368 NT5K21 XMFC/MFE card
Digit Forward direction
OG-Tx, IC-Rx Backward direction
4700 Hz + 1300 Hz —
5900 Hz + 1300 Hz —
61100 Hz + 1300 Hz —
7700 Hz + 1500 Hz —
8900 Hz + 1500 Hz —
91100 Hz + 1500 Hz —
10 1300 Hz + 1500 Hz —
Sender and receiver mode
The XMFC/MFE circuit card provides the interface between the system’s
CPU and the trunk circuit which uses MFC or MFE signaling.
The XMFC/MFE circuit card transmits and receives forward and backward
signals simultaneously on two channels. Each channel is programmed like
a peripheral circuit card unit, with its own sending and receiving timeslots
in the network.

Receive mode

When in receive mode, the XMFC/MFE card is linked to the trunk card by
a PCM speech path over the network cards. MFC signals coming in over
the trunks are relayed to the XMFC/MFE card as though they were speech.
The XMFC/MFC card interprets each tone pair and sends the information
to the CPU through the CPU bus.

Send mode

When in send mode, the CPU sends data to the XMFC/MFE card through
the CPU bus. The CPU tells the XMFC/MFE card which tone pairs to send
and the XMFC/MFE card generates the required tones and sends them
to the trunk over the PCM network speech path. The trunk transmits the
tones to the far end.

XMFC sender and receiver specifications

Table165 "XMFC sender specifications" (page 369) and Table 166 "XMFC
receiver specifications" (page 369) provide the operating requirements for
the NT5K21 XMFC/MFE card. These specifications conform to CCITT R2
recommendations: Q.441, Q.442, Q.451, Q.454, and Q.455.
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright© 2003-2008, Nor tel Networks
.