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12.5.2 Receive Side Line Encoder/Decoder Register Map
The receive side utilizes six registers.
Table 12-16. Receive Side B3ZS/HDB3 Line Encoder/Decoder Register Map
Address
(0,2,4,6)90h LINE.RCR
(0,2,4,6)92h
(0,2,4,6)94h LINE.RSR
(0,2,4,6)96h LINE.RSRL
(0,2,4,6)98h LINE.RSRIE
(0,2,4,6)9Ah
(0,2,4,6)9Ch LINE.RBPVCR
(0,2,4,6)9Eh LINE.REXZCR
Register
Register Description
Line Receive Control Register
Unused
Line Receive Status Register
Line Receive Status Register Latched
Line Receive Status Register Interrupt Enable
Unused
Line Receive Bipolar Violation Count Register
Line Receive Excessive Zero Count Register
--
--
12.5.2.1 Register Bit Descriptions
Register Name:
Register Description:
Register Address:
Bit #
Name
Default
Bit #
Name
Default
Bit 2: E3 Code Violation Enable (E3CVE)
– When 0, the bipolar violation count will be a count of bipolar
violations. When 1, the bipolar violation count will be a count of E3 line coding violations. Note: E3 line coding
violations are defined as consecutive bipolar violations of the same polarity in ITU O.161. This bit is ignored in
B3ZS mode.
LINE.RCR
Line Receive Control Register
(0.2.4.6)90h
15
--
0
14
--
0
13
--
0
12
--
0
11
--
0
10
--
0
9
--
0
8
--
0
7
--
0
6
--
0
5
--
0
4
--
0
3
2
1
0
E3CVE
0
REZSF
0
RDZSF
0
RZSD
0
Bit 2: Receive BPV Error Detection Zero Suppression Code Format (REZSF)
– When 0, BPV error detection
detects a B3ZS signature if a zero is followed by a bipolar violation (BPV), and an HDB3 signature if two zeros are
followed by a BPV. When 1, BPV error detection detects a B3ZS signature if a zero is followed by a BPV that has
the opposite polarity of the BPV in the previous B3ZS signature, and an HDB3 signature if two zeros are followed
by a BPV that has the opposite polarity of the BPV in the previous HDB3 signature. Note: Immediately after a reset,
this bit is ignored. The first B3ZS signature is defined as a zero followed by a BPV, and the first HDB3 signature is
defined as two zeros followed by a BPV. All subsequent B3ZS/HDB3 signatures will be determined by the setting of
this bit.
Note: The default setting (REZSF = 0) conforms to ITU O.162. The default setting may falsely decode actual BPVs
that are not codewords. It is recommended that REZSF be set to one for most applications. This setting is more
robust to accurately detect codewords.
Bit 1: Receive Zero Suppression Decoding Zero Suppression Code Format (RDZSF)
– When 0, zero
suppression decoding detects a B3ZS signature if a zero is followed by a bipolar violation (BPV), and an HDB3
signature if two zeros are followed by a BPV. When 1, zero suppression decoding detects a B3ZS signature if a
zero is followed by a BPV that has the opposite polarity of the BPV in the previous B3ZS signature, and an HDB3
signature if two zeros are followed by a BPV that has the opposite polarity of the BPV in the previous HDB3
signature. Note: Immediately after a reset (
DRST
or
RST
low), this bit is ignored. The first B3ZS signature is defined