
PRELIMINARY
XRT86SH328
205
REV. P1.0.6
28-CHANNEL DS1/E1 FRAMER/LIU WITH DS3 MUX & VT-MAPPER - SONET APPLICATIONS
BIT7 - M12 Remote Loop-Back Mode - DS1 Channel 3
This READ/WRITE bit-field is used to configure DS1 Channel 3 to operate in the M12 Remote Loop-back Mode. If the
user configures DS1 Channel 3 to operate in the M12 Remote Loop-back Mode, then the Egress Direction DS1 Channel
3 signal (as it is de-multiplexed from the DS2 signal by the M12 De-MUX block) will be internally looped back into the
Ingress Direction (back towards the M12 MUX block).
`
0 - Configures DS1 Channel 3 to NOT operate in the M12 Remote Loop-back Mode (Normal Operation)
`
1 - Configures DS1 Channel 3 to operate in the M12 Remote Loop-back Mode.
Figure 16
presents an illustration of the Functional Block Diagram of the XRT86SH328, whenever it has been
configured to operate in the M12 Remote Loop-back Mode.
BIT6 - M12 Remote Loop-Back Mode - DS1 Channel 2
See description of BIT7.
BIT 5 - M12 Remote Loop-Back Mode - DS1 Channel 1
T
ABLE
272: DS3 F
RAMER
B
LOCK
- M12 L
OOP
-
BACK
R
EGISTER
- 1 (A
DDRESS
= 0
X
0E28)
BIT7
BIT6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
M12 Remote
Loop Back
Mode - DS1
Channel 3
M12 Remote
Loop-Back
Mode - DS1
Channel 2
M12 Remote
Loop-Back
Mode - DS1
Channel 1
M12 Remote
Loop-Back
Mode - DS1
Channel 0
M12 Loop-
Back
Request -
DS1
Channel 3
M12 Loop-
Back
Request -
DS1
Channel 2
M12 Loop-
Back
Request -
DS1
Channel 1
M12 Loop-
Back
Request -
DS1
Channel 0
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
0
0
0
0
0
0
0
0
F
IGURE
16. I
LLUSTRATION
OF
THE
F
UNCTIONAL
B
LOCK
D
IAGRAM
OF
THE
XRT86SH328,
WHENEVER
IT
HAS
BEEN
CONFIGURED
TO
OPERATE
IN
THE
M12 R
EMOTE
L
OOP
-
BACK
M
ODE
STS-1/
STS-3
Telecom
Bus
Interface
Transmit
STS-1/3
TOH
Processor
Block
Receive
STS-1/3
TOH
Processor
Block
Transmit
STS-1 POH
Processor
Block
Receive
STS-1 POH
Processor
Block
VT/TU
De-Mapper
Block
Receive
DS3
Framer
Block
Transmit
DS3
Framer
Block
M23
MUX
Block
M23
De-MUX
Block
Ingress
Direction
Receive
DS1/E1
Framer
Block
Egress
Direction
Receive
DS1/E1
Framer
Block
Ingress
Direction
Transmit
DS1/E1
Framer
Block
Egress
Direction
Transmit
DS1/E1
Framer
Block
Receive
DS1/E1
LIU
Block
Transmit
DS1/E1
LIU
Block
DS3/
STS-1
LIU
Interface
M12
MUX
Block
M12
De-MUX
Block
DS1/E1
Jitter
Atten
Block
DS1/E1 Channel 0
DS1/E1 Channel 0
DS2 Channel 0
From DS1/E1 Channels 1 - 27
From DS2 Channels 1 - 6
To DS2 Channels 1 - 6
To DS1/E1 Channels 1 - 3
To DS1/E1
Channels 1 - 27
VT/TU
Mapper
Block
DS2 Channel 0
M12 Remote
Loop-back
Path