TNETX3270

ThunderSWITCH24/3 ETHERNETSWITCH

WITH 24 10-MBIT/S PORTS AND 3 10-/100-MBIT/S PORTS

SPWS043B ± NOVEMBER 1997 ± REVISED APRIL 1999

Table 11. 10-Mbit/s Interface Connections

TNETX3270

 

 

TNETE2008

 

TERMINAL

 

 

TERMINAL

 

 

 

 

 

 

 

 

THxCLK

 

IFCLK

 

 

 

 

 

 

 

 

THxSYNC

 

IFSYNC

 

 

 

 

 

 

 

 

THxCOL

 

IFCOL

 

 

 

 

 

 

 

 

THxCRS

 

IFCRS

 

 

 

 

 

 

 

 

THxLINK

 

IFLINK

 

 

 

 

 

 

 

 

THxRXD3

 

IFRXD3

 

 

 

 

 

 

 

 

THxRXD2

 

IFRXD2

 

 

 

 

 

 

 

 

THxRXD1

 

IFRXD1

 

 

 

 

 

 

 

 

THxRXD0

 

IFRXD0

 

 

 

 

 

 

 

 

THxRXDV

 

IFRXDV

 

 

 

 

 

 

 

 

THxTXD3

 

IFTXD3

 

 

 

 

 

 

 

 

THxTXD2

 

IFTXD2

 

 

 

 

 

 

 

 

THxTXD1

 

IFTXD1

 

 

 

 

 

 

 

 

THxTXD0

 

IFTXD0

 

 

 

 

 

 

 

 

THxTXEN

 

IFTXEN

 

 

 

 

 

 

 

 

 

 

 

 

THxRENEG

 

 

IFFORCEHD

 

 

 

 

 

 

Where x = 0, 1, or 2

 

 

 

 

The time multiplexing of this interface is shown in Figure 6. The interface runs synchronous to the PHY-generated 20-MHz clock IFCLK. The MAC-to-PHY information for the first port in each group of eight (i.e., port 00, port 08, or port 16) is presented on the interface when the THxSYNC terminal is high. The next clock cycle that the interface carries is the information for the second port. This process continues for all eight ports, each using the interface for one cycle. When all ports have been processed in this manner, the sequence resumes with the first port and again when the THxSYNC signal is asserted.

To improve latency-related issues, the PHY-to-MAC data are skewed by two slots, allowing the MAC to respond to the input signals from the PHY in the same 400-ns cycle, rather than waiting for the next 400-ns cycle (which would be the case if the signals were not skewed).

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Texas Instruments specifications Mbit/s Interface Connections, TNETX3270 TNETE2008 Terminal