Texas Instruments THUNDERSWITCH II TNETX4090 - Manual (Page 9)

TNETX4090
ThunderSWITCH II

9-PORT 100-/1000-MBIT/S ETHERNET

SWITCH
SPWS044E – DECEMBER 1997 – REVISED AUGUST 1999
9
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
Terminal Functions (Continued)
100-/1000-Mbit/s MAC interface [physical media attachment (PMA) mode]
TERMINAL
NAME
I/O
INTERNAL
RESISTOR
DESCRIPTION
M08_COL I Pulldown
Receive byte clock 1. M08_COL is used to input receive byte clock 1 from the attached SERDES
device.
M08_CRS I Pulldown Unused. This terminal can be left unconnected.
M08_EWRAP O None
Enable wrap. Output to attached SERDES device used to enable loopback testing of that device.
M08_EWRAP is asserted when loopback in PCSxControl = 1.
M08_GTCLK O None Transmit clock. Transmit clock output to attached SERDES device.
M08_LINK I Pulldown
Signal detect. This can be connected to the signal detect output from the external SERDES device.
– If M08_LINK = 0, there is no signal.
– If M08_LINK = 1, signal is present.
M08_LREF O None
Lock to reference. M08_LREF is asserted low during hard reset or when lckref in PortxControl = 1.
It is used by the external SERDES device to lock to its reference clock.
M08_RCLK I Pullup
Receive byte clock 0. M08_RCLK is used to input receive byte clock 0 from the attached SERDES
device.
M08_RFCLK I Pullup
Reference clock. Reference clock, used as the clock source for the transmit side of this port and
to generate M08_GTCLK. M08_RFCLK provides the clock source for the entire internal PCS
sublayer.
M08_RXD7
M08_RXD6
M08_RXD5
M08_RXD4
M08_RXD3
M08_RXD2
M08_RXD1
M08_RXD0
I Pullup
Receive data. Least significant eight bits of the 10-bit receive code group. Even-numbered code
groups are latched with M08_COL, and odd-numbered code groups are latched with M08_RCLK.
M08_RXDV I Pulldown
Receive data valid. M08_RXDV is used to receive the 9th bit of the 10-bit PMA code groups.
Even-numbered code groups are latched with M08_COL, and odd-numbered code groups are
latched with M08_RCLK.
M08_RXER I Pulldown
Receive error. M08_RXER is used to receive the 10th bit of the 10-bit PMA code groups.
Even-numbered code groups are latched with M08_COL, and odd-numbered code groups are
latched with M08_RCLK.
M08_TXD7
M08_TXD6
M08_TXD5
M08_TXD4
M08_TXD3
M08_TXD2
M08_TXD1
M08_TXD0
O None
Transmit data. Least significant eight bits of the 10-bit transmit code group. Data on these signals
is synchronous to M08_GTCLK.
M08_TXEN O None
Transmit enable. M08_TXEN is used to transmit the 9th bit of the 10-bit PMA code groups. Data
on this signal is synchronous to M08_GTCLK.
M08_TXER O None
Transmit error. M08_TXER is used to transmit the 10th bit of the 10-bit PMA code groups. Data on
this signal is synchronous to M08_GTCLK.