Texas Instruments THUNDERSWITCH II TNETX4090 - Manual (Page 36)

TNETX4090
ThunderSWITCH II

9-PORT 100-/1000-MBIT/S ETHERNET

SWITCH
SPWS044E – DECEMBER 1997 – REVISED AUGUST 1999
36
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
100-/1000-Mbit/s PHY interface (port 8)
This port is controlled by an IEEE Std 802.3-compliant MAC.
speed, duplex, and flow-control negotiation
When in PMA mode and autonegotiation is enabled, the on-chip PCS layer attempts to establish a compatible
mode of operation with the attached serializer/deserializer (SERDES).
If manual override has been established, no autonegotiation takes place and the interface mode of operation
is determined by the values in Port8Control.
The PCS layer may be forced to start autonegotiation by writing a 0 and then a 1 to the neg bit in Port8Control,
but, alternatively, you could hit the newaneg bit in PCS8Control.
Figure 4 shows how the gigabit port on the TNETX4090 can be connected to a SERDES device. Table 1 gives
a description of the device terminals.
M08_RXD0–M08_RXD7
Tie to Signal Detect Terminal of
Optical Receiver, SERDES Device,
or to VCC
Serial Data
Output
Serial Data
Input
M08_TXD0–M08_TXD7
M08_TXEN
M08_TXER
TD0–TD7
TD8
TD9
SYNC
NC
VCC SYNCEN
M08_EWRAP
M08_LINK
TNETX4090
Gigabit Port Terminals
TNETE2201
(SERDES Device)
M08_LREF
M08_COL
M08_RCLK
M08_RXDV
M08_RXER
M08_GTCLK
M08_RFCLK
LOOPEN
RD0–RD7
RD8
RD9
DOUT_TXP
DOUT_TXN
DIN_RXP
DIN_RXN
LCKREFN
RBC1
RBC0
RFCLK
125-MHz Clock
NOTE: The SYNC output from the SERDES device is not used by the TNETX4090. The SYNCEN input on the SERDES device must be tied
high (enabled) for proper operation. The M08_LINK terminal on the TNETX4090 must be tied to the signal detect terminal of an attached
optical receiver or tied high if a comparable terminal is unavailable.
Figure 4. TNETX4090 Gigabit Port to SERDES Device Connections