PEF2091 Siemens Semiconductor Group, PEF2091 Datasheet - Page 115

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

4.2.3
The transmission procedure of the Single Bits (SB) on the U-interface is mode
dependent. The reception procedure of the SB from the U-interface is independent
the mode used. Transmission and reception of SB will therefore be discussed in to
different sections below. For definition of Single Bits, see "Single Bits Channel", page 69.
For more information on Monitor Channel handling, see "IOM
page 76, and for the microprocessor mode "Monitor Channel Access", page 101.
Correspondence between MON-2 Messages and SB
The content of the MON-2 message (Table 20) corresponds to the Single Bits in the
U-frame (see "U-Frame Structure", page 68). Bit M46 in the MON-2 message, for
example, will be inserted at position M46 in the U-frame.
Table 20
4.2.3.1
Figure 51 sketches roughly how transmitted Single Bits can be accessed.
Figure 51
The Single Bits defined by a MON-2 message are latched. I.e. they need to be issued
only once. Repetition will be performed by the SB processor. If no MON-2 messages are
1) Exception: The default setting of the repeater modes for SB indication is different than the default setting in
Semiconductor Group
other modes, see "Single Bits Reception from U", page 120
MON-2
0 0 1 0
Transmitter
MON-1
From IOM
Pins PS1 and PS2
(To U)
Data
Access to the Single Bits of U-Interface
Single Bits Transmission on U
Content of MON-2 Message
Access to Single Bits Transmission on U
1) Applies only in NT modes
1)
, MON-2, MON-8
1. Byte
®
-2 or µP
M41 M51 M61 M42
1)
Overhead Bits
18 Bits
Fixed
(I)SW
12x (2B+D)
Processor
216 Bits
Data
SB
115
U Basic Frame
1.5 ms
M1-M3
3 Bits
M52 M62 M43 M44 M45 M46 M47 M48
1 Bit
M4
Operational Description
Overhead Bits
2. Byte
M5-M6
2 Bits
®
-2 Monitor Channel",
Data Sheet 01.99
Time
PEB 2091
PEF 2091
1)
of