XRT72L50
SINGLE CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER
REV. P1.1.3
á
PRELIMINARY
VIII
R
EGISTER
AND
THE
T
X
L
INE
C
LK
CLOCK
EDGE
THAT
T
X
POS
AND
T
X
NEG
ARE
UPDATED
ON
..................... 192
Figure 75. Illustration on how the Receive DS3 Framer (within the XRT72L50 Framer IC) being interfaced
to theXRT73L00 LIU, while the Framer is operating in Bipolar Mode (one channel shown) ............... 192
Figure 76. Illustration of AMI Line Code ............................................................................................. 193
Figure 77. Illustration of two examples of B3ZS Decoding ................................................................. 194
II/O C
ONTROL
R
EGISTER
(A
DDRESS
= 0
X
01) ......................................................................................... 194
T
ABLE
36: T
HE
R
ELATIONSHIP
BETWEEN
THE
CONTENTS
OF
B
IT
1 (R
X
L
INE
C
LK
I
NV
)
OF
THE
I/O C
ONTROL
R
EG
-
ISTER
,
AND
THE
SAMPLING
EDGE
OF
THE
R
X
L
INE
C
LK
SIGNAL
................................................................... 194
Figure 78. Waveform/Timing Relationship between RxLineClk, RxPOS and RxNEG - When RxPOS and
RxNEG are to be sampled on the rising edge of RxLineClk ................................................................ 195
Figure 79. Waveform/Timing Relationship between RxLineClk, RxPOS and RxNEG - When RxPOS and
RxNEG are to be sampled on the falling edge of RxLineClk ............................................................... 195
4.3.2 The Receive DS3 Framer Block ............................................................................................................ 195
Figure 80. A Simple Illustration of the Receive DS3 Framer Block and the Associated Paths to the Other
Functional Blocks ................................................................................................................................ 196
Figure 81. The State Machine Diagram for the Receive DS3 Framer block's Frame Acquisition/Mainte-
nance Algorithm ................................................................................................................................... 197
R
X
DS3 C
ONFIGURATION
AND
S
TATUS
R
EGISTER
, (A
DDRESS
= 0
X
10) ................................................... 198
T
ABLE
37: T
HE
R
ELATIONSHIP
BETWEEN
THE
CONTENTS
OF
B
IT
2 (F
RAMING
ON
P
ARITY
)
WITHIN
THE
R
X
DS3
C
ONFIGURATION
AND
S
TATUS
R
EGISTER
,
AND
THE
RESULTING
F
RAMING
A
CQUISITION
C
RITERIA
.............. 198
R
X
DS3 C
ONFIGURATION
AND
S
TATUS
R
EGISTER
, (A
DDRESS
= 0
X
10) ................................................... 198
T
ABLE
38: T
HE
R
ELATIONSHIP
BETWEEN
THE
CONTENTS
OF
B
IT
1 (F-S
YNC
A
LGO
)
WITHIN
THE
R
X
DS3 C
ONFIG
-
URATION
AND
S
TATUS
R
EGISTER
,
AND
THE
RESULTING
F-
BIT
OOF D
ECLARATION
CRITERIA
USED
BY
THE
R
ECEIVE
DS3 F
RAMER
BLOCK
............................................................................................................................. 199
R
X
DS3 C
ONFIGURATION
AND
S
TATUS
R
EGISTER
, (A
DDRESS
= 0
X
10) ................................................... 199
T
ABLE
39: T
HE
R
ELATIONSHIP
BETWEEN
THE
CONTENTS
OF
B
IT
0 (M-S
YNC
A
LGO
)
WITHIN
THE
R
X
DS3 C
ONFIG
-
URATION
AND
S
TATUS
R
EGISTER
,
AND
THE
RESULTING
M-B
IT
OOF D
ECLARATION
C
RITERIA
USED
BY
THE
R
E
-
CEIVE
DS3 F
RAMER
BLOCK
.................................................................................................................... 199
R
X
DS3 C
ONFIGURATION
AND
S
TATUS
R
EGISTER
, (A
DDRESS
= 0
X
10) ................................................... 199
I/O C
ONTROL
R
EGISTER
(A
DDRESS
= 0
X
01) .......................................................................................... 200
PMON F
RAMING
B
IT
E
RROR
E
VENT
C
OUNT
R
EGISTER
- MSB (A
DDRESS
= 0
X
52) ................................. 200
PMON F
RAMING
B
IT
E
RROR
E
VENT
C
OUNT
R
EGISTER
- LSB (A
DDRESS
= 0
X
53) .................................. 200
R
X
DS3 C
ONFIGURATION
AND
S
TATUS
R
EGISTER
, (A
DDRESS
= 0
X
10) ................................................... 201
R
X
DS3 C
ONFIGURATION
AND
S
TATUS
R
EGISTER
, (A
DDRESS
= 0
X
10) ................................................... 201
R
X
DS3 C
ONFIGURATION
AND
S
TATUS
R
EGISTER
, (A
DDRESS
= 0
X
10) ................................................... 202
R
X
DS3 C
ONFIGURATION
AND
S
TATUS
R
EGISTER
, (A
DDRESS
= 0
X
10) ................................................... 202
R
X
DS3 C
ONFIGURATION
AND
S
TATUS
R
EGISTER
, (A
DDRESS
= 0
X
10) ................................................... 202
R
X
DS3 S
TATUS
R
EGISTER
(A
DDRESS
= 0
X
11) ..................................................................................... 203
R
X
DS3 I
NTERRUPT
S
TATUS
R
EGISTER
(A
DDRESS
= 0
X
13) .................................................................... 203
R
X
DS3 S
TATUS
R
EGISTER
(A
DDRESS
= 0
X
11) ...................................................................................... 204
R
X
DS3 I
NTERRUPT
S
TATUS
R
EGISTER
(A
DDRESS
= 0
X
13) ..................................................................... 204
PMON P
ARITY
E
RROR
E
VENT
C
OUNT
R
EGISTER
- MSB (A
DDRESS
= 0
X
54) .......................................... 204
PMON P
ARITY
E
RROR
E
VENT
C
OUNT
R
EGISTER
- LSB (A
DDRESS
= 0
X
55) ........................................... 204
Figure 82. A Simple Illustration of the Locations of the Source, Mid-Network and Sink Terminal Equipment
(for CP-Bit Processing) ........................................................................................................................ 205
Figure 83. Illustration of the Presumed Configuration of the Mid-Network Terminal Equipment ........ 206
4.3.3 The Receive HDLC Controller Block ..................................................................................................... 207
R
X
DS3 FEAC I
NTERRUPT
E
NABLE
/S
TATUS
R
EGISTER
(A
DDRESS
= 0
X
17) ............................................ 208
R
X
DS3 FEAC R
EGISTER
(A
DDRESS
= 0
X
16) ....................................................................................... 208
R
X
DS3 FEAC I
NTERRUPT
E
NABLE
/S
TATUS
R
EGISTER
(A
DDRESS
= 0
X
17) ............................................ 208
Figure 84. Flow Diagram depicting how the Receive FEAC Processor Functions ............................. 209
Figure 85. LAPD Message Frame Format .......................................................................................... 210
R
X
DS3 LAPD C
ONTROL
R
EGISTER
(A
DDRESS
= 0
X
18) ........................................................................ 210
R
X
DS3 LAPD S
TATUS
R
EGISTER
(A
DDRESS
= 0
X
19) ........................................................................... 210
T
ABLE
40: T
HE
R
ELATIONSHIP
BETWEEN
R
X
LAPDT
YPE
[1:0]
AND
THE
RESULTING
LAPD M
ESSAGE
TYPE
AND