
XRT86SH328
PRELIMINARY
298
28-CHANNEL DS1/E1 FRAMER/LIU WITH DS3 MUX & VT-MAPPER - SONET APPLICATIONS
REV. P1.0.6
BIT7 - Transmit Auxiliary Pattern:
This bit is used to transmit an auxiliary pattern (repeating …010101) to the transmit line interface.
`
0 = Disabled
`
1 = Enable AUXP Pattern
BIT6 - Loss of Frame Declaration Criteria
This bit is used to select Loss of Frame Declaration Criteria for the receive E1 framer block.
`
0 = Loss of frame is declared immediately if either CRC multi frame alignment or FAS alignment is lost.
`
1 = Loss of frame is declared immediately if FAS alignment is lost. If CRC multi frame alignment is lost for more than
8 msec, the E1 receive framer will force a frame search.
BIT [5:4] - Yellow Alarm and Multi Yellow Alarm Generation [1:0]:
These bits activate or deactivate the transmission of yellow and multi frame yellow alarm. The yellow alarm and multi
frame yellow alarm can be forced to transmit as 1, or be inserted upon detection of loss of alignment.
BIT [3:2] - Transmit AIS Pattern Select[1:0]
These two READ/WRITE bit-fields are used to select the type of AIS Pattern that the Transmit E1 Framer block will send
if enabled.
T
ABLE
435: E1 F
RAMER
B
LOCK
- A
LARM
G
ENERATION
R
EGISTER
(A
DDRESS
= 0
X
N108,
WHERE
N
RANGES
IN
VALUE
FROM
0
X
01
TO
0
X
38)
BIT7
BIT6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Transmi-
tAUXP Pat-
tern
LOF Decla-
rationCriteria
Transmit YEL and Multi
YEL[1:0]
Transmit AIS Pattern
Select[1:0]
AIS Defect Declaration Cri-
teria[1:0]
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
0
0
0
0
0
0
0
0
YEL and Multi YE
YEL
AND
M
ULTI
YEL[1:0]
Y
ELLOW
A
LARM
T
RANSMITTED
00 / 10
Disabled.
01
Automatic Transmission of YEL and CAS Multi YELWhenever the receive E1
framer block declares LOF or Loss CAS Multi Frame Alignment, the corresponding
transmit E1 framer block will automatically transmit the Yellow Alarm indicator by
setting BIT 3 of time slot 0 within the non-FAS frames to 1.
11
Force Transmission of YEL and CAS Multi YELBoth Yellow and Multi Frame Yel-
low Alarm are transmitted as '1'
The Relationship between Transmit AIS Pattern Select[1:0] and the resulting behavior of the Transmit
E1 Framer block
T
RANSMIT
AIS P
ATTERN
S
ELECT
[1:0]
T
RANSMIT
E1 F
RAMER
B
LOCK
A
CTION
00
Transmits Normal TrafficTransmit E1 Framer block does not transmit the AIS indicator.
It will (instead) transmit normal traffic
01
Unframed All Ones PatternThe Transmit E1 Framer block will transmit an Unframed
All Ones Pattern (as an AIS pattern) for the duration that these bit-fields are set to [0,
1].