R

Chapter 9: Configuration and Status

Table 9-30:SGMII Control (Register 0)

Bit(s)

Name

 

Description

Attributes

Default

 

Value

 

 

 

 

 

 

 

 

 

 

 

0.15

Reset

1

= Core Reset

read/write

0

 

 

0

= Normal Operation

self clearing

 

 

 

 

 

 

 

0.14

Loopback

1

= Enable Loopback Mode

read/write

0

 

 

0

= Disable Loopback Mode

 

 

 

 

When used with a RocketIO

 

 

 

 

transceiver, the core is placed in

 

 

 

 

internal loopback mode.

 

 

 

 

With the TBI version, Bit 1 is

 

 

 

 

connected to ewrap. When set to ‘1’

 

 

 

 

indicates to the external PMA

 

 

 

 

module to enter loopback mode.

 

 

 

 

See “Loopback,” page 197.

 

 

 

 

 

 

 

0.13

Speed

Always returns a ‘0’ for this bit.

returns 0

0

 

Selection

Together with bit 0.6, speed selection

 

 

 

(LSB)

of 1000 Mbps is identified

 

 

 

 

 

 

 

0.12

Auto-

1 = Enable SGMII Auto-Negotiation

read/write

1

 

Negotiation

Process

 

 

 

Enable

0 = Disable SGMII Auto-Negotiation

 

 

 

 

 

 

 

 

Process

 

 

 

 

 

 

 

 

0.11

Power Down

1

= Power down

read/ write

0

 

 

0

= Normal operation

 

 

 

 

With the PMA option, when set to ’1’

 

 

 

 

the RocketIO transceiver is placed in

 

 

 

 

a low-power state. This bit requires a

 

 

 

 

reset (see bit 0.15) to clear.

 

 

 

 

With the TBI version this register bit

 

 

 

 

has no effect.

 

 

 

 

 

 

 

 

0.10

Isolate

1

= Electrically Isolate SGMII logic

read/write

1

 

 

from GMII

 

 

 

 

0

= Normal operation

 

 

 

 

 

 

 

 

0.9

Restart Auto-

1

= Restart Auto-Negotiation

read/write

0

 

Negotiation

Process across SGMII link

self clearing

 

 

 

 

 

 

 

 

0

= Normal Operation

 

 

 

 

 

 

 

0.8

Duplex Mode

Always returns a ‘1’ for this bit to

returns 1

1

 

 

signal Full-Duplex Mode

 

 

 

 

 

 

 

0.7

Collision Test

Always returns a ‘0’ for this bit to

returns 0

0

 

 

disable COL test

 

 

 

 

 

 

 

0.6

Speed

Always returns a ‘1’ for this bit.

returns 1

1

 

Selection

Together with bit 0.13, speed

 

 

 

(MSB)

selection of 1000 Mbps is identified

 

 

 

 

 

 

 

 

146

www.xilinx.com

Ethernet 1000BASE-X PCS/PMA or SGMII v9.1

 

 

UG155 March 24, 2008

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Xilinx 1000BASE-X manual Configuration and Status 30SGMII Control Register