Printed Circuit Boards; Digital Telephones - Toshiba Strata DK24 Installation And Maintenance Manual

INSTALLATION-SYSTEM DESCRIPTION
SECTION 400-096-202
SEPTEMBER 1992
phones, electronic telephones, standard tele-
phones, and most peripherals.
•
Modular: Modular jacks connect CO lines, E &
M TIE lines, the Station Message Detail Record-
ing port (RS-232 signaling), and the Remote
Administration and Maintenance port (RS-232
signaling).
•
Terminals: Screw terminals connect the op-
tional customer-provided Music-on-Hold/Back-
ground Music source to the PCTU or PCTUS,
and spring-clip terminals connect peripherals to
the PIOUS.

6.10 Printed Circuit Boards

6.11 The following paragraphs provide functional
descriptions, along with applicable configuration
and connection details, for all PCBs available for
installation in STRATA DK systems. Refer to Fig-
ure 2-10 for a pictorial overview of each PCB's
peripheral connections.
PCTU (Common Control Unit): The PCTU is the
system controller PCB that is available in four
different releases: PCTU1 is equipped with Re-
lease 1 software, PCTU2 with Release 2 soft-
ware, PCTU3 with Release 3 software, and
PCTU4 with Release 4 software. The PCTU
must be installed in DK56 and DK96, and it or the
PCTUS (see "PCTUS" description that follows)
must be installed in the DK24. The PCTU con-
tains the system's main microprocessor and
microprocessor bus, battery-protected memory
circuits, time switch logic, conference logic, and
system tones. The PCTU also has a Music-on-
Hold/Background Music source interface and
connectors to mount an optional DTMF receiver
PCB (CRCU) for DISA, TIE lines, standard tele-
phones and peripherals. See Table 2-B for more
PCTU details.
PCTUS (Common Control Unit): The PCTUS is a
reduced version of the PCTU and is intended for
the STRATA DK24 only. Providing the Release
2 software feature set, the PCTUS supports
fewer universal slots, stations, and CO lines
than the PCTU. See Table 2-B for more PCTUS
details.
CRCU (Dual-tone Multi-frequency (DTMF) Re-
ceiver Subassembly): The CRCU is an op-
tional DTMF receiver PCB which mounts on the
PCTU or PCTUS "piggyback" style. It translates
DTMF signals from Direct Inward System Ac-
cess (DISA) CO lines, TIE lines, standard tele-
phones, or peripheral devices into data signals
for the STRATA DK system. The system will not
receive DTMF dialing without the CRCU. The
DTMF receivers are shared by users; they are
seized for dialing, then released for the next
call. Both 4-circuit (CRCU-4) and 8-circuit
(CRCU-8) units are available. The CRCU-8 is
designed for systems with heavy traffic, the
CRCU-4 for systems with lighter traffic.
PDKU (Digital Telephone Interface Unit): Avail-
able with Release 3 and higher software, the
PDKU provides eight circuits that can support
data interface units (DIUs), a digital door phone/
lock control unit (DDCB), and a digital direct
station selection console (DDSS) as well as
digital telephones. (The DDCB is only available
with Release 4.)
NOTE:
The new PDKU2 and the older PDKU1 are
identical, except that only PDKU1 circuits 1 ~
7 can support data interface units, while all
PDKU2 circuits (1 ~ 8) can support these
units. Both PDKU versions are completely
compatible and can be mixed in the system.
PIOU (Option Interface Unit): The PIOU pro-
vides a circuit interface with the peripheral
options listed in Table 2-C.
PIOUS (Option Interface Unit): A reduced ver-
sion of the PIOU, the PIOUS provides a circuit
interface with the peripheral options listed in
Table 2-C.
IMDU (Remote Maintenance Modem Subas-
sembly): The IMDU is an optional built-in mo-
dem that can be attached to the PIOU or PIOUS
to provide the system with a link to off-site
programming and maintenance equipment,
such as a personal computer or ASCII terminal.
The IMDU has an internal maintenance chan-
2-8