XRT84L38IB Exar Corporation, XRT84L38IB Datasheet - Page 355

• Manufacturer Part Number: XRT84L38IB
• Description: Network Controller & Processor ICs 8 Ch T1/E1 Framer
• Manufacturer: Exar Corporation

Specifications of XRT84L38IB

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

REV. 1.0.1
Framer blocks. Hence, the following description applies to all eight of these individual Transmit DS1 Framer
blocks.
The purpose of the DS1 Receive Framer block is:
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The following sections discuss functionalities of the DS1 Receive Framer block in details.
10.2
The XRT84L38 Octal T1/E1/J1 Framer supports the following DS1 framing formats:
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N
The user can set the Framing Format Select [2:0] bits of the Framing Select Register (FSR) to determine which
DS1 framing format should XRT84L38 be configured to operate.
The table below shows configurations of the Framing Format Select [2:0] bits of the Framing Select Register
(FSR).
FRAMING SELECT REGISTER (FSR) (INDIRECT ADDRESS = 0XN0H, 0X07H)
OTE
N
To identify frame boundary and establish framing alignment synchronization.
To decode user data, inputted from the Receive DS1 LIU Interface block to the Terminal Equipment.
To provide individual data control and signaling conditioning of each DS0 channel.
To support the receiving and extraction of HDLC messages, from the remote receiving terminal.
To detect error conditions and generate indications and interrupts to notify the user that the local receive
framer has received error frames from the remote terminal.
To receive and decode alarm condition indicators from the remote terminal.
Super-Frame format (SF), also referred to as D4 framing
Extended Super-Frame format (ESF)
Non-signaling format (N)
T1DM framing format
SLC®96 data link framing format, which use the Super-Frame (SF) framing structure
UMBER
B
2-0
: If the framer is configured to receive DS1 frames according to one particular framing format, the transmitting side of
IT
the framer is also configured to transmit DS1 frames according to the same framing format.
How to Configure the Framer to Receive Data in Various DS1 Framing Formats
T1 Framing Select
B
IT
N
AME
B
IT
R/W
T
YPE
These READ/WRITE bit-fields allow the user to select one of the five T1
framing formats supported by the framer. These framing formats include
ESF, SLC
N
OTE
: Changing of framing format will automatically force the framer to
perform re-synchronization.
®
96, SF, N and T1DM mode.
335
Framing
SLC®96
Format
T1DM
ESF
SF
N
B
IT
Bit 2
D
0
1
1
1
1
ESCRIPTION
Bit 1
OCTAL T1/E1/J1 FRAMER
X
0
0
1
1
Bit 0
X
0
1
0
1
XRT84L38