DS32506NW Maxim Integrated, DS32506NW Datasheet - Page 32

• Manufacturer Part Number: DS32506NW
• Description: Network Controller & Processor ICs
• Manufacturer: Maxim Integrated

Specifications of DS32506NW

• Part # Aliases: 90-32506-NW0

The DLOS detector supports the requirements of ANSI T1.231 for STS-1 LOS defects. At the STS-1 rate, the time
required for the DLOS detector to count 192 consecutive zeros falls in the range of 2.3 ≤ T ≤ 100 μ s required by
ANSI T1.231 for declaring an LOS defect. Although the time required for the DLOS detector to count 192
consecutive pulse intervals with no excessive zeros is less than the 125 μ s to 250 μ s period required by ANSI
T1.231 for clearing an LOS defect, a period of this length where LOS is inactive can easily be timed in software.
During LOS, the
constant than the DLOS detector. Thus, when the incoming signal is lost, the DLOS detector activates first
(asserting the
detector does not get a valid signal that it can qualify for no EXZ occurrences until the ALOS detector has seen the
signal rise above a signal level approximately 22dB below nominal.
8.3.6 Framer Interface Format and the B3ZS/HDB3 Decoder
The recovered data can be output in either bipolar or binary format. Reception of a B3ZS or HDB3 codeword is
flagged by the LINE.RSRL:ZSCDL latched status bit.
8.3.6.1
To select the bipolar interface format, pull the
bipolar format, the B3ZS/HDB3 decoder is disabled and the recovered data is buffered and output on the
and
are indicated by
In DS3 and STS-1 modes an excessive zeros error (EXZ) is declared whenever there is an occurrence of 3 or
more zeros in a row in the receive data stream. In E3 mode, an EXZ error is declared whenever there is an
occurrence of 4 or more zeros. EXZs are flagged by the LINE.RSRL:EXZL and EXZCL latched status bits and
accumulated in the
In all three modes (DS3, E3, and STS-1) a bipolar violation is declared if two positive pulses are received without
an intervening negative pulse or if two negative pulses are received without an intervening positive pulse. Bipolar
violations (BPVs) are flagged by the LINE.RSRL:BPVL and BPVCL latched status bits and accumulated in the
LINE.RBPVCR
8.3.6.2
To select the binary interface format, pull the
(per port). In binary format, the B3ZS/HBD3 decoder is enabled, and the recovered data is decoded and output as
a binary (NRZ) value on the
detected and flagged on the
In DS3 and STS-1 modes, B3ZS decoding is performed. In these modes, whenever a B3ZS codeword is found in
the receive data stream it is replaced with three zeros. In E3 mode HDB3 decoding is performed. In this mode,
whenever an HDB3 codeword is found in the receive data stream it is replaced with four zeros. The decoding
search criteria for a B3ZS/HDB3 codeword is programmable using the LINE.RCR:RDZSF control bit.
An excessive zeros error (EXZ) is declared in DS3 and STS-1 modes whenever there is an occurrence of 3 or
more zeros in a row in the receive data stream. In E3 mode, an EXZ error is declared whenever there is an
occurrence of 4 or more zeros in a row. EXZs are flagged by the LINE.RSRL:EXZL and EXZCL latched status bits
and accumulated in the
A bipolar violation error (BPV error) is declared in DS3 and STS-1 modes if a BPV is detected that is not part of a
valid B3ZS codeword. In E3 mode, a bipolar violation error is declared whenever a BPV is detected that is not part
of a valid HDB3 codeword. In E3 mode if LINE.RCR:E3CVE = 1, code violations are detected rather than bipolar
violation errors. A code violation is declared whenever consecutive BPVs (not BPV errors) have the same polarity
(ITU O.161 definition). The error detection search criteria for a B3ZS/HDB3 codeword is programmable using the
LINE.RCR:REZSF control bit. Bipolar violations (or code violations if LINE.RCR:E3CVE = 1) are flagged by the
LINE.RSRL:BPVL and BPVCL latched status bits and accumulated in the
In the discussion that follows, a valid pulse that conforms to the AMI rule is denoted as B. A BPV pulse that violates
the AMI rule is denoted as V.
In DS3 and STS-1 modes, B3ZS decoding is performed, and
data
RNEG
RDAT
Bipolar Interface Format
Binary Interface Format
outputs for subsequent decoding by a downstream framer or mapper. Received positive-polarity pulses
causes ones of the following code violations:
RLOS
register.
RPOS
RCLK
LINE.REXZCR
pin and LOS status bit), followed by the ALOS detector. When a signal is restored, the DLOS
= 1, while negative-polarity pulses are indicated by
output pin is derived from the LIU’s reference clock. The ALOS detector has a longer time
LINE.REXZCR
RLCV
RDAT
register.
pin.
pin, while bipolar violations, code violations, and excessive zero errors are
register.
RBIN
RBIN
pin high (all ports) or set the PORT.CR2:RBIN configuration bit
32 of 130
pin low and clear the PORT.CR2:RBIN configuration bit. In
RLCV
is asserted during any
LINE.RBPVCR
RNEG
= 1.
DS32506/DS32508/DS32512
register.
RCLK
cycle where the
RPOS