High Performance Two Port 10/100 Managed Ethernet Switch with 32-Bit Non-PCI CPU Interface
Datasheet
14.5.4.13 Buffer Manager Egress Port Type Register (BM_EGRSS_PORT_TYPE)
Register #:
1C0Ch
Size:
32 bits
This register is used to configure the egress VLAN tagging rules. See Section 6.5.6, "Adding,
Removing, and Changing VLAN Tags," on page 79 for additional details.
BITS
DESCRIPTION
TYPE
DEFAULT
31:22
21
RESERVED
RO
-
Insert Tag Port 2
R/W
0b
When set, untagged packets will have a tag added that contains the Default
VLAN ID and Priority of the ingress port.
The un-tag bit in the VLAN table for the default VLAN ID also needs to be
cleared in order for the tag to be inserted.
This is only used when the Egress Port Type is set as Hybrid.
20
Change VLAN ID Port 2
When set, regular tagged packets will have their VLAN ID overwritten with
the Default VLAN ID of the egress port.
R/W
0b
The Change Tag bit also needs to be set.
The un-tag bit in the VLAN table for the incoming VLAN ID also needs to be
cleared, otherwise the tag will be removed instead.
Priority tagged packets will have VLAN ID overwritten with the Default VLAN
ID of the ingress port independent of this bit.
This is only used when the Egress Port Type is set as Hybrid.
19
Change Priority Port 2
R/W
0b
When set, regular tagged packets will have their Priority overwritten with the
Default Priority of the egress port. Priority tagged packets will have VLAN ID
overwritten with the Default VLAN ID of the ingress port.
For regular tagged packets, the Change Tag bit also needs to be set.
The un-tag bit in the VLAN table for the incoming VLAN ID also needs to be
cleared, otherwise the tag would be removed instead.
This is only used when the Egress Port Type is set as Hybrid.
18
Change Tag Port 2
When set, allows the Change Tag and Change Priority bits to affect regular
tagged packets.
R/W
0b
This bit has no affect on priority tagged packets.
This is only used when the Egress Port Type is set as Hybrid.
Revision 1.2 (04-08-08)
424
SMSC LAN9312
DATASHEET
SMSC [ SMSC CORPORATION ]
