PEB22554 SIEMENS [Siemens Semiconductor Group], PEB22554 Datasheet - Page 259

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

Alarm
RRA detection operates in the presence of 10exp(-3) bit error rate.
Semiconductor Group
Yellow Alarm or
Remote Alarm
(RRA)
Excessive Zeros
(EXZD)
Pulse Density
Violation
(PDEN)
Transmit Line
Short
(XLS)
Transmit Ones
Density
(XLO)
– Auto modes
- Automatic remote alarm (Yellow Alarm) access
If the receiver has lost its synchronization (FRS0.LFA) a remote alarm (yellow
alarm) could be sent automatically, if enabled by bit FMR2.AXRA to the distant end.
In synchronous state the remote alarm bit will be removed.
- Automatic AIS to system interface
In asynchronous state the synchronizer enforces automatically an AIS to the
receive system interface. However, received data may be transparently switched
through if bit FMR2.DAIS is set.
- Automatic clock source switching
In Slave mode (LIM0.MAS = 0) the DCO-R will synchronize to the recovered route
Detection Condition
RC1.RRAM = 0:
bit 2 = 0 in 255 consecutive
time-slots or
FS bit = 1 of frame12 in F12 (D4)
format or
8x1,8x0 in the DL channel (ESF )
RC1.RRAM = 1:
bit 2 = 0 in every time-slot per
frame or
FS bit = 1 of frame12 in F12 (D4)
format or
8x1,8x0 in the DL channel (ESF )
more than 7 (B8ZS code) or
more than 15 (AMI code)
contiguous zeros
less than 23 ones received in a
floating time window of 192 bits
or
more than 14 consecutive zeros
more than 32 pulse periods with
highly increased transmit line
current on XL1/2
32 consecutive zeros in the
transmit data stream on XL1/2
259
Clear Condition
RC1.RRAM = 0:
set conditions no longer
detected.
RC1.RRAM = 1:
bit 2 = 0 not detected in 3
consecutive frames or
FS bit not detected in 3
consecutive mulitframes or
8x1,8x0 not detected for 3 times
in a row (ESF).
Latched Status: cleared on read
Latched Status: cleared on read
no transmit line current limiter
active
Cleared with each transmitted
pulse
Functional Description T1 / J1
PEB 22554
09.98