Switch Matrix Card; Facilities; Dxarray; Ringing Reference Generator - Mitel SX-200 Manual

22. SWITCH MATRIX CARD

Facilities

DX Array

Ringing Reference Generator

Non-volatile
22.01 The Switch Matrix Card resides in a dedicated card slot directly
to the right of the MCC in the control bay of the 672-port
SX-200 DIGITAL PABX. It expands the DX switching matrix, the static
non-volatile RAM, and the resources of the 7720 Digital Signal Proces-
sor. The card measures approximately 325 mm x 366 mm (12.8" x
14.4").
22.02 The Switch Matrix card provides:
24 x 24 link DX array
Digital Signal Processor
l
Dial Tone Filter
Ringing Reference
8 Kbytes Non-volatile Static RAM
22.03 The DX Array on the Switch Matrix Card consists of a 24 x 24
link switching array provided by 9 Mite1 DX chips with balanced
drivers and receivers.
22.04 The Digital Signal Processor generates PCM data corresponding
to a 20Hz sine wave, which is passed through the DX array. A
filtered and distributed via the backplane to the Bay PSU, which con-
tains a ringing amplifier.
Static RAM
22.05 Any time the user enables a function the changed data
(extension number, type of forwarding) must be saved in a
non-volatile memory so that it is not lost on power down or system
failure. The Static RAM acts as a buffer for this sort of data. As the
data accumulates, finally filling up the buffer, it is then transferred to
disk. This reduces disk running time, increasing the disk drive's life-
span. During power-off periods, the static RAM is powered from a
large capacitor, providing
THE SWITCH MATRIX CARD MUST NOT BE INSERTED OR REMOVED
WITH THE POWER ON. DAMAGE TO ONBOARD
SULT.
Circuit
Generator
72-hour holdover time.
WARNING
Card Descriptions
CIRCUITS MAY RE-
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