offhook signaling is not supported for an ISDN terminal.
The System does not send the offhook signal under the following conditions:
• During a conference call
• During an OHVA or Busy override
• Data Privacy is enabled
• Receiving telephone is a 3rd party voice mail.
DBS 576 (USA), issued January 1999
Section 700 - Operation