Cisco BPX 8650, Installation And Configuration Manual

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Cisco BPX 8600 Series Installation and Configuration
Release 9.3.30, Part Number 78-12907-01 Rev. E0, May 2005
Chapter 15 Connecting Temporary Terminal and Attaching Peripherals
Making External Clock Connections
Figure 15-6 Dial Modem Cabling for Auto Dial (dial-out to customer service)
Making External Clock Connections
If you want to synchronize the BPX switch to some other external equipment or a local digital central
office, you can use one of two connectors on an BCC15-BC or BPX-BCC-3-BC back card shown in
Figure 15-7 to accept a clock input.
You can use a DB15 connector labeled EXT TMG to connect a balanced T1 or E1 signal, which is
synchronized from some higher-level source to the BPX switch. If an unbalanced 75-ohm E1 signal is
available as the timing source, a BNC EXT TMG connector is also provided.
For a BCC-3-BC back card (back card for BCC-3-32M, BCC-3-64M, or BCC-4V), you can use a DB15
connector labeled EXT 1 TMG to connect a balanced T1 or E1 signal, which is synchronized from some
higher-level source to the BPX switch.
The EXT 2 TMG connector provides a redundant connector to EXT 1 TMG. A T1 source with 100 ohm
impedance or an E1 source with 100/120 ohm impedance typically uses this connector. If an unbalanced
75-ohm E1 signal is available as the timing source, a BNC EXT TMG connector is also provided.
The BPX switch can use these inputs rather than its internal Stratum 3 clock source.
Note
Contact Cisco Customer Service for information on setting up either a 75-ohm or 120-ohm clock
interface on the BCC back card.
Auxillary
port
Modem
connector
1
2
3
4
5
6
20
7
1
2
3
4
5
8
20
7
CD
FG
TXD
RXD
RTS
CTS
DSR
DTR
SG
Legend
FG - Frame Ground
TXD - Transmit Data
RXD - Receive Data
RTS - Request To Send
CTS - Clear To Send
DSR - Data Set Ready
DTR - Data Terminal Ready
CD
- Carrier Detect
SG - Signal Ground
Note: Cable must be connected in direction shown from node
to modem because wiring is not pin-to-pin symmetrical.
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