
XRT86SH328
PRELIMINARY
216
28-CHANNEL DS1/E1 FRAMER/LIU WITH DS3 MUX & VT-MAPPER - SONET APPLICATIONS
REV. P1.0.6
BIT 7 - Unused:
BIT 6 - One and Only:
This READ/WRITE bit-field is used to select the F-bit acquisition criteria that the M12 DeMUX block will use, whenever
it is operating in the F-Bit Search state, as described below.
`
0 - Configures the M12 De-MUX block to move onto the M-Bit Search state, whenever it has properly located 8 (or
16) consecutive F-bits (as configured in Bit 4 of this register).
`
1 - Configures the M12 De-MUX block to move onto the M-Bit Search state, whenever it has (1) properly located 8
(or 16) consecutive F-bits and (2) when it has located and identified only one viable F-Bit Alignment candidate.
N
OTE
:
If the user sets this bit-field to 1, then the M12 De-MUX block will NOT transition into the M-Bit Search state as
long as at least two viable candidate sets of bits appears to function as the F-bits.
BIT 5 - DS2 M-Sync:
This READ/WRITE bit-field is used to select the M-Bit Acquisition criteria whenever the M12 De-MUX block is operating
in the M-Bit Search state.
`
0 - Configures the M12 De-MUX block to declare the In-Frame state, when it has properly located 4 consecutive M-
bits (while detecting no F-bit errors).
`
1 - Configures the M12 De-MUX block to declare the In-Frame state, when it has properly located 8 consecutive M-
bits (while detecting no F-bit errors).
BIT 4 - DS2 F-Sync:
This READ/WRITE bit-field is used to select the F-Bit Acquisition criteria whenever the M12 De-MX block is operating
in the F-Bit Search state.
`
0 - Configures the M12 De-MUX block to move onto the M-Bit Search state, when it has properly located 8
consecutive F-bits.
`
1 - Configures the M12 De-MUX block to move onto the M-Bit Search state, when it has properly located 16
consecutive F-bits.
BIT 3 - DS2 LOF - F Bits/G.747 FAS Bit Error Count
The exact function of this bit-field depends upon whether the M12 MUX/De-MUX block has been configured to operate
in the DS2 or in the G.747 Mode, as described below.
If M12 MUX/M12 De-MUX # 1 is configured to operate in the DS2 Mode:
This READ/WRITE bit-field is used to select the F-Bit LOF (Loss of Frame) Defect criteria for the M12 De-MUX
associated with DS2 Channel 1.
`
0 - Configures the M12 De-MUX block to declare the DS2 LOF defect condition whenever the M12 De-MUX block
detects two (2) F-bit errors within the four (4) most recently received F-bits within the incoming DS2 data-stream.
`
1 - Configures the M12 De-MUX block to declare the DS2 LOF defect condition whenever the M12 De-MUX defect
two (2) F-bit errors within the five (5) most recently received F-bits within the incoming DS2 data-stream.
If M12 MUX/M12 De-MUX # 1 is configured to operate in the G.747 Mode:
This READ/WRITE bit-field is used to specify how the M12 De-MUX increments G.747 Framing Alignment Signal (FAS)
errors.
The user can configure the M12 De-MUX to increment the PMON DS2 # 1 Framing Bit Error Count Register on either
T
ABLE
289: DS3 F
RAMER
B
LOCK
- M12 DS2 # 1 F
RAMER
C
ONFIGURATION
R
EGISTER
(A
DDRESS
= 0
X
0E3A)
B
IT
7
B
IT
6
B
IT
5
B
IT
4
B
IT
3
B
IT
2
B
IT
1
B
IT
0
Unused
One and
Only
DS2 M-Sync
DS2 F-Sync
DS2 LOF
- F Bits/
G.747
FAS Bit
Error Count
DS2 LOF - M
Bits
DS2 LOF
- M Bits
Disable
DS2
Reframe
R/O
R/W
R/W
R/W
R/W
R/W
R/W
R/W
0
0
0
0
0
0
0
0