PEB22554 SIEMENS [Siemens Semiconductor Group], PEB22554 Datasheet - Page 315

• Manufacturer Part Number: PEB22554
• Description: ICs for Communications
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

Pulse Count Recovery (Read/Write)
Value after RESET: 00
PCR
PCR7…PCR0… Pulse Count Recovery
Line Interface Mode 2 (Read/Write)
Value after RESET: 00
LIM2
LBO2...LBO1… Line Build-Out
Semiconductor Group
7
7
PCR7
LBO2
A LOS alarm (red alarm) will be cleared if a pulse density is detected
in the received bit stream.The number of pulses M which must occur
in the predefined PCD time interval is programmable via the PCR
register and can be calculated as follows:
M = N+1 ; with 0 =< N =< 255.
The time interval starts with the first detected pulse transition. With
every received pulse a counter will be incremented and the actual
counter is compared with the contents of PCR register. If the pulse
number >= the PCR value the LOS alarm will be reset otherwise the
alarm will still be active. In this case the next detected pulse transition
will start a new time interval.
An additional Loss of Signal recovery condition may be selected by
register LIM2.LOS1.
In long haul applications LIM0.EQON = 1 a transmit filter can be
optionally placed on the transmit path to attenuate the data on pins
XL1/2. Selecting the transmitter attenuation is possible in steps of
7.5 dB @772kHz which is according to FCC 68 or ANSI T1. 403.
To meet the line build-out defined by ANSI T1.403 registers XPM2-0
should be programmed as follows:
00… 0 dB
01… -7.5 dB
10… -15 dB
LBO1
H
H
-->
-->
XPM2-0 = 20
XPM2-0 = 20
315
SCF
Operational Description T1 / J1
ELT
H
H
, 02
, 01
H
H
, 51
, 51
H
H
0
0
PCR0
LOS1
PEB 22554
(x39)
(x3A)
09.98