Panasonic DBS-576HD Technical Manual page 161

Section 700 - Operation
Figure 5-2. Example Directory Number assignments for Extension 200
When a caller originates a call, the call appears on the first available PDN key. If all PDNs are
unavailable, the call will select the EXT LED.
When calls come in to a DN, the call appears on the first available DN key. If the call is to your PDN
and no PDN key is available, the caller hears a busy tone.
Directory numbers may be assigned to FF keys 25-32. These are non-appearing keys.
Intercom voice calls only go to the PDN extension but light the corresponding NPDN keys red. A tone
call follows the appropriate ring status (immediate ring, delayed ring, etc.) for any extension.
576-50-700 DBS 576 (USA) issued September 2001
Chapter 5. Key Telephone Features
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