PMC-Sierra, Inc.
PRELIMINARY
PM5381 S/UNI-2488
DATASHEET
PMC-2000489
ISSUE 1
SATURN USER NETWORK INTERFACE FOR 2488 MBIT/S
Register 0783H: RXPHY Indirect Burst Size
Bit
Type
Function
Default
Bit 15
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
R
BUSY
X
0
0
0
0
0
0
0
0
0
0
0
0
0
1
1
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
CONFIG_RWB
PHY_ADDR[5]
PHY_ADDR[4]
PHY_ADDR[3]
PHY_ADDR[2]
PHY_ADDR[1]
PHY_ADDR[0]
Reserved
Bit 8
Bit 7
Bit 6
Reserved
Bit 5
Reserved
Bit 4
Reserved
Bit 3
BURST_SIZE[3]
BURST_SIZE[2]
BURST_SIZE[1]
BURST_SIZE[0]
Bit 2
Bit 1
Bit 0
The RXPHY Indirect Burst Size register is an indirect address and data register. The register is
used only in POS mode of operation.
BURST_SIZE[3:0]
The BURST_SIZE data register is provided to program the allowable burst size for the PHY.
The size of a burst is BURST_SIZE + 1. For example, a BURST_SIZE[3:0] = “0000”
indicates a burst size of one block. A block is equal to 16 bytes and takes 4 clocks to transfer.
The 4 bits of Burst Size allow the maximum burst to be 16 blocks (256 bytes), per PHY. This
register is used only in POS-PHY L3 mode.
PHY_ADDR[5:0]
The PHY_ADDR bits are an indirect address that is used with BURST_SIZE data. The two
allow indirect address reads and writes using a small amount of external address space. The
PHY_ADDR is used with CONFIG_RWB and BUSY to command reads and writes. Valid
values for PHY_ADDR[5:0] are from 0 to 2FH. For the S/UNI-2488, PHY_ADDR[5:0] must
be set to zero.
CONFIG_RWB
The CONFIG_RWB register allows the indirect addressing method to specify whether a read
or write is being performed. A value of ‘1’ means that a read is to be performed on the data
Proprietary and Confidentail to PMC-Sierra Inc., and for its Customer’s Internal Use
366
PMC [ PMC-SIERRA, INC ]
