RELEASED
PM7350 S/UNI DUPLEX
DATA SHEET
PMC-1980581
ISSUE 8
DUAL SERIAL LINK PHY MULTIPLEXER
Far-End
Near-End
Resultant Cell contents at far-end Bus or Microprocessor
input
Reg
output
Reg 0x14
LVDS: both ends must match e.g. Reg 0x40, 0x50 and 0x60
0x0C
S
C
I
A
N
Y
H
5
U
D
F
P
S
C
I
A
N
Y
H
5
U
D
F
I
P
R
E
L
E
N
[1
..
DEFAULT CONFIGURATION
5 system, 2 prepend, 4 header and 48 data bytes
R
E
L
E
N
[1
..
N
A
D
D
U
D
F
•
•
USRHDR:
PREPEND:
CELLCRC:
4
1
1
Control cell prepend byte 2 is carried as is, but prepend
byte 3 is overwritten with the CRC8. Header bytes 8&9
are undefined.
0]
0]
1
1
1
0
1
1
1
1
0
1
•
Cells are transferred from a 53/53/54(54/54/56) byte bus
to a 54/55/55(56/58/58) byte bus.
At far-end the prepend and H5/UDF fields are all
present. The first byte the prepend is undefined, the
second byte contains the CRC8 from the previous cell.
H5 (H5/UDF) is undefined.
Cells are transferred from the CSD receive port to a
54/55/55(56/58/58) byte bus.
At far-end the prepend and H5/UDF fields are all
present. The first byte the prepend is undefined, the
second byte contains the CRC8 from the previous cell.
H5 (H5/UDF) is undefined
•
X
X
0
1
•
•
1
1
1
1
1
0
0
1
X
X
X
1
X
1
•
Cells are transferred from a 54/54/55(56/56/58) byte bus
to the CSD transmit port.
THIS CONFIGURATION IS VALID ONLY IF OMASTER=0
AND OANYPHY=0 AT THE FAR-END.
Cells are transferred from a 53/53/54(54/54/56) byte bus
to a XX/54/XX(XX/56/XX) byte bus (SCI-ANY slave
only).
•
•
At far-end the prepend(s) and H5(H5/UDF) fields are all
present. The first byte the prepend is undefined, the
second byte (OBUS8=0) contains the CRC8 from the
previous cell.
•
At far-end the H5 (H5/UDF) field contains the PHY
address.
12.3 Maximum Cell Bit Rate
The maximum cell bit rate transferred over the LVDS link is a function the LVDS
bit rate and the ratio of transport overhead (system prepend & unused user
defined field) versus cell data. Since the system prepend is fixed at 5 bytes, the
absolute maximum throughput is achieved when the cell length is 56 bytes, i.e.
the transported cells included 2 prepend bytes, H5 and UDF.
Ratiomax = 56/61 = 91.8%, CellBRmax = 91.8% * 200 = 183.6 Mb/s
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
195
PMC [ PMC-SIERRA, INC ]
