STANDARD PRODUCT
PM4328 TECT3
DATASHEET
PMC-2011596
ISSUE 1
HIGH DENSITY T1/E1 FRAMER
AND M13 MULTIPLEXER
Signals, Far End Receive Failure and idle signal can be inserted using either
internal registers or can be configured for automatic insertion upon received
errors. When M23 operation is selected, the C-bit Parity ID bit (the first C-bit of
the first M sub-frame) is forced to toggle so that downstream equipment will not
confuse an M23-formatted stream with stuck-at-1 C-bits for C-bit Parity
application. Transmit timing is from an external reference or from the receive
direction clock.
The TECT3 also supports diagnostic options which allow it to insert, when
appropriate for the transmit framing format, parity or path parity errors, F-bit
framing errors, M-bit framing errors, invalid X or P-bits, line code violations,
all-zeros, AIS, Remote Alarm Indications, and Remote End Alarms. A Pseudo
Random Binary Sequence (PRBS) can be inserted into a DS3 payload and
checked in the receive DS3 payload for bit errors. A fixed 100100… pattern is
available for insertion directly into the B3ZS encoder for proper pulse mask
shape verification.
When configured in DS3 multiplexer mode, seven 6312 kbit/s data streams are
demultiplexed and multiplexed into and out of the DS3 signal. Bit stuffing and
rate adaptation is performed. The C-bits are set appropriately, with the option of
inserting DS2 loopback requests. Interrupts can be generated upon detection of
loopback requests in the received DS3. AIS may be inserted in the any of the
6312 kbit/s tributaries in both the multiplex and demultiplex directions. C-bit
parity is supported by sourcing a 6.3062723 MHz clock, which corresponds to a
stuffing ratio of 100%.
Framing to the demultiplexed 6312 kbit/s data streams supports DS2 (ANSI
TI.107) frame formats. The maximum average reframe time is 7ms for DS2. Far
end receive failure is detected and M-bit and F-bit errors are accumulated. The
DS2 framer is an off-line framer, indicating both OOF and COFA events. Error
events (FERF, MERR, FERR, PERR, RAI, framing word errors) are still indicated
while the DS2 framer is indicating OOF, based on the previous alignment.
Each of the seven 6312 kbit/s multiplexers may be independently configured to
multiplex and demultiplex four 1544 kbit/s DS1s into and out of a DS2 formatted
signal. Tributary frequency deviations are accommodated using internal FIFOs
and bit stuffing. The C-bits are set appropriately, with the option of inserting DS1
loopback requests. Interrupts can be generated upon detection of loopback
requests in the received DS2. AIS may be inserted in any of the low speed
tributaries in both multiplex and demultiplex directions.
When configured as a DS3 framer the unchannelized payload of the DS3 link is
available to an external device.
PROPRIETARY AND CONFIDENTIAL
23
PMC [ PMC-SIERRA, INC ]
