CMX602BD4 MX-COM, Inc., CMX602BD4 Datasheet - Page 13

• Manufacturer Part Number: CMX602BD4
• Description: Calling line identifier plus call waiting
• Manufacturer: MX-COM, Inc.

Calling Line Identifier plus Call Waiting (Type II)
5.1.2 British Telecom System
Figure 12 illustrates the line signaling and CMX602B input and output signals for the British Telecom 'On-
Hook' Caller ID system as defined in the British Telecom specifications SIN227 and SIN242 part 1. A similar
system is described in ETSI 300 659-1 Section 6.1.2c.
The Tone Alert signal consists of simultaneous 2130Hz and 2750Hz tones. The 'Chan Seize' signal consists
of a '1010..' FSK bit sequence. Not shown are the requirements for AC and DC loads, including a short initial
Current Wetting Pulse, to be applied to the line 20ms after the end of the Tone Alert signal and to be
maintained during reception of the FSK signal.
Note: For simplicity of presentation, the Data Retiming function is not used in Figure 12 (RXCLK is kept high).
5.1.3 Other 'On-Hook' Systems
ETS 300 659-1 also allows for systems where the FSK transmission is preceded by a Dual Tone Alert signal
similar to that used by British Telecom but without line reversal (ETS 300 659-1 Section 6.1.2a) or by a
Ringing Pulse alerting Signal (ETS 300 659-1 Section 6.1.2b).
The U.K. CCA (Cable Communications Association) specification TW/P&E/312 precedes the FSK signals by
a 200 to 450ms ring burst. AC and DC line terminations during FSK reception are optional.
Mercury Communications Ltd. Specification MNR 19 allows for either the British Telecom system or that
specified by CCA.
As these are all slight variants on the Bellcore and British Telecom systems, they can also be supported by
the CMX602B.
4800 Bethania Station Road, Winston-Salem, NC 27105-1201, USA
SIGNALING
2000 MX-COM, Inc
LINE
[1] IDLE 1 + IDLE 2
[2]
MODE
IRQ
RXD
DET
IRQ
RD
RT
ZP
may go low at end of DET high period, but this is not guaranteed.
reversal
Line
5 sec.
4.8 sec
IDLE 1
www.mxcom.com Tel: [phone] 744 5050 Fax: [phone]
100ms
[1]
Figure 12: British Telecom System Signals
88-110ms
ALERT
TONE
4.8 sec
IDLE 2
45ms
[2]
[1]
13
80-262ms
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CHAN
SEIZE
FSK IDLE
FSK IDLE
45-75ms
MARK
CMX602B PRELIMINARY INFORMATION
MESSAGE
2.5 sec
FSK DATA
FSK DATA
Doc. # 20480204.002
200ms
RINGING