TNETE2008

OctalPHY

EIGHT 10BASE-T PHYSICAL-LAYER INTERFACES

SPWS042B – DECEMBER 1997 – REVISED JUNE 1998

16

POST OFFICE BOX 655303

bit ordering within nibbles

Normally, network packet data is transferred from the TNETE2008 to the MAC for a particular PHY when, during

its time slot, IFRXDV and IFLINK are both high. There is an opportunity to send other information to the MAC

when either of these two signals is not high. Similarly, the MAC transfers packet information to a particular PHY

in the TNETE2008 when IFLINK and IFTXEN are both high during that PHY’s time slot. There is an opportunity

to send other information to TNETE2008 when either of these two signals is not high.

Currently, the only extended data used in this interface is sending allowed autonegotiating modes to the PHY

channels when IFTXEN and IFLINK are both low, and reporting mode, when autonegotiation is successfully

completed, and when IFLINK and IFRXDV both are low.

Table 1 shows the possible classes of data based on IFLINK and IFTXEN for data to the TNETE2008 from the

MAC, and based on IFLINK and IFRXDV for data from the TNETE2008 to the MAC.

Table 1. Transmit and Receive Data Nibbles

IFLINK

IFTXEN

IFTXD3–IFTXD0

COMMENT

0

0

0000–1111

Extension-specific information

0

1

Reserved

Reserved for future extension

1

0

0000

Normal interframe

1

0

0001–1111

Reserved

1

1

0000–1111

Normal data transmission

IFLINK

IFRXDV

IFRXD3–IFRXD0

COMMENT

0

0

0000–1111

Extension-specific information

0

1

Reserved

Reserved for future extension

1

0

0000

Normal interframe

1

0

0001–1111

Reserved

1

1

0000–1111

Normal data transmission

Figure 7 defines the bits-to-nibble-to-byte ordering and translation used in the multiplexed interface.

D0

D1

D2

D3

D4

D5

D6

D7

LSB D(0)

D(1)

D(2)

MSB D(3)

First Nibble

LSB

MSB

Second Nibble

MAC Serial Bit Stream

First Bit

TNETE2008

Nibble Stream

Figure 7. Data Stream