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16

Revision 1.0

3.3

PORT STATUS: PAGE 0, PORTS[0:2]

The Port Status page is accessed by setting the

Page_select field to 000b in the Base register at Address

07h. Status information is selected per-port within the Port

Status page by setting the Port_select field in the Base reg-

ister at Address 07h. Three sets of port status registers,

one per-port, are indexed by the Port_select field. Valid

Port_select values are 000b, 001b, and 010b.

Table 3-6. Port Status: Page 0 Bit Map

Address

01234

567

08h

AStat

BStat

Child

Connected

Bias

Disabled

09h

Negotiated_speed

Int_Enable

Fault

RSVD

0Ah-0Fh

RSVD

Table 3-7. Port Status: Page 0 Registers

Bit

Name

Access

Reset

Description

Address 08h

Page 0, Port[n], Register-0

0:1

AStat

R

Undef

TPA Status: TPA differential line state detected by the TPA arbitration com-

parators of the port specified by Port_select.

00 = Invalid

01 = 1

10 = 0

11 = Z

2:3

BStat

R

Undef

TPB Status: TPB differential line state detected by the TPB arbitration com-

parators of the port specified by Port_select.

00 = Invalid

01 = 1

10 = 0

11 = Z

4

Child

R

Undef

Child: When set, the port specified by Port_select is a child. If clear, the port

is a parent.

5

Connected

R

0

Connected: When set, the port specified by Port_select is connected.

6

Bias

R

Undef

Bias: When set, the port specified by Port_select detects TPBias from a

connected PHY.

7

Disabled

RW

0

Disable: When set, the port specified by Port_select is disabled.

Address 09h

Page 0, Port[n], Register-1

0:2

Negotiated_ speed

R

Undef

Negotiated Speed: The maximum negotiated speed between the port spec-

ified by Port_select and a connected port.

000 = 100 Mbits/sec

001 = 200 Mbits/sec

010 = 400 Mbits/sec

All other settings are reserved.

3

Int_Enable

RW

0

Interrupt Enable: When set, the port specified by Port_select, port event

interrupts are enabled. A change in connected, bias, disabled, or fault states

will set the Port_event bit.

4

Fault

RW

0

Fault: A Suspend or Resume operation error of the port specified by

Port_select will set this bit. Writing a one to the bit will clear it to zero.

5:7

RSVD

--

--

Reserved

Address 0Bh-0Fh

Page 0, Port[n], Register-2 through Register-7

0:7

RSVD

RW

00h

Reserved: Do not set bits in these fields. Setting bits in these fields may

cause noncompliant or unspecified behavior.