
x r
PRELIMINAZRY
E3 UNI FOR ATM
XRT7234
REV. P1.0.0
71
3.3.2.40 Rx E3 LAPD Control Register
Bit 1–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 retrieve the incoming LAPD Message frame octets from the NR byte-field,
within each incoming E3 frame. Writing a “0” configures the LAPD Receiver to retrieve the incoming LAPD Message
frame octets from the GC byte.
Bit 0—RxLAPD Enable
This “Read/Write” bit-field allows the user to enable or disable the LAPD Receiver, for reception of incoming LAPD
Message frames from the “Far-End” LAPD Transmitter.
Writing a “1” to this bit-field enables the LAPD Receiver. Writing a “0” to this bit-field disables the LAPD Receiver.
3.3.2.41 Rx E3 LAPD Status Register
Bit 6—Rx Abort
This “Read-Only” bit-field indicates whether or not the LAPD Receiver is currently detecting an abort sequence
(e.g., a string of 7 consecutive “1s”).
This bit-field is set to “1” if the LAPD Receiver is currently detecting an abort sequence in the incoming LAPD
Channel. Conversely, this bit-field is set to “0” if the LAPD Receiver has not detected an abort sequence, since the
last read of this register.
Bit 5, 4—RxLAPD Type[1:0]
These two “Read-Only” bit-fields combine to indicate the type and size of LAPD Message frame that has been
Address = 26h, Rx E3 LAPD Control Register
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Unused
DL From NR
RxLAPD Enable
RO
RO
RO
RO
RO
RO
R/W
R/W
0
0
0
0
0
0
0
0
Address = 27h, Rx E3 LAPD Status Register
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Unused
Rx Abort
RxLAPD Type[1:0]
Rx CR Type
Rx FCS
Error
EndOf
Message
Flag Present
RO
RO
RO
RO
RO
RO
RO
RO
0
0
0
0
0
0
0
0