STANDARD PRODUCT
PM4328 TECT3
DATASHEET
PMC-2011596
ISSUE 1
HIGH DENSITY T1/E1 FRAMER
AND M13 MULTIPLEXER
Valid X-bits are extracted by the DS3-FRMR to provide indication of far end
receive failure (FERF). A FERF defect is detected if the extracted X-bits are
equal and are logic 0 (X1=X2=0); the defect is removed if the extracted X-bits are
equal and are logic 1 (X1=X2=1). If the X-bits are not equal, the FERF status
remains in its previous state. The extracted FERF status is buffered for 2 M-
frames before being reported within the DS3 FRMR Status register. This buffer
ensures a better than 99.99% chance of freezing the FERF status on a correct
value during the occurrence of an out of frame.
When the C-bit parity application is enabled, both the far end alarm and control
(FEAC) channel and the path maintenance data link are extracted. Codes in the
FEAC channel are detected by the Bit Oriented Code Detector (RBOC). HDLC
messages in the Path Maintenance Data Link are received by the Data Link
Receiver (RDLC).
The DS3-FRMR can be enabled to automatically assert the RAI indication in the
outgoing transmit stream upon detection of any combination of LOS, OOF or
RED, or AIS. The DS3-FRMR can also be enabled to automatically insert C-bit
Parity FEBE upon detection of receive C-bit parity error.
The DS3-FRMR may be configured to generate interrupts on error events or
status changes. All sources of interrupts can be masked or acknowledged via
internal registers. Internal registers are also used to configure the DS3-FRMR.
Access to these registers is via a generic microprocessor bus.
9.23 Performance Monitor Accumulator (DS3-PMON)
The Performance Monitor (PMON) Block interfaces directly with the DS3 Framer
(DS3-FRMR). Saturating counters are used to accumulate:
Sꢀ line code violation (LCV) events
Sꢀ parity error (PERR) events
Sꢀ path parity error (CPERR) events
Sꢀ far end block error (FEBE) events
Sꢀ excess zeros (EXZS)
Sꢀ framing bit error (FERR) events
Due to the off-line nature of the DS3 Framer, PMON continues to accumulate
performance meters even while the DS3-FRMR has declared OOF.
PROPRIETARY AND CONFIDENTIAL
80
PMC [ PMC-SIERRA, INC ]
