NTAK79 2.0 Mb PRI card
Page 489 of 544
Option 11C and 11C Mini
Technical Reference Guide
Clock controller functions and features
The NTAK79 clock controller functions and features include:
•
phase lock to a reference, generate the 10.24 Mhz system clock, and
distribute it to the CPU through the backplane. Up to two references at a
time may be accepted.
•
provide primary to secondary switchover (auto-recovery is provided)
•
prevent chatter
•
provide error burst detection and correction, holdover, and free running
capabilities
•
comply with 2.0Mb CCITT specifications
•
communicate with software
•
provide jitter filtering
•
make use of an algorithm to aid in detecting crystal aging and to qualify
clocking information
Reference switchover
Switchover may occur in the case of reference degradation or reference
failure. When performance of the reference degrades to a point where the
system clock is no longer allowed to follow the timing signal, then the
reference will be said to be out of specification. If the reference being used is
out of specification and the other reference is still within specification, an
automatic switchover is initiated without software intervention. If both
references are out of specification, the clock controller provides holdover.
Autorecovery and chatter
If the software command “track to primary” is given, the clock controller
tracks to the primary reference and continuously monitors the quality of both
primary and secondary references. If the primary becomes out of
specification, the clock controller automatically tracks to secondary provided
that it is within specifications. On failure (both out of specification), the clock
controller enters the HOLDOVER mode and continuously monitors both
references. An automatic switchover is initiated to the reference that recovers
first. If the secondary recovers first, then the clock controller tracks to the
secondary, but switches over to the primary when the primary recovers. If the
primary recovers first, the clock controller tracks to the primary.
Содержание Meridian 1 Option 11C Mini
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Страница 8: ...Page 8 of 544 Contents 553 3011 100 Standard 14 00 January 2002 ...
Страница 10: ...Page 10 of 544 About this guide 553 3011 100 Standard 14 00 January 2002 ...
Страница 86: ...Page 86 of 544 Memory Storage and CPU capacity 553 3011 100 Standard 14 00 January 2002 ...
Страница 176: ...Page 176 of 544 Transmission parameters 553 3011 100 Standard 14 00 January 2002 ...
Страница 196: ...Page 196 of 544 Spares planning 553 3011 100 Standard 14 00 January 2002 ...
Страница 226: ...Page 226 of 544 System Controller cards 553 3011 100 Standard 14 00 January 2002 ...
Страница 260: ...Page 260 of 544 The TDS DTR card 553 3011 100 Standard 14 00 January 2002 ...
Страница 282: ...Page 282 of 544 M2317 Telephone 553 3011 100 Standard 14 00 January 2002 ...
Страница 308: ...Page 308 of 544 Meridian Modular Telephones 553 3011 100 Standard 14 00 January 2002 ...
Страница 312: ...Page 312 of 544 M3900 telephone series 553 3011 100 Standard 14 00 January 2002 Figure 40 M3901 Figure 41 M3902 ...
Страница 364: ...Page 364 of 544 M2250 Attendant Console 553 3011 100 Standard 14 00 January 2002 ...
Страница 368: ...Page 368 of 544 NT8D02 and NTDK16 Digital Line Cards 553 3011 100 Standard 14 00 January 2002 Figure 55 NTDK16 DLC ...
Страница 388: ...Page 388 of 544 NT8D14 Universal Trunk Card 553 3011 100 Standard 14 00 January 2002 ...
Страница 408: ...Page 408 of 544 NT5K21 XMFC MFE card 553 3011 100 Standard 14 00 January 2002 ...
Страница 414: ...Page 414 of 544 NTAG26 XMFR card 553 3011 100 Standard 14 00 January 2002 ...
Страница 422: ...Page 422 of 544 NT6D71 UILC line card 553 3011 100 Standard 14 00 January 2002 ...
Страница 438: ...Page 438 of 544 NT1R20 Off Premise Station OPS analog line card 553 3011 100 Standard 14 00 January 2002 ...
Страница 492: ...Page 492 of 544 NTAK79 2 0 Mb PRI card 553 3011 100 Standard 14 00 January 2002 ...
Страница 512: ...Page 512 of 544 NTAK20 clock controller 553 3011 100 Standard 14 00 January 2002 ...
Страница 518: ...Page 518 of 544 NTAK93 D channel handler interface 553 3011 100 Standard 14 00 January 2002 ...
Страница 544: ...Page 544 of 544 Index 553 3011 100 Standard 14 00 January 2002 ...
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