
XRT72L52
REV. 1.0.1
xr
TWO CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER
XII
R
X
E3 C
ONFIGURATION
& S
TATUS
R
EGISTER
- 2 (A
DDRESS
= 0
X
11).........................................................338
R
X
E3 I
NTERRUPT
E
NABLE
R
EGISTER
- 2 (A
DDRESS
= 0
X
13)....................................................................338
R
X
E3 I
NTERRUPT
S
TATUS
R
EGISTER
- 2 (A
DDRESS
= 0
X
15)....................................................................339
R
X
E3 I
NTERRUPT
E
NABLE
R
EGISTER
- 2 (A
DDRESS
= 0
X
13)....................................................................339
R
X
E3 I
NTERRUPT
S
TATUS
R
EGISTER
- 2 (A
DDRESS
= 0
X
15)....................................................................340
R
X
E3 LAPD C
ONTROL
R
EGISTER
(A
DDRESS
= 0
X
18)..............................................................................340
R
X
E3 LAPD C
ONTROL
R
EGISTER
(A
DDRESS
= 0
X
18)..............................................................................340
6.0 E3/ITU-T G.832 Operation of the XRT72L52 ....................................................................................342
F
RAMER
O
PERATING
M
ODE
R
EGISTER
(A
DDRESS
= 0
X
00) .......................................................................342
6.1 D
ESCRIPTION
OF
THE
E3, ITU-T G.832 F
RAMES
AND
A
SSOCIATED
O
VERHEAD
B
YTES
...................................... 342
Figure 142. Illustration of the E3, ITU-T G.832 Framing Format................................................................................... 342
6.1.1 Definition of the Overhead Bytes.......................................................................................................... 342
F
RAMER
O
PERATING
M
ODE
R
EGISTER
(A
DDRESS
= 0
X
00) .......................................................................343
T
ABLE
65: D
EFINITION
OF
THE
T
RAIL
T
RACE
B
UFFER
B
YTES
,
WITHIN
T
HE
E3, ITU-T G.832 F
RAMING
F
ORMAT
.................. 344
T
HE
M
AINTENANCE
AND
A
DAPTATION
(
MA
)
BYTE
FORMAT
..........................................................................344
T
ABLE
66: A L
ISTING
OF
THE
V
ARIOUS
P
AYLOAD
T
YPE
V
ALUES
AND
THEIR
CORRESPONDING
M
EANING
.............................. 345
6.2 T
HE
T
RANSMIT
S
ECTION
OF
THE
XRT72L52 (E3 M
ODE
O
PERATION
) ................................................................ 345
Figure 143. The Transmit Section configured to operate in the E3 Mode..................................................................... 346
6.2.1 The Transmit Payload Data Input Interface Block................................................................................ 346
Figure 144. The Transmit Payload Data Input Interface Block ..................................................................................... 347
T
ABLE
67: L
ISTING
AND
D
ESCRIPTION
OF
THE
PINS
ASSOCIATED
WITH
THE
T
RANSMIT
P
AYLOAD
D
ATA
I
NPUT
I
NTERFACE
.... 348
Figure 145. The Terminal Equipment being interfaced to the Transmit Payload Data Input Interface block for Mode 1(Serial/
Loop-Timed) Operation.................................................................................................................................. 350
Figure 146. Behavior of the Terminal Interface signals between the Transmit Payload Data Input Interface block of the
XRT72L52 and the Terminal Equipment (for Mode 1 Operation) .................................................................. 351
F
RAMER
O
PERATING
M
ODE
R
EGISTER
(A
DDRESS
= 0
X
00) .......................................................................351
Figure 147. The Terminal Equipment being interfaced to the Transmit Payload Data Input Interface block for Mode 2 (Serial/
Local-Timed/Frame-Slave) Operation ........................................................................................................... 352
Figure 148. Behavior of the Terminal Interface signals between the XRT72L52 and the Terminal Equipment (Mode 2
Operation)...................................................................................................................................................... 353
F
RAMER
O
PERATING
M
ODE
R
EGISTER
(A
DDRESS
= 0
X
00) .......................................................................353
Figure 149. The Terminal Equipment being interfaced to the Transmit Payload Data Input Interface block for Mode 3 (Serial/
Local-Timed/Frame-Master) Operation ......................................................................................................... 354
Figure 150. Behavior of the Terminal Interface signals between the XRT72L52 and the Terminal Equipment (E3 Mode 3
Operation)...................................................................................................................................................... 355
RAMER
O
PERATING
M
ODE
R
EGISTER
(A
DDRESS
= 0
X
00) .......................................................................356
Figure 151. The Terminal Equipment being interfaced to the Transmit Payload Data Input Interface block for Mode 4 (Nibble-
Parallel/Loop-Timed) Operation..................................................................................................................... 357
Figure 152. Behavior of the Terminal Interface signals between the XRT72L52 and the Terminal Equipment (Mode 4
Operation)...................................................................................................................................................... 358
F
RAMER
O
PERATING
M
ODE
R
EGISTER
(A
DDRESS
= 0
X
00) .......................................................................359
Figure 153. The Terminal Equipment being interfaced to the Transmit Payload Data Input Interface block for Mode 5 (Nibble-
Parallel/Local-Timed/Frame-Slave) Operation .............................................................................................. 360
Figure 154. Behavior of the Terminal Interface signals between the XRT72L52 and the Terminal Equipment (E3 Mode 5
Operation)...................................................................................................................................................... 361
F
RAMER
O
PERATING
M
ODE
R
EGISTER
(A
DDRESS
= 0
X
00) .......................................................................361
Figure 155. The Terminal Equipment being interfaced to the Transmit Payload Data Input Interface block for Mode 6 (Nibble-
Parallel/Local-Timed/Frame-Master) Operation ............................................................................................ 362
Figure 156. Behavior of the Terminal Interface signals between the XRT72L52 and the Terminal Equipment (E3 Mode 6
Operation)...................................................................................................................................................... 363
F
RAMER
O
PERATING
M
ODE
R
EGISTER
(A
DDRESS
= 0
X
00) .......................................................................363
6.2.2 The Transmit Overhead Data Input Interface....................................................................................... 363
Figure 157. The Transmit Overhead Data Input Interface block................................................................................... 364
T
ABLE
68: A L
ISTING
OF
THE
O
VERHEAD
BITS
WITHIN
THE
E3
FRAME
,
AND
THEIR
POTENTIAL
SOURCES
,
WITHIN
THE
XRT72L52 IC
365
T
ABLE
69: D
ESCRIPTION
OF
M
ETHOD
1 T
RANSMIT
O
VERHEAD
I
NPUT
I
NTERFACE
S
IGNALS
................................................. 367
Figure 158. The Terminal Equipment being interfaced to the Transmit Overhead Data Input Interface (Method 1)..... 368
T
ABLE
70: T
HE
R
ELATIONSHIP
BETWEEN
THE
N
UMBER
OF
R
ISING
C
LOCK
E
DGES
IN
T
X
OHC
LK
, (
SINCE
"T
X
OHF
RAME
"
WAS
LAST
SAMPLED
"H
IGH
")
TO
THE
E3 O
VERHEAD
B
IT
,
THAT
IS
BEING
PROCESSED
......................................................... 369
Figure 159. Illustration of the signal that must occur between the Terminal Equipment and the XRT72L52, in order to
configure the XRT72L52 to transmit a Yellow Alarm to the remote terminal equipment ............................... 371
T
ABLE
71: D
ESCRIPTION
OF
M
ETHOD
1 T
RANSMIT
O
VERHEAD
I
NPUT
I
NTERFACE
S
IGNALS
................................................. 373