KSZ8893-MQL Micrel Semiconductor, Inc., KSZ8893-MQL Datasheet - Page 56

• Manufacturer Part Number: KSZ8893-MQL
• Description: Integrated 3-Port 10/100 Managed Switch with PHYs
• Manufacturer: Micrel Semiconductor, Inc.

Register 3 (0x03): Global Control 1
Bit
7
6
5
4
3
2
1
0
Register 4 (0x04): Global Control 2
Bit
7
6
5
Micrel
November 2005
Name
Pass All
Frames
Reserved
IEEE 802.3x
Transmit
Direction Flow
Control Enable
IEEE 802.3x
Receive
Direction Flow
Control Enable
Frame Length
Field Check
Fast Age
Enable
Aggressive
Back-off
Enable
Name
Unicast
Port-VLAN
Mismatch
Discard
Multicast
Storm
Protection
Disable
Mode
Aging Enable
Back Pressure
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
Description
= 1, switch all packets including bad ones. Used
solely for debugging purposes. Works in conjunction
with sniffer mode only.
Reserved
Do not change the default value.
= 1, will enable transmit direction flow control feature.
= 0, will not enable transmit direction flow control
feature. Switch will not generate any flow control
(PAUSE) frame.
= 1, will enable receive direction flow control feature.
= 0, will not enable receive direction flow control
feature. Switch will not react to any flow control
(PAUSE) frame it receives.
1 = will check frame length field in the IEEE packets.
If the actual length does not match, the packet will be
dropped (for Length/Type field < 1500).
1 = enable age function in the chip
0 = disable age function in the chip
1 = turn on fast age (800us)
1 = enable more aggressive back off algorithm in half
duplex mode to enhance performance. This is not an
IEEE standard.
Description
This feature is used with port-VLAN (described in reg.
17, reg. 33, …)
= 1, all packets can not cross VLAN boundary
= 0, unicast packets (excluding unkown/multicast/
broadcast) can cross VLAN boundary
Note: Port mirroring is not supported if this bit is set to
“0”.
= 1, “Broadcast Storm Protection” does not include
multicast packets. Only DA = FF-FF-FF-FF-FF-FF
packets will be regulated.
= 0, “Broadcast Storm Protection” includes
DA = FF-FF-FF-FF-FF-FF and DA[40] = 1 packets.
= 1, carrier sense based backpressure is selected
= 0, collision based backpressure is selected
56
Default
0
0
1
1
0
0
0
0
Default
1
1
1
KSZ8893MQL/MQLI
M9999-111705