PEF2091 Siemens Semiconductor Group, PEF2091 Datasheet - Page 247

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

6.8.10
In order to recognize a terminal initiated activation successfully the NT-RP must be in
"Power Up" condition to provide clocks for the LT-RP. During the activation procedure
the LT-RP-signal "UAI" needs to be changed into "AI" by the control unit.
LT-RP
C/I DC
C/I DI
C/I AR
C/I AR
C/I ARM
C/I UAI
C/I AI
6.8.11
The start of a deactivation procedure is passed from the LT to the NT side via Single bits
in the U-frame. These are interpreted by the LT-RP. Thereafter the deactivation process
in LT-RP and NT-RP is running mostly independent of each other as illustrated below.
No C/I-codes need to be converted by the control unit.
LT-RP
C/I AR
C/I AI
C/I DR
C/I DEAC
C/I DI
C/I DC
Semiconductor Group
Activation Initiated by TE with Repeater
Deactivation by Repeater
(1111
(1111
(1000
(1000
(1001
(0111
(1100
(1000
(1100
(0000
(0001
(1111
(1111
B
B
B
B
B
B
B
B
B
B
B
B
B
)
)
)
)
)
)
)
)
)
)
)
)
)
<––––– <––––– C/I PU
–––––> –––––> C/I TIM
–––––> –––––> C/I AR
<––––– <––––– C/I AR
–––––>
–––––> –––––> C/I AI
–––––> <––––– C/I AI
<––––– <––––– C/I AI
–––––> –––––> C/I AI
<––––– <––––– C/I AR
–––––> <––––– C/I DR
–––––> –––––> C/I DI
<––––– <––––– C/I DC
–––––> C/I TIM
<––––– C/I PU
NT-RP
NT-RP
247
(0111
(0000
(1000
(1000
(1100
(1100
(1100
(1100
(1000
(0000
(1111
(1111
(0111
(0000
B
B
B
B
B
B
B
B
B
B
B
B
B
B
) ; Initial state "Power Up" to
)
) ; Terminal requests activation
) ; Activation proceeds
)
) ; Activation complete
) ; Layer 1 is activated
)
) ; Deactivation started by LT
) ; Deactivation proceeds
)
) ; Deactivation complete
) ; Stay in "Power Up" to keep
) ; turned on.
provide timing
clocks
Data Sheet 01.99
Programming
PEB 2091
PEF 2091