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MVTX2803
Data Sheet
34
Zarlink Semiconductor Inc.
10.2 Group 0 Address - MAC Ports Group
10.2.1 ECR1Pn: Port N Control Register
I
2
C Address h00+2n; Serial Interface Address:h000+2n (n=0 to 7)
Accessed by serial interface and I
2
C (R/W)
7
6
5
4
3
2
1
0
Sp State
A-FC
Port Mode
Bit [4:0]
Port Mode (Default 2’b00)
Bit [4:3]
00 - Automatic Enable Auto-Negotiation – This enables hardware state machine for auto-negotiation.
01 - Limited Disable auto-Negotiation – This disables hardware for speed auto-negotiation.
Hardware Polls MII for link status.
10 - Link Down - Force link down (disable the port). Does not talk to PHY.
11 - Link Up – Does not talk to PHY. User ERC1 [2:0] for config.
Bit [2]
1 – 10Mbps (Default 1’b0)
0 – 100Mbps
Bit 2 is used only when the port is in MII (10/100) mode.
Bit [1]
1 – Half Duplex (Do not use)
(Default 1’b0)
0 – Full Duplex
Bit [0]
1 – Flow Control Off
(Default 1’b0)
0 – Flow Control On
When flow control is on:
In full duplex mode, the MAC transmitter sends Flow Control Frames when necessary. The MAC
receiver interprets and processes incomming flow control frames. The Flow Control Frame Received
counter is incremented whenever a flow control frame is received.
When flow control is off:
In full duplex mode, the MAC transmitter does not send flow control frames. The MAC receiver does
not interpret or process the flow control frames. The Flow Control Frame Receiver counter is not
incremented.
Bit [5]
Asymmetric Flow Control Enable.
0 – Disable asymmetric flow control
1 – Enable asymmetric flow control
When this bit is set, and flow control is on (bit[0] = 0), don’t send out a flow control frame. But MAC
Receiver interprets and process flow control frames.
(Default is 0)
Bit [7:6]
SS - Spanning tree state (802.1D spanning tree protocol).
(Default 2’b11)
00 – Blocking:
Frame is dropped
01 - Listening:
Frame is dropped
10 - Learning:
Frame is dropped. Source MAC address is learned.
11 - Forwarding: Frame is forwarded. Source MAC address is learned.