DP83953 datasheet(18/90 Pages) NSC

18 / 90 page

4.0 Functional Description (Continued)

www.national.com

The IRB connects multiple RIC2As to realize the following

operations:

Port N Identification (which port the repeater receives

data from)

Port M Identification (which port last experienced a colli-

sion)

Data Transfer

RECEIVE COLLISION identification

TRANSMIT COLLISION identification

DISABLE OUTPUT (jabber protection)

The following table briefly describes the operation of the

Inter-RIC bus signals, the conditions required for a RIC2A

to assert a signal, and which RIC2As (in a multi-RIC2A

system) would monitor the signal.

Inter-RIC

Bus Signal

Function

Conditions Required for a RIC2A

to Drive this Signal

RIC2A Receiving the Signal

ACKI

Input signal to The PSM arbitration

chain. This chain is employed to

identify

PORT N and PORT M.

Note: A RIC2A which contains

PORT N or

PORT M may be identified by its

ACKO sig-

nal being low when its

ACKI input is high.

Not applicable

This is dependent upon the

method used to cascade

RIC2As, described in a follow-

ing section.

ACKO

Output signal from the PSM arbi-

tration chain.

If this RIC2A contains port N, then

the device will assert this signal.

This is dependent upon the

method used to cascade

RIC2As, described in a follow-

ing section.

ACTN

This signal denotes there is activity

PORT N or PORT M.

A RIC2A must contain

PORT N or

PORT M.

Note: Although this signal normally has only

one source asserting the signal active it is used

in a wired-or configuration.

The signal is monitored by all

RIC2As in the repeater system.

ANYXN

This signal denotes that a repeater

port that is not

PORT N or PORT M

is experiencing a collision.

Any RIC2A which satisfies the above

condition.

Note: This bus line is used in a wired-or config-

uration.

The signal is monitored by all

RIC2As in the repeater system.

COLN

Denotes

PORT N or PORT M is ex-

periencing a collision.

A RIC2A must contain

PORT N or

PORT M.

The signal is monitored by all

other RIC2As in the repeater

system.

IRE

This signal acts as an activity fram-

ing signal for the IRC and IRD sig-

nals.

A RIC2A must contain

PORT N.

The signal is monitored by all

other RIC2As in the repeater

system.

IRD

Decoded serial data, in NRZ for-

mat, received from the network

segment attached to

PORT N.

A RIC2A must contain

PORT N.

The signal is monitored by all

other RIC2As in the repeater

system.

IRC

Clock signal associated with IRD

and IRE.

A RIC2A must contain

PORT N.

The signal is monitored by all

other RIC2As in the repeater

system.

DP83953 Datasheet(PDF) 18 Page - National Semiconductor (TI)

DP83953 Datasheet(HTML) 18 Page - National Semiconductor (TI)

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90

Datasheet Download

Link URL