Texas Instruments TNETX4090 specifications Port to not support pause frames

Models: TNETX4090

1 78
Download 78 pages 14.04 Kb
Page 10
Image 10

TNETX4090

ThunderSWITCH II9-PORT 100-/1000-MBIT/S ETHERNETSWITCH

SPWS044E ± DECEMBER 1997 ± REVISED AUGUST 1999

 

 

 

 

 

Terminal Functions (Continued)

100-/1000-Mbit/s MAC interface [media-independent interface (MII) mode]

 

 

 

 

 

 

 

 

 

 

 

TERMINAL

I/O

INTERNAL

 

 

DESCRIPTION

 

NAME

RESISTOR

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Collision sense. Assertion of M08_COL during half-duplex operation indicates network collision.

 

M08_COL

I

Pulldown

Additionally, during full-duplex operation, transmission of new frames does not commence if this

 

 

 

 

 

terminal is asserted.

 

 

 

 

 

 

 

 

 

 

 

M08_CRS

I

Pulldown

Carrier sense. M08_CRS indicates a frame carrier signal is being received.

 

 

 

 

 

 

 

 

 

 

 

M08_EWRAP

O

None

Enable wrap. M08_EWRAP reflects the state of the loopback bit in the PCS8Control register.

 

 

 

 

 

 

 

 

 

 

 

M08_GTCLK

O

None

Unused. This terminal can be left unconnected.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Connection status. M08_LINK indicates the presence of port connection.

 

M08_LINK

I

Pulldown

± If M08_LINK = 0, there is no link.

 

 

 

 

 

± If M08_LINK = 1, the link is OK.

 

 

 

 

 

 

 

 

 

 

 

 

 

Renegotiate.

 

indicates to the attached PHY device that this device wishes to negotiate

 

 

 

 

 

M08_LREF

 

 

 

 

 

a new configuration.

 

 

 

 

 

 

 

 

 

O

None

± Following a 0-to-1 transition of neg in PortxControl,

M08_LREF

is asserted low, and

 

M08_LREF

 

remains low until M08_LINK goes low. If M08_LINK was already low, M08_LREF is still

 

 

 

 

 

activated for at least one cycle.

 

 

 

 

 

± M08_LREF is asserted low for as long as initd in SysControl = 0, regardless of the state

 

 

 

 

 

of M08_LINK.

 

 

 

 

 

 

M08_RCLK

I

Pullup

Receive clock. Receive clock source from the attached PHY or PMI device.

 

 

 

 

 

 

M08_RFCLK

I

Pullup

Transmit clock. Transmit clock from the attached PHY or PMI device.

 

 

 

 

 

 

 

 

 

 

M08_RXD7

I

Pullup

Unused. These terminals can be left unconnected.

 

M08_RXD6

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

IEEE Std 802.3x pause frame support selection

 

M08_RXD5

I/O²

Pullup

± If pulled low either internally or by the attached PHY or PMI device, M08_RXD5 causes the

 

 

 

 

 

port to not support pause frames.

 

 

 

 

 

± If not pulled low, the port does not support pause frames.

 

 

 

 

 

 

 

 

 

 

 

Duplex selection [force half duplex (active low)]

 

M08_RXD4

I/O²

Pullup

± If pulled low either internally or by the attached PHY or PMI device, the port operates in

 

 

 

 

 

half-duplex mode.

 

 

 

 

 

± If not pulled low, the port operates in full-duplex mode.

 

 

 

 

 

 

 

 

 

 

M08_RXD3

 

 

 

 

 

 

 

 

M08_RXD2

I

Pullup

Receive data. Nibble-wide receive data from the attached PHY or PMI device. When M08_RXDV

 

M08_RXD1

is asserted, these signals carry receive data. Data on these signals is synchronous to M08_RCLK.

 

 

 

 

M08_RXD0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

M08_RXDV

I

Pulldown

Receive data valid. M08_RXDV indicates data on M08_RXD3±M08_RXD0 is valid. This signal is

 

synchronous to M08_RCLK.

 

 

 

 

 

 

 

 

 

 

 

M08_RXER

I

Pulldown

Receive error. Indicates reception of a coding error on received data.

 

 

 

 

 

 

 

 

 

 

M08_TXD7

 

 

 

 

 

 

 

 

M08_TXD6

O

None

Unused. These terminals can be left unconnected, but are driven low.

 

M08_TXD5

 

 

 

 

 

 

 

 

 

M08_TXD4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

M08_TXD3

 

 

 

 

 

 

 

 

M08_TXD2

O

None

Transmit data. Nibble-wide transmit data. When M08_TXEN is asserted, these signals carry

 

M08_TXD1

transmit data. Data on these signals is synchronous to M08_RFCLK.

 

 

 

 

M08_TXD0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

²Not a true bidirectional terminal. It can only be actively pulled down.

10

POST OFFICE BOX 655303 DALLAS, TEXAS 75265

Page 10
Image 10
Texas Instruments TNETX4090 specifications Port to not support pause frames