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DS3/E3 FRAMER IC
XRT7250
REV. 1.1.1
71
This Reset-upon-Read bit-field will be set to "1" if a
Receipt of New Trail Trace Buffer Message interrupt
has occurred since the last read of this register.
The Receive E3 Framer will generate the Receipt of
New Trail Trace Buffer Message interrupt, if it receives
an E3 frame in which the value of the TR byte-field is
of the form "1xxxxxxxb". A TR byte-field value of this
form is identified as the frame start marker.
NOTE: Please see Section 5.3.6.1.6 for a more detailed dis-
cussion of this interrupt.
Bit 4 - FEBE (Far-End Block Error) Interrupt Status
This Reset-upon-Read bit-field will be set to "1" if the
FEBE (Far-End-Block Error) interrupt has occurred
since the last read of this register.
The Receive E3 Framer will generate the FEBE inter-
rupt anytime it detects a "1" in the FEBE bit-field with-
in an incoming E3 frame.
NOTE: Please see Section 5.3.6.1.8 for a more detailed dis-
cussion of this interrupt.
Bit 3 - FERF Interrupt Status
This Reset Upon Read bit will be set to '1' if the Re-
ceive E3 Framer has detected a Change in the Rx
FERF Condition, since the last time this register was
read.
This bit-field will be asserted under either of the fol-
lowing two conditions.
1. When the Receive E3 Framer first detects the
occurrence of an RxFERF Condition (e.g., when
the FERF bit, within the last 3 or 5 consecutive
E3 frames are set to "1").
2. When the Receive E3 Framer detects the end of
the RxFERF Condition (e.g., when the FERF bit,
within the last 3 or 5 consecutive E3 frames are
set to "0").
NOTE: For more information on the RxFERF (Yellow Alarm)
condition, please see Section 5.3.2.6.3.
Bit 2 - EM (BIP-8) Byte Error Interrupt Status
This Reset-upon-Read bit-field will be set to "1" if the
BIP-8 Error interrupt has occurred since the last read
of this register.
The Receive E3 Framer will generate the BIP-8 Error
interrupt if it has concluded that it has received an er-
rored E3 frame, from the Far-End Terminal.
NOTE: Please see Section 5.3.6.1.9 for a more detailed dis-
cussion of this interrupt.
Bit 1 - Framing Byte Error Interrupt Status
This Reset-upon-Read bit-field will be set to "1" if the
Framing Byte Error interrupt has occurred since the
last read of this register.
The Receive E3 Framer will generate the Framing
Byte Error interrupt if it has detected an error in the
FA1 or FA2 bytes, on an incoming E3 frame.
NOTE: Please see Section 5.3.6.1.10 for a more detailed
discussion of this interrupt.
Bit 0 - Rx Pld Mis Interrupt Status
This Reset-upon-Read bit-field will be set to "1" if the
Payload Type Mismatch interrupt has occurred since
the last read of this register.
The Receive E3 Framer will generate the Payload
Type Mismatch interrupt when it detects that the val-
ues, within the Payload Type bit-fields of the incoming
E3 frame, has changed from that of the previous E3
frame.
NOTE: Please see Section 5.3.6.1.11 for a more detailed
discussion on this interrupt.
2.3.3.7
Receive E3 LAPD Control Register (E3,
ITU-T G.832)
Bit 3 - DL from NR
This Read/Write bit-field allows the user to specify
whether the LAPD Receiver should retrieve the bytes,
comprising the incoming LAPD Message frame, from
the NR byte-field, or from the GC byte-field, within
each incoming E3 frame.
Writing a "1" configures the LAPD Receiver to re-
trieve the incoming LAPD Message frame octets from
the NR byte-field, within each incoming E3 frame.
Writing a "0" configures the LAPD Receiver to re-
trieve the incoming LAPD Message frame octets from
the GC byte.
RXE3 LAPD CONTROL REGISTER (ADDRESS = 0X18)
BIT 7BIT 6BIT 5BIT 4BIT 3BIT 2BIT 1BIT 0
Not Used
DL from NR
RxLAPD
Enable
RxLAPD
Interrupt
Enable
RxLAPD
Interrupt
Status
RO
R/W
RUR
0
0000
000