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TC9208M
Preliminary Data Sheet
11.3.3
Port [X] IFG Configuration Register
Confidential.
33/53
August 1, 2003
Copyright © 2003, IC Plus Corp.
TC9208M-DS-R06
- Addresses: 19h – 20h
7 6 5 4 3 2 1 0
IFGConfig
RedGbBndw
GbBndwSel
not used
IFGConfigP[x]
Bit(s)
Field
Description
3 - 0
IFGConfig
Interframe Gap Configuration
4
RedGbBndw
Reduced gigabit bandwidth
6 – 5
GbBndwSel
Gigabit bandwidth selection
7
not used
not used
IFGConfig
These bits are used to set the minimum IFG with 32 bit time resolution. The default
matches the standard minimum IFG of 96 bit time: ‘0011’ (3).
IFGConfig
IFG (bit time)
0001
32
0010
64
0011
96 (default)
0100
128
…
…
1111
480
0000
512
RedGbBndw
Setting this bit to '1', will enable a 1000Mbps port to reduce its transmission
bandwidth to the percentage indicated by the GbBndwSel field. Setting this bit to
‘0’, the GbBndwSel field will be meaningless and the port will make use of its full
transmission bandwidth. This bit is in effect only when the port’s speed mode is
1000Mbps. Default is ‘0’.
GbBndwSel
Transmission bandwidth enforcement when in 1000 Mbps mode.
GbBndwSel
Transmission bandwidth
00
50%
01
66%
10
80%
11
90%
This feature can be used to avoid congestion in some LAN nodes without flow
control capabilities or to avoid server overloads