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PM7346 S/UNI-QJET
DATASHEET
PMC-960835
ISSUE 6
SATURN QUAD USER NETWORK INTERFACE FOR J2, E3, T3
PMC-SIERRA, INC. PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA INC., AND ITS CUSTOMERS’ INTERNAL USE
74
The T3-TRAN supports diagnostic modes in which it inserts parity or path parity
errors, F-bit framing errors, M-bit framing errors, invalid X or P-bits, line code
violations, or all-zeros.
User control of each of the overhead bits in the DS3 frame is provided.
Overhead bits may be inserted on a bit-by-bit basis from a user supplied data
stream. An overhead clock (at 526 kHz) and a DS3 overhead alignment output
are provided to allow for control of the user provided stream.
9.14 E3 Transmitter
The E3 Transmitter (E3-TRAN) Block integrates circuitry required to insert the
overhead bits into an E3 bit stream and produce an HDB3-encoded signal. The
E3-TRAN is directly compatible with the G.751 and G.832 framing formats.
The E3-TRAN generates the frame alignment signal and inserts it into the
incoming serial stream based on either the G.751 or G.832 formats and an
alignment pulse applied to it by the SPLT block. All overhead and status bits in
each frame format can be individually controlled by register bits or by the
transmit overhead stream. While in certain framing format modes, the E3-TRAN
generates various overhead bytes according to the following:
In G.832 E3 format, the E3-TRAN:
inserts the BIP-8 byte calculated over the preceding frame;
inserts the Trail Trace bytes through the Trail Trace Buffer (TTB) block;
inserts the FERF bit via a register bit or, optionally, when the E3-FRMR
declares OOF, or when the loss of cell delineation (LCD) defect is declared;
inserts the FEBE bit, which is set to logic 1 when one or more BIP-8 errors
are detected by the receive framer. If there are no BIP-8 errors indicated by
the E3-FRMR, the E3-TRAN sets the FEBE bit to logic 0;
inserts the Payload Type bits based on the register value set by the
microprocessor;
inserts the Tributary Unit multiframe indicator bits either via the TOH overhead
stream or by register bit values set by the microprocessor;
inserts the Timing Marker bit via a register bit;