PEB24911HV13TR Lantiq, PEB24911HV13TR Datasheet - Page 100

• Manufacturer Part Number: PEB24911HV13TR
• Manufacturer: Lantiq

Specifications of PEB24911HV13TR

• Lead Free Status / Rohs Status: Supplier Unconfirmed

<––––– C/I AR
4.4.1.2
For loopback #2 several alternatives exist. Both the type of loopback and the location
may vary. Three loopback types belong to the loopback #2 category:
• Complete loopback, in the NT U-transceiver or in a downstream device
• B1-channel loopback, always performed in the NT U-transceiver
• B2-channel loopback, always performed in the NT U-transceiver
All loop variations are closed as near to the IOM
Complete Loopback
The complete loopback comprises both B-channels and the D-channel. It may be closed
either in the U-transceiver itself or in a downstream device. The propagation delay of B
and D-channel data is identical.
Single Channel Loopback
Single channel loopbacks are always performed within the U-transceiver. In this case the
digital data of DOUT will be directly fed back into DIN. This also applies if the complete
loopback is closed in the U-transceiver.
Normally loopback #2 is controlled from the exchange by the MON-0 commands LBBD,
LB1 and LB2. The loop requests are recognized and executed automatically by the NT
U-transceiver if automode is selected.
All loopback functions are latched in the NT. This allows channel B1 and channel B2 to
be looped back simultaneously. All loopbacks are opened again upon reception of the
EOC command RTN.
Transparency
Data sent downstream will be passed on transparent independently of closed loopbacks.
Data Sheet
NT IOM
Loopback No.2 - Overview
®
-2
(1000B) C/I AR
LT IOM
C/I ARM
C/I UAI
C/I RES
®
-2
(1000B) –––––> ; Activation proceeds in
(1001B) –––––> ; and LT
(0111B) –––––> ;
(0001B) <––––– ;
90
®
-interface as possible.
;
;
NT
Activation complete,
#1 closed
Open loopback #1,
reset the U-transceiver
Operational Description
PEF 24911
2001-07-16