18 — RS-232 DCM
2902 MainStreet Technical Practices
18-9
May 2002 90-2906-01
If you are experiencing high bit error rates due to a combination of interface speed,
cable length and DCM clocking configurations, try inverting the receive clock
(RX_INV).
Procedure 18-7 To configure clocking
The INTERNAL softkey is not available when transparent rate adaption is selected.
where
pp
is 1 or 9, and
c
is 1 or 2
* Default
18.10
Multidrop data bridge
In a multidrop data bridge, several broadcast destination circuits (called slaves) take
turns using the same bandwidth to communicate with one broadcast source circuit
(called the master); for example, several terminals would take turns communicating
with a host computer. The master device controls the use of the shared bandwidth by
polling each slave in turn. Figure 18-2 shows a multidrop data bridge.
Figure 18-2 Multidrop data bridge
To create a multidrop bridge, two components are needed: a data interface that
supports the multidrop function and a multidrop data bridge. The 2902 MainStreet
unit supports the multidrop interfaces but does not provide the multidrop data bridge.
One way to use a 2902 MainStreet unit in this type of application is in conjunction
with a 3600 MainStreet Multiservice Bandwidth Manager containing a Sub-Rate
Interface module (SRM).
RX_INV
/NO_RX_INV*
INTERNAL EXTERNAL
LOCKED*
/INDEPNT
SLAVE*
CONFIG — CIRCUIT — <
pp-c
>
↵
— FUNCTION — CLOCKING
SK000506
Slave
devices
Master
device
Branch
circuits
Aggregate
circuit
2285
Polling
Responding
Multidrop
data bridge
Summary of Contents for MainStreet 2902
Page 1: ...2902 MainStreet Network Termination Unit Release 1 0 H T E C H N I C A L P R A C T I C E S ...
Page 40: ...3 Mounting the unit 3 8 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 50: ...4 Ground and power connections 4 10 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 68: ...6 Connecting to the network 6 4 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 90: ...7 Connecting to data devices 7 22 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 108: ...10 Node management 10 10 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 150: ...14 CPSS 14 6 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 218: ...20 Codirectional DCM 20 6 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 234: ...22 HCM rate adaption 22 10 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 246: ...23 Cross connecting circuits 23 12 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 254: ...24 Visual indicators 24 8 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 266: ...25 Alarms 25 12 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 278: ...26 System diagnostics 26 12 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 298: ...27 Loopbacks 27 20 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 332: ...Glossary GL 8 2902 MainStreet Technical Practices 90 2906 01 May 2002 ...
Page 343: ......
Page 344: ... 2002 Alcatel All rights reserved 90 2906 01 95 1820 01 00 C ...