PEF2091 Siemens Semiconductor Group, PEF2091 Datasheet - Page 120

• Manufacturer Part Number: PEF2091
• Description: ICs for Communications(ISDN Echocancellation Circuit)
• Manufacturer: Siemens Semiconductor Group

Semiconductor Group
SB Transmission in Repeater Modes
Note 36: This section applies to NT-RP and NT-RP modes (see "Basic Operating
In these modes all of the Single Bits need to be controlled via MON-2-messages. This
permits to implement national repeater specifications for overhead bit treatment. For a
short explanation of the function of the SB in both NT and LT modes refer to Tables 22
and 24 above.
4.2.3.2
The received Single Bits from the U-interface are forwarded via MON-2 messages to the
controller unit
Figure 52
The IEC-Q Version 5.3 allows almost free control of the conditions for Single Bits
verification. Single Bits can be filtered and forwarded in one of the following ways:
• A MON-2 is issued if the polarity of at least one of the Single Bits, other than FEBE,
• A MON-2 message will be issued only if in addition no CRC violations have been
• Furthermore, verification of Single Bits changes can be chosen to be controlled by a
1) Upstream in the LT modes and downstream in the NT modes
has been changed. (Compatible to Version 5.1).
detected in the completed last two superframes. (Compatible to all previous IEC-Q
versions other than Version 5.1).
triple last look processor. Choosing this filtering method will imply that a change in a
Single Bit will be issued via MON-2 message only if an identical bit value has been
received for three consecutive superframes.
Time
Mode", page 50).
Single Bits Reception from U
1)
Access to Single Bits Received from U
to allow higher layer evaluation of these data.
M5-M6
2 Bit
1 Bit
M4
U Basic Frame
1.5 ms
M1-M3
3 Bits
120
12x (2B+D)
216 Bits
Data
Processor
18 Bits
Fixed
(I)SW
SB
Operational Description
MON-1, -2
To IOM
µP (if used)
Receiver
(From U)
Data Sheet 01.99
®
Data
-2 and
PEB 2091
PEF 2091