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PRELIMINARY
DS3 UNI FOR ATM
XRT7245
REV. 1.03
201
Register (Address = 16h). The bit format of this register
is presented below.
The role/function of each of these bit-fields within the
register, are discussed below.
6.4.4.2.1
This “read/write” bit field allows the user to transmit a
Yellow Alarm to the “Far-End” Receive DS3 Framer
Transmit Yellow Alarm—Bit 7
via software control. If the user opts to transmit a
“Yellow Alarm” then all of the X-bits, in the outbound
DS3 frames will be set to ‘0’. The following table re-
lates the content of this bit field to the Transmit DS3
Framer’s action.
Note:
This bit is ignored when either the “TxIDLE”,
“TxAIS”, or the “TxLOS” bit-fields are set.
6.4.4.2.2
This bit field functions as the logical complement of
Bit 7. This “read/write” bit field allows the user to
Transmit X-bit—Bit 6
force all of the X-bits, in the outgoing DS3 frame, to
“1” and transmit them to the “Far-End” Receiver. The
following table relates the content of this bit field to
the Transmit DS3 Framer’s action.
Note:
This bit is ignored when either the Transmit Yellow
Alarm, Tx AIS, Tx IDLE, or TxLOS bit is set.
6.4.4.2.3
This “read/write” bit field allows the user to transmit an
“Idle Condition” pattern to the “Far-End” Receiver upon
Transmit Idle (Condition) Pattern—Bit 5
software control. The following table relates the
contents of this bit field to the Transmit DS3 Framer’s
action.
Tx DS3 Configuration Register (Address = 16h)
B
IT
7
B
IT
6
B
IT
5
B
IT
4
B
IT
3
B
IT
2
B
IT
1
B
IT
0
Tx
Yellow
Alarm
Tx X-Bit
Tx IDLE
Pattern
Tx AIS
Pattern
Tx LOS
Pattern
FERF on
LOS
FERF on
OOF
FERF on AIS
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
T
ABLE
35: T
HE
R
ELATIONSHIP
BETWEEN
THE
CONTENTS
OF
B
IT
7 (T
X
Y
ELLOW
A
LARM
)
WITHIN
THE
T
X
DS3
C
ONFIGURATION
R
EGISTER
,
AND
THE
RESULTING
T
RANSMIT
DS3 F
RAMER
A
CTION
B
IT
7
T
RANSMIT
DS3 F
RAMER
’
S
A
CTION
0
Normal Operation:
The X-bits are generated by the UNI based upon “Near End” Receiving Conditions”
(via the Receive DS3 Framer of the UNI chip)
1
Transmit Yellow Alarm:
The Transmit DS3 Framer will overwrite the X-bits by setting them all to “0”. The
payload information is not modified and is transmitted as normal.
T
ABLE
36: T
HE
R
ELATIONSHIP
BETWEEN
THE
CONTENTS
OF
B
IT
6 (T
X
X-B
ITS
)
WITHIN
THE
T
X
DS3 C
ONFIGURATION
R
EGISTER
,
AND
THE
RESULTING
T
RANSMIT
DS3 F
RAMER
A
CTION
B
IT
6
T
RANSMIT
DS3 F
RAMER
’
S
A
CTION
0
Normal Operation:
The X-bits are generated by the UNI based upon “Receiving Conditions” (via the Receive
Section of the UNI chip)
1
Set X-bits to “1”.
The Transmit DS3 Framer will overwrite the X-bits by setting them to “1”. Payload informa-
tion is not modified and is transmitted as normal.