peb3456 Infineon Technologies Corporation, peb3456 Datasheet - Page 82

• Manufacturer Part Number: peb3456
• Description: Channelized T3 Termination With Ds3 Framer, M13 Multiplexer, T1/ E1 Framers And 256 Channel Hdlc/ppp Controller
• Manufacturer: Infineon Technologies Corporation

the pattern ‘1111 1111 0000 0000’ in the Data Link (DL).
Detection
Remote Alarm (yellow alarm) is detected and flagged with bit FRS.RRA when the pattern
’1111 1111 0000 0000’ is received in the DL bits if RFMR.SRAF=0. If RFMR.SRAF=1,
yellow alarm is detected when every bit2 of each time slot is 0. If RFMR.RRAM is set,
Remote Alarm can be detected even in the presence of BER 1/1000. FRS.RRA will be
reset automatically when the alarm condition is no longer detected.
4.6.2.4
The Facility Data Link (FDL) contains bit oriented messages (priority or command/
response) or HDLC-based message oriented signals that are processed by a HDLC
machine. Each T1 port has its dedicated FDL controller. In HDLC mode CRC16 is
supported. Additionally one or two byte address comparison is supported.
Note: CAS - BR (Channel Associated Signalling - bit robbing) is not supported. The
multiplication by x6 and then division (modulo 2) by the generator polynomial x6+x+1 of
the polynomial corresponding to multiframe N. The first check bit c1 is the most
significant bit of the remainder; the last check bit c6 is the least significant bit of the
remainder.
Check
At the receiver, the received multiframe, with each F-bit having first been replaced by a
binary 1, is acted upon by the multiplication/division process described above. The
resulting remainder is compared on a bit-by-bit basis, with the CRC-6 check bits
contained in the subsequently received multiframe.
In synchronous state a received CRC-6 error may generate an interrupt status and will
increment a CRC-6 counter.
4.6.2.3
Generation
If TFMR.AXRA=1, the remote alarm sequence will be automatically sent in the outgoing
data stream when the receiver is in asynchronous state (FRS.LFA bit is set). Remote
Alarm is also sent unconditionally when TCMDR.XRA=’1’. ESF RA is sent by repeating
Data Sheet
protocol machines support access to 56 kBit/s or 64 kBit/s data channels with their
bit masking function. If CCS (Common Channel Signalling) is used, the
corresponding channel (usually time slot 24) is handled as a standard data time
slot by the HDLC/PPP machine and the data is transferred via the PCI bus.
Remote Alarm (Yellow Alarm) Generation / Detection
Facility Data Link
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Functional Description
PEB 3456 E
05.2001