Intel IXF1104 User Manual
Page 205
Intel
®
IXF1104 4-Port Gigabit Ethernet Media Access Controller
205
Datasheet
Document Number: 278757
Revision Number: 009
Revision Date: 27-Oct-2005
Table 134. TX FIFO MAC Threshold Register Ports 0 - 3 ($0x614 – 0x617)
Name
Description
Address
Type
1
Default
TX FIFO MAC
Threshold Port 0
MAC threshold for TX FIFO Port 0. The
default value of 0x1BE represents 446 8-byte
locations. This equates to 3568 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 reaches this threshold, data is forwarded
to the MAC core and line-side interfaces for
onward transmission. By setting the threshold to
an appropriate value, the user can configure the
TX FIFO to operate in a “cut-through” mode
rather than the default “store and forward”
operation mode.
0x614
R/W
0x000001BE
TX FIFO MAC
Threshold Port 1
MAC threshold for TX FIFO Port 1. The
default value of 0x1BE represents 446 8-byte
locations. This equates to 3568 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 reaches this threshold, data is forwarded
to the MAC core and line-side interfaces for
onward transmission. By setting the threshold to
an appropriate value, the user can configure the
TX FIFO to operate in a “cut-through” mode
rather than the default “store and forward”
operation mode.
0x615
R/W
0x000001BE
TX FIFO MAC
Threshold Port 2
MAC threshold for TX FIFO Port 2. The
default value of 0x1BE represents 446 8-byte
locations. This equates to 3568 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 reaches this threshold, data is forwarded
to the MAC core and line-side interfaces for
onward transmission. By setting the threshold to
an appropriate value, the user can configure the
TX FIFO to operate in a “cut-through” mode
rather than the default “store and forward”
operation mode.
0x616
R/W
0x000001BE
TX FIFO MAC
Threshold Port 3
MAC threshold for TX FIFO Port 3. The
default value of 0x1BE represents 446 8-byte
locations. This equates to 3568 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 reaches this threshold, data is forwarded
to the MAC core and line-side interfaces for
onward transmission. By setting the threshold to
an appropriate value, the user can configure the
TX FIFO to operate in a “cut-through” mode
rather than the default “store and forward”
operation mode.
0x617
R/W
0x000001BE
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