PM4341AT1XC
DATA SHEET
PMC-900602
ISSUE 7
T1 FRAMER/TRANSCEIVER
purpose triple serializer. Data is sourced from 3 banks of 24 8-bit registers, each
bank supporting a single serial output.
The TPSC interfaces directly to the XBAS TSB and provides serial streams for
signalling control, idle code data and PCM data control.
The registers are accessible from the µP interface in an indirect address mode.
The BUSY indication signal can be polled from an internal status register to
check for completion of the current operation.
8.19 Inband Loopback Code Generator (XIBC)
The Inband Loopback Code Generator function is provided by the XIBC block.
This block generates a stream of inband loopback codes (IBC) to be inserted into
a T1 data stream.The IBC stream consists of continuous repetitions of a specific
code and can be either framed or unframed. When the XIBC is enabled to
generate framed IBC, the framing bit overwrites the inband code pattern.The
contents of the code and its length are programmable from 3 to 8 bits.The XIBC
interfaces directly to the XBAS Basic Transmitter block.
8.20 Bit Oriented Code Generator (XBOC)
The Bit Oriented Code Generator function is provided by the XBOC block. This
block transmits 63 of the possible 64 bit oriented codes in the Facility Data Link
th
channel in ESF framing format, as defined in ANSI T1.403-1989.The 64 code
(111111) is similar to the HDLC Flag sequence and is used in the XBOC to
disable transmission of any bit oriented codes.
Bit oriented codes are transmitted on the Facility Data Link channel as a 16-bit
sequence consisting of 8 ones, a zero, 6 code bits, and a trailing zero
(111111110xxxxxx0) which is repeated as long as the code is not 111111. The
transmitted bit oriented codes have priority over any data transmitted on the FDL
except for ESF YELLOW Alarm.The code to be transmitted is programmed by
writing the code register.
8.21 HDLCTransmitter (XFDL)
The HDLC Transmitter function is provided by the XFDL block.This block is
designed to provide a serial data link for the XBAS Basic Transmitter block.The
XFDL is used under microprocessor or DMA control to transmit HDLC data
frames in the ESF Facility Data Link when the T1XC is enabled to use the
internal HDLC transmitter.The XFDL performs all of the data serialization, CRC
generation, zero-bit stuffing, as well as flag, idle, and abort sequence insertion.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
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PMC [ PMC-SIERRA, INC ]
