CHAPTER 3 NDA-24296
Page 464
Revision 1.0
PA-24CCTA
Commo n Channel Trunk

PA-24CCTA

Co mmon C hanne l Trunk

1. General Function
The PA-24CCTA ( 24CC T) circuit ca rd provides an interface between 24 digital trunks and the system at
1.5 M bit/s. Being equipped with a Common Channel Ha ndler (CCH), which can be allocated to a desired
channel among the existing 24 channels by key setting and programming, this card can be used as an inter-
face for a Common Channel I nteroffice Sig naling ( CC IS) syste m. A b uilt-in resonance circuit ca n b e used
for the purpose of extrac ting clock signals when the PBX functions as a PLO-secondary switch. To obtain
appropr iate spee ch le vel, th is c ard is equip ped with a mask R OM in whi ch typical PAD patte rns ha v e been
already written. A desired PAD value can be easily selected by key setting and programming.
Figure 3 -137 Location of PA-24CCTA (2 4CCT) within the System
I/O Local Bus
CPU
System Clock
INT TSW INT
Common Channel Signaling Link
PLO
1.544 MHz Clock Extraction
(For PLO-secondary switch)
CCH
Built-in Common Channel Handler (x1)
T
R
24CCT
: Common Channel Signaling Link
: Speech Path (PCM Signal)
: Clock Signal
CCIS
NETWORK