PEF2091 Siemens Semiconductor Group, PEF2091 Datasheet - Page 239

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

6.7.3
The typical procedure for closing and opening a single channel loop-back is
demonstrated in the examples below.
Single-Channel Loop-Back in EOC Auto Mode
–––––> C/I AI
<––––– C/I AI
<––––– MON-0 LB1 (51
<––––– MON-0 LB2 (52
<––––– MON-0
In the above example the LT is operated in EOC Auto mode.
Semiconductor Group
NT
RTN
Examples for Single Channel Loop-Back #2 Control
(1100
(1100
(FF
H
H
H
)
)
)
B
B
) C/I AR
) C/I AI
LT
MON-0 LB1 (51
MON-0 LB1
MON-0 LB2 (52
MON-0 LB2
MON-0 RTN (FF
MON-0 RTN (FF
239
(1000
(1100
(52
(51
H
H
H
H
H
H
)
)
)
)
)
)
B
B
)
)
<––––– ; U-interface is activated
–––––>
<––––– ; Close B1 loop (EOC)
–––––> ; Receive acknowledgment
<––––– ; Close B2 loop-back (EOC)
–––––> ; Receive acknowledgment
<––––– ; Open all loop-backs
–––––> ; Receive acknowledgment
; Loop B1 closed
;
;
; All loop-backs opened
Loop-back B1 and B2
closed
Data Sheet 01.99
Programming
PEB 2091
PEF 2091