KSZ8862-16_10 MICREL [Micrel Semiconductor], KSZ8862-16_10 Datasheet - Page 70

• Manufacturer Part Number: KSZ8862-16_10
• Description: 2-Port Ethernet Switch with Non-PCI Interface and Fiber Support
• Manufacturer: MICREL [Micrel Semiconductor]

Bank 32 Switch Global Control Register 2 (0x04): SGCR2
This register contains the global control for the switch function.
Micrel, Inc.
August 2010
Bit
15
14
13
12
11
10-9
8
7
6
5
4
3
2
0
0
0
0
0
0
1
1
1
1
0
0
Default
0x0
R/W
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
Description
802.1Q VLAN Enable
1 = 802.1Q VLAN mode is turned on. VLAN table must be set up before the operation.
0 = 802.1Q VLAN is disabled.
IGMP Snoop Enable On Switch Host port
1 = IGMP snoop is enabled.
All the IGMP packets are forwarded to the Switch host port.
0 = IGMP snoop is disabled.
Ipv6 MLD Snooping Enable
1 = enable IPv6 MLD snooping
Ipv6 MLD Snooping Option
1 = enable IPv6 MLD snooping option
Priority Scheme Select
0 = always TX higher priority packets first.
1 = Weighted Fair Queueing enabled. When all four queues have packets waiting to transmit, the
bandwidth allocation is q3:q2:q1:a0 = 8:4:2:1.
If any queues are empty, the highest non-empty queue gets one more weighting. For example, if q2
is empty, q3:q1:q0 becomes (8+1): 0:2:1.
Reserved
Sniff Mode Select
1 =performs RX and TX sniff (both the source port and destination port need to match).
0 = performs RX or TX sniff (either the source port or destination port needs to match). This is the
mode used to implement RX only sniff.
Unicast Port-VLAN Mismatch Discard
1 = no packets can cross the VLAN boundary.
0 = unicast packets (excluding unknown/multicast/broadcast) can cross the VLAN boundary.
Multicast Storm Protection Disable
1 = “Broadcast Storm Protection” does not include multicast packets. Only DA = FFFFFFFFFFFF
packets are regulated.
0 = “Broadcast Storm Protection” includes DA = FFFFFFFFFFFF and DA[40] = 1 packets.
Back Pressure Mode
1 = carrier sense-based Back Pressure is selected.
0 = collision-based Back Pressure is selected.
Flow Control And Back Pressure Fair Mode
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 prevents 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 is flow controlled. This may not be “fair” to the flow control port.
No Excessive Collision Drop
1 = the switch does not drop packets when 16 or more collisions occur.
0 = the switch drops packets when 16 or more collisions occur.
Huge Packet Support
1 = accepts packet sizes up to 1916 bytes (inclusive). This bit setting overrides setting from bit 1 of
the same register.
0 = the max packet size is determined by bit 1 of this register.
70
KSZ8862-16/32MQL
M9999-081310-3.1