PEF2091 Siemens Semiconductor Group, PEF2091 Datasheet - Page 154

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

Semiconductor Group
Table 29
Timer
T1
T2
T3
T4
T5
T6
T7
T8
T9
T10
4.4.2.3
Signals and indications are issued on the IOM
(predefined U-signals).
C/I-Indications
AI
AR
DEAC
Output Signals and Indications in LT Modes
Activation Indication
This indication signals that "ACT" = 1 has been received and that timer T8
has elapsed. This indication is not issued in case AR0 is applied or an
analog loop-back is operated.
Activation Request
The AR-code signals that a wake-up signal has been received and that a
start-up procedure has commenced. Receiver synchronization has not yet
been achieved.
When already partially active (U only activation), AR indicates that the "SAI"
bit was set to (1), i.e. the S/T-interface has become active.
Deactivation
This indication is issued in response to a DR-code (Pend. Deactivation,
Tear Down) and in the "Test" state (unless PFOFF is active, i.e. PS1 = (1)).
Timers for LT State Machine
Duration
(ms)
15000
3
40
6000
1000
6000
40
24
40
40
Function
Supervisor for start-up
TL-transmission
Receiver reset
Re-transmission of TL
Supervisor SN0 detect
Supervisor EC converge
Supervisor SN2 detect
Hold time
Delay time for AI detection
Hold time
"DEA" = (0) transmission
154
®
-2-interface (C/I-codes) and U-interface
Operational Description
EC training
EC converge
Receiver reset
Pend.
State
Alerting
Reset for loop
Wait for TN
Awake
transparent
Awake error
Pend. Deactivation
Data Sheet 01.99
PEB 2091
PEF 2091