TNETX15VE datasheet(8/113 Pages) TI1

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TNETX15VE

VLAN-ENGINE ADDRESS-LOOKUP DEVICE

SPWS028B – APRIL 1997 – REVISED SEPTEMBER 1997

POST OFFICE BOX 655303

• DALLAS, TEXAS 75265

Terminal Functions (Continued)

EAM interface (continued)

TERMINAL

I/O

DESCRIPTION

NAME

NO.

I/O

DESCRIPTION

When EAM15 is low, the EAM14–EAM0 terminals encode the multiple ports to which the data frame is

routed. Each bit on the EAM14–EAM0 bus is coded as follows:

– A 1 on the bit signifies that the data frame is routed to that port.

– A 0 on the bit signifies that the data frame is not routed to that port.

Terminal number assignments have a one-to-one correspondence to the port numbers as shown in the

following:

Port

EAM

bus

For example, to multicast a frame to ports 08, 05, 02, and 00 a multiport code of 0000 0001 0010 0101

or 0x0125 is sent.

Some packets, originally destined for multiple ports, need to be sent only to a single port after restrictions

are applied (VLAN, one of the destination ports = source port, etc.). TNETX15VE uses single-port coding

(EAM15 = 1) to reduce the operations required by the TNETX3150/TNETX3150A.

To discard a frame, a code of 0x0000 is output (multiple routing code with no ports selected):

TNETX3150/TNETX3150A

EAM14–EAM0

Discard Frame

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