Karel DS200, Technical Reference And Installation Manual

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DS Series PBX Technical Reference And Installation Guide
65
VI.3.A.4. THE DCC UTILITY CARD
Definition:
The DCC Utility card is the main unit, which controls the entire DCC functions and which
includes the switching matrix.
The DCC Utility card consists of the Utility motherboard and the PPC CPU card which has
been attached to the motherboard with two connectors that are on the motherboard. The
main processor of the DCC Utility card is the Power PC CPU card.
Technical Information:
Main components of the PPC CPU card are the PPC central processor microchip, a non-
volatile memory (FLASH) of 8MB, a volatile memory (SDRAM) of 32 MB and two 120-pin
motherboard connectors (X1 and X2).
Since the DCC unit has a structure with multiple processors, several different pieces of
software are used in the system. While majority of the pieces of software run on the CPU
card that is on the Utility card, the others run on the slave cards (8E1 cards), which are
installed in the 14 slots that are on the DCC backplane.
A single Utility card suffices for DCC operation. However, a redundant one may be made
available when needed , two Utility cards can be installed in the DCC block. Both cards are
identical in hardware. In case of a malfunction in the functional DCC Utility card, the DCC
automatically shifts to the redundant Utility card. During that transition, no system pause or
data loss occurs.
The DCC Utility card and the redundant DCC Utility card, if available, are supposed to be
installed in the slots in the middle, which are labeled CP1 and CP2 on the DCC backplane.
Master DCC Utility card is installed into the CP1 slot and redundant DCC Utility card is
installed into the CP2 slot.
An RS232 input, a 100 Mbit Ethernet input, a 10 MB Ethernet input and some LEDs are
available on the DCC Utility card. Functions of those LEDs will be explained later in the
document.
The DCC Utility card receives the 48V DC feed voltage from the backplane and generates
the 3.3V DC signal it needs. By this way, the power signals within the DCC block have been
isolated from each other, so that defective units are prevented from adversely affecting other
units.
The card has embedded self-test feature. Thanks to that feature, the DCC Utility card is
capable of testing itself while it is applying BERT ( Bit Error Rate Test) to the E1 channels
within DCC. By this way, any problem that might occur in the future is easily detected in
advance and necessary precautions are taken before system performance deteriorates.
The DCC Utility card can be synchronized with the External clock signal received through
8E1 lines, thanks to the PLL block on it. DCC can transmit the clock signal it receives by that
way to towers of the DS200L system, so that the entire system operates in synchronization
with the External clock signal. The DCC Utility card also has anti-jitter circuits in order to
minimize adverse factors that might be present in the External clock signal, like noise and
jitter.
The DCC Utility card fulfills the tone generation function in order to transmit the tones to
network during direct E1 connections with the External network. Thanks to DSPs on it, it
generates tones like the alerting tone & hold tone and transmits them over E1 lines when
needed.