
MVTX2802
Data Sheet
51
Zarlink Semiconductor Inc.
11.3.1.2 ECR2Pn: Port N Control Register
I
2
C Address: 01+2n; CPU Address:h001+2n (n=0 to 3)
Accessed by CPU and serial interface (R/W)
Bit [4:3]
00 - Automatic Enable Auto-Negotiation – This enables hardware state machine for auto-negotiation.
01 - Limited Disable auto-Negotiation – This disables hardware auto-negotiation. Hardware only
Polls MII for link status. Use bit [2:0] for config.
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 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 incoming 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.
7
6
5
3
2
1
0
Security En
DisL
Ftf
Futf
Bit[0]:
Filter untagged frame
(Default 0)
0: Disable
1: Enable – All untagged frames from this port are discarded or follow security option when security is
enable