á
PRELIMINARY
DS3 UNI FOR ATM
XRT7245
REV. 1.03
59
3.3.2
This section provides a functional description of each
bit-field within each of the on-chip UNI Registers.
UNI Register Description
Note:
For all on-chip registers, a table containing the bit-
format of the register is presented. Additionally these tables
also contain the default values for each of these register
bits. Finally, the functional description associated with each
register bit-field is presented, along with a reference to a
Section Number, within this Data Sheet, that provides a
more in-depth discussion of the functions associated with
this register bit-field.
3.3.2.1
UNI Operating Mode Register
6Ch
RxUT Address
RxUT Address (R/W portion only)
Combination of R/O
and R/W
6Dh
RxUT FIFO Status Register
R/O
6Eh
TxUT Interrupt Status Register
TxUT Interrupt Status Register (R/W
portion only)
Combination of R/O
and R/W
6Fh
TxUT UDF2 Register
R/O
70h
TxUT Address
TxUT Address (R/W portion only)
Combination of R/O
and R/W
71h
TxUT FIFO Status Register
R/O
72h
Line Interface Drive Register
Line Interface Drive Register (R/W
portion only)
Combination of R/O
and R/W
73h
Line Interface Scan Register
R/O
74h
PMON CP Bit Error Count Register—
MSB
RUR
75h
PMON CP Bit Error Count Register—LSB
RUR
76h
One Second—CP Bit Error Accumalation
Register—MSB
RO
77h
One Second—CP Bit Error Accumalation
Register—LSB
RO
78h–85h
Unused
Unused
—
86h–DDh
Transmit LAPD Message Buffer (88 bytes
of on-chip RAM)
Transmit LAPD Message Buffer (88
bytes of on-chip RAM)
R/W
DEh–135h
Receive LAPD Message Buffer (88 bytes
of on-chip RAM)
Receive LAPD Message Buffer (88
bytes of on-chip RAM)
R/W
136h–16Bh
Transmit OAM Cell Buffer (54 bytes of on-
chip RAM)
Transmit OAM Cell Buffer (54 bytes of
on-chip RAM)
R/W
16Ch–1A1h
Receive OAM Cell Buffer (54 bytes of on-
chip RAM)
Receive OAM Cell Buffer (54 bytes of
on-chip RAM)
R/W
T
ABLE
4: R
EGISTER
A
DDRESSING
OF
THE
UNI P
ROGRAMMABLE
R
EGISTERS
(C
ONT
’
D
)
A
DDRESS
R
EAD
M
ODE
R
EGISTER
W
RITE
M
ODE
R
EGISTER
R
EGISTER
T
YPE
Address = 00h, UNI Operating Mode Register
B
IT
7
B
IT
6
B
IT
5
B
IT
4
B
IT
3
B
IT
2
B
IT
1
B
IT
0
Line Loop
Back
Cell Loop
Back
PLCP Loop
Back
Reset
Direct-
Mapped ATM
M13/C-Bit*
TimRef
Sel(1)
TimRef
Sel(0)
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
0
0
0
0
1
0
1
1