DM9016
3-port switch with Processor Interface
z
z
z
IPv6 Multicast packets.
(1). Disable State:
The Hop Limit in IPv6 header is 1.
z
z
Setting: Reg6CH[5:4] = 2’b01
The Next Header in IPv6 header is 0x3A (ICMPv6) or
0x00 (and next header of hop-by-hop option header is
0x3A).
Description: The port will neither receive
nor transmit any packets. Learning is
disabled.
z
The Type in ICMP header is 0x82 (Multicast Listener
Query), 0x83 (Multicast Listener Report) or 0x84
(Multicast Listener Done).
z
Software Action: None.
(2). Blocking State:
z
z
Setting: Reg6CH[5:4] = 2’b11
9.2.20 Spanning Tree Protocol Support
Description: Only the BPDUs or
overriding packet will be received and
transmitted. Leaning is disabled.
The DM9016 supports Spanning Tree Protocol and
provides four types of port state, Forwarding, Disable,
Learning and Blocking/Listening, see the Port
Security
function
&
STP Register (Reg6CH.[1:0]). This
needs the cooperation
z
Software Action: In order to establish
spanning tree, the receiving BPDUs will be
forward to processor port but the
processor should not send BPDUs to the
port in this state.
n with external CPU. The following figure is the port
state diagram of Spanning Tree Protocol.
(3). Listening State:
z
z
Setting: Reg6CH[5:4] = 2’b11
Description: Only the BPDUs and
overriding packet will be received and
transmitted. Leaning is disabled.
Power-on
Initialization
z
Software Action: The receiving BPDUs
will be forward to processor port and the
processor can send BPDUs to the port in
this state.
Blocking
State
(4). Learning State:
z
z
Setting: Reg6CH[5:4] = 2’b10
Listening
State
Disabled
State
Description: Only the BPDUs and
overriding packet will be received and
transmitted. Leaning is enabled.
z
Software Action: The receiving BPDUs
will be forward to processor port and the
processor can send BPDUs to the port in
this state.
Learning
State
(5). Forwarding State:
Forwarding
State
z
z
Setting: Reg6CH[5:4] = 2’b00
Description: The port participates in
frame relay, learning, and STA calculation.
z
Software Action: The receiving BPDUs
will be forward to processor port and the
processor can send BPDUs to the port in
this state.
Preliminarydatasheet
71
DM9016-13-DS-P01
March 26, 2009
DAVICOM [ DAVICOM SEMICONDUCTOR, INC. ]
