XRT72L52 Datasheet, PDF (123/480 Pages) Exar Corporation – TWO CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER

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TWO CHANNEL DS3/E3 FRAMER IC WITH HDLC CONTROLLER
PRELIMINARY
XRT72L52
REV. P1.1.3
TXE3 MA BYTE REGISTER (ADDRESS = 0X36)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
Transmit MA Byte
FERF
FEBE
Payload Type
R/W
R/W
R/W
R/W
R/W
0
0
0
1
0
BIT 2
BIT 1
Payload Dependent
R/W
R/W
0
0
BIT 0
Timing
Marker
R/W
0
This Read/Write byte-fields permits the user to speci-
fy the contents of the MA byte-field in each outbound
E3 frame.
NOTE: The values written into bit-fields 6 (FEBE) and 7
(FERF) are inserted into outbound E3 frames, only if bit-
field 0 (MAx) within the Tx E3 Configuration Register
(Address = 0x28) is set to "0". Otherwise, the Transmit
DS3/E3 Framer block will set the FERF and FEBE values,
within each outbound E3 frame, to values based upon
Receive DS3/E3 Framer block conditions.
2.4.6.5.2 The “October 1998” Revision
If the channel has been configured to support the
“October 1998” revision of the ITU-T G.832 framing
format for E3; then the bit-format of the “TxE3 MA
Byte” register is as presented below.
TXE3 MA BYTE REGISTER (ADDRESS = 0X36)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
Transmit MA Byte
FERF
FEBE
Payload Type
R/W
R/W
R/W
R/W
R/W
0
0
0
1
0
BIT 2
BIT 1
MFI[1:0]
R/W
R/W
0
0
BIT 0
SSM
R/W
0
This Read/Write byte-fields permits the user to speci-
fy the contents of the MA byte-field in each outbound
E3 frame.
NOTE: The values written into bit-fields 6 (FEBE) and 7
(FERF) are inserted into outbound E3 frames, only if bit-
field 0 (MAx) within the Tx E3 Configuration Register
(Address = 0x28) is set to "0". Otherwise, the Transmit
DS3/E3 Framer block will set the FERF and FEBE values,
within each outbound E3 frame, to values based upon
Receive DS3/E3 Framer block conditions.
2.4.6.6 Transmit E3 NR Byte Register (E3, ITU-
T G.832)
TXE3 NR BYTE REGISTER (ADDRESS = 0X37)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
TxNR[7:0]
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
0
0
0
1
0
0
0
0
This Read/Write byte-field permits the user to specify
the contents of the NR byte-field in each outbound E3
frame.
NOTE: The contents of this register is ignored, if the LAPD
Transmitter is enabled and has been configured to insert
the comprising octets of an outbound LAPD Message
frame into the NR byte-field of each outbound E3 frame
(e.g., if DLinNR = "1").
2.4.6.7 Transmit E3 TTB-0 Register (E3, ITU-T
G.832)
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