IXF1104 4-Port Gigabit Ethernet Media Access Controller
Datasheet 203
Document Number: 278757
Revision Number: 007
Revision Date: March 25, 2004
Table 133. TX FIFO Low Watermark Register Ports 0 - 3 ($0x60A – 0x60D)
Name Description Address Type
1
Default
TX FIFO Low
Watermark Port 0
Low watermark for TX FIFO Port 0. The
default value of 0x0D0 represents 208 8-byte
locations. This equates to 1664 bytes of data. A
unit entry in this register equates to 8 bytes of
data. When the amount of data stored in the TX
FIFO falls below the low watermark, flow control
is automatically de-asserted on the SPI3
interface to allow further data to be sent by the
switch fabric to the IXF1104.
0x60A R/W 0x000000D0
TX FIFO Low
Watermark Port 1
Low watermark for TX FIFO Port 1. The
default value of 0x0D0 represents 208 8-byte
locations. This equates to 1664 bytes of data. A
unit entry in this register equates to 8 bytes of
data. When the amount of data stored in the TX
FIFO falls below the low watermark, flow control
is automatically de-asserted on the SPI3
interface to allow further data to be sent by the
switch fabric to the IXF1104.
0x60B R/W 0x000000D0
TX FIFO Low
Watermark Port 2
Low watermark for TX FIFO Port 2. The
default value of 0x0D0 represents 208 8-byte
locations. This equates to 1664 bytes of data. A
unit entry in this register equates to 8 bytes of
data. When the amount of data stored in the TX
FIFO falls below the low watermark, flow control
is automatically de-asserted on the SPI3
interface to allow further data to be sent by the
switch fabric to the IXF1104.
0x60C R/W 0x000000D0
TX FIFO Low
Watermark Port 3
Low watermark for TX FIFO Port 3. The
default value of 0x0D0 represents 208 8-byte
locations. This equates to 1664 bytes of data. A
unit entry in this register equates to 8 bytes of
data. When the amount of data stored in the TX
FIFO falls below the low watermark, flow control
is automatically de-asserted on the SPI3
interface to allow further data to be sent by the
switch fabric to the IXF1104.
0x60D R/W 0x000000D0
1. RO = Read Only, No clear on Read; R = Read, Clear on Read; W = Write only; R/W = Read/Write, No
clear; R/W/C = Read/Write, Clear on Write