Call Waiting Indication combines two functions:
- "Call Waiting (CW)" can be enabled ("on", "visual only", "ringer") or disabled ("off"). This function allows the phone to receive more than one call at one time.
- "Call Waiting Indication (CWI)" If Call Waiting is enabled ("on", "visual only", "ringer") the incoming caller extension is displayed in the lower left corner of the display. A short knocking signal can be heard simultaneously in the background of your current active call indicating another incoming call.
Starting with 10.1.33.33 by disabling ("off") Call Waiting the phone will send 486 "Busy Here" also for Dial screen is active (user lifted the handset or started Dialing from Idle) and the call attempt is started (Invite send, Ringback received etc.) In older versions, CW "off" was only covering established calls.
- on -> Visual and audio indication of incoming calls that are waiting
- visual -> Visual indication but NO audio indication
- ringer -> Audio indication but NO visual indication
- off -> Disabled and only ONE call can be received and handled at a time
for PA1 = on
for PA1+ = off