Tadiran Telecom Coral IPx 500, Installation Manual

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Shared Service Ports
9-39
DTMF Receiver (DTR)
9
9.7
DTMF Receiver (DTR)
The MSBipx includes the DTR circuits. The DTR provides eight circuits, which receive
and decode Dual Tone Multi-Frequency (DTMF) dialing tones. The DTR is required to
support telephone station apparatus or trunks that send DTMF tones to the Coral IPx
500 system to activate system features or select other ports.
DTMF signaling is commonly used by industry standard, single line telephone (SLT)
sets, as well as E&M tie trunks and Direct Inward Dialing (DID) central office trunks.
Loop-start and ground-start central office trunks, which are defined in the system
database as IRSS (Freedom) or DISA, require a DTR to be installed in the system.
The DTR uses industry standard DTMF receiver circuitry to decode DTMF dialing
tones. The audio side of each DTMF receiver circuit is directly coupled through a
CODEC to the Pulse Code Modulation (PCM) switching matrix of the Coral IPx 500
system. Decoded digital data is passed through the peripheral bus to the system
processor.
When the DTR exists and initialized, the PI displays the following:
8DRCF in (Route: CLIS) Shelf #0, Slot #13, in the P_TYPE field.
DTR in (Route: PLIS) Shelf #0, Slot #13, Ckt #0-7 in the TYPE field.
Refer to the Program Interface (PI) and Database Reference Manual - Chapter 6 for further
details
1 General Description