Data sheet, E1- attachment – Procom E1 Attachment User Manual

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Data Sheet

E1- Attachment

E1 Attachment for 4FTR and LCPU

Clock Synchronization

If one connects independent systems over E1, transmission errors are to be
expected because of the unsynchronized clocking. An input buffer on the E1
attachments establishes a controlled frame slip.
This results in loss of a sampled value and goes unnoticed in purely voice
applications.
Control data is reconstructed by the data link layer.
To optimize the system performance synchronization should be done if possible.
Synchronization is done by the CPU1.

The DVS-21 can be combined together into a group in various ways.

- DVS-21 master / slave operation

Example 1: Clock extraction from transmission network (e.g. railway network). All devices are in slave mode.

Multiple DVS-21 systems are combined into a group. Here one system
must be designated as master to which the others synchronize.

- Synchronize external clock (T3)

Example 2: Clock extraction from a DVS-21. One device is master, the others are in slave mode.

Two DVS-21 systems are combined together over e.g. a multiplexer (e.g.
XMP1) over a transmitting network. The devices synchronize to the
external clock T3.

Date:

19.03.2009 Page:

4/7 Author:

Document-No.:

DB_E1_ 2861_01