KSZ8993M-EVAL Micrel Inc, KSZ8993M-EVAL Datasheet - Page 51

• Manufacturer Part Number: KSZ8993M-EVAL
• Description: KSZ8993M Evaluation Board - For Experimental Use Only
• Manufacturer: Micrel Inc

Specifications of KSZ8993M-EVAL

• Lead Free Status / RoHS Status: Supplier Unconfirmed

Register 4 (0x04): Global Control 2 (continued)
Bit
4
3
2
1
0
Register 5 (0x05): Global Control 3
Bit
7
6
5
4
3-2
1
Micrel, Inc.
October 2008
Flow control
and back
pressure fair
mode
No excessive
collision drop
Huge packet
support
Legal
Maximum
Packet size
check enable
Priority Buffer
reserve
802.1Q VLAN
enable
IGMP snoop
enable on
Switch MII
interface
Reserved
Reserved
Priority
Scheme select
Reserved
Name
Name
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, fair mode is selected. In this mode, if a flow
control port and a non-flow control port talk to the
same destination port, packets from the non-flow
control port may be dropped. This is to prevent the
flow control port from being flow controlled for an
extended period of time.
= 0, in this mode, if a flow control port and a non-flow
control port talk to the same destination port, the flow
control port will be flow controlled. This may not be
“fair” to the flow control port.
= 1, the switch will not drop packets when 16 or more
collisions occur.
= 0, the switch will drop packets when 16 or more
collisions occur.
= 1, will accept packet sizes up to 1916 bytes
(inclusive). This bit setting will override setting from
bit 1 of the same register.
= 0, the max packet size will be determined by bit 1 of
this register.
= 0, will accept packet sizes up to 1536 bytes
(inclusive).
= 1, 1522 bytes for tagged packets, 1518 bytes for
untagged packets. Any packets larger than the
specified value will be dropped.
= 1, each output queue is pre-allocated 48 buffers,
used exclusively for high priority packets. It is
recommended to enable this when priority queue
feature is turned on.
= 0, no reserved buffers for high priority packets.
Description
= 1, 802.1Q VLAN mode is turned on. VLAN table
needs to set up before the operation.
= 0, 802.1Q VLAN is disabled.
=1, IGMP snoop is enabled.
All the IGMP packets will be forwarded to the Switch
MII port.
=0, IGMP snoop is disabled.
00 = always deliver high priority packets first
01 = deliver high/low packets at ratio 10/1
10 = deliver high/low packets at ratio 5/1
11 = deliver high/low packets at ratio 2/1
51
Default
1
SMAC (pin
69) value
during
reset.
0
SMRXD0
(pin 85)
value
during
reset.
1
Default
0
0
0
0
00
0
M9999-020606
KSZ8993M/ML