PRELIMINARY

This document contains information on a product under development at Advanced Micro Devices. The

information is intended to help you evaluate this product. AMD reserves the right to change or discontinue

work on this proposed product without notice.

Publication# 17305

Rev: B Amendment/0

Issue Date: May 1994

1

Am79C987

Hardware Implemented Management Information Base™

(HIMIB™) Device

DISTINCTIVE CHARACTERISTICS

s Provides repeater management functions,

complying with all options detailed in the layer

management for 10 Mbyte/s Baseband

Repeaters (IEEE 802.3k) standard

s Fully compatible with the Novell Hub

Management Interface (HMI) specification

s Provides additional IEEE MAU management

functions (802.3p draft)

s Interfaces directly with AMD’s Am79C981

Integrated Multiport Repeater Plus™ (IMR+™)

device to build a fully managed repeater

s Multiple HIMIB/IMR+ devices can be used in a

system

s 8-bit microprocessor interface allows attribute

access, interrupt control, and management

control

s Maskable interrupts for notification of status/

error reporting

s Internal “receive only” MAC tracks all address

information and monitors exception conditions

s Supports mapping of node source addresses to

port numbers, through implementing source

address match function

s Full 32-bit hardware-implemented counters

incur no additional software overhead to keep

network statistics

s Pinout allows simple board layout between

IMR+ and HIMIB devices

s 28-pin PLCC device in CMOS technology for low

power with a single +5 V supply

GENERAL DESCRIPTION

The Am79C987 Hardware Implemented Management

Information Base (HIMIB) device is a highly integrated

chip that simplifies building fully managed multiport re-

peaters. The device integrates all the necessary

counters, attributes, actions, and notifications specified

by the Layer Management for 10 Mbyte/s Baseband

Repeaters (IEEE 802.3k) standard, as well as addi-

tional features and enhancements, including functions

specific to 10BASE-T repeaters.

The HIMIB chip is designed to be used in conjunction

with AMD’s Integrated Multiport Repeater Plus (IMR+)

device. When connected to an IMR+ (Am79C981)

device, the HIMIB chip provides complete repeater and

per-port statistics on demand from an 8-bit parallel in-

terface. No external processor is required to keep track

of attributes locally, as full 32-bit counters are provided.

The HIMIB device implements a simple 8-bit micropro-

cessor interface, allowing multiple HIMIB devices to be

used in a system. No additional logic is required for in-

terfacing the HIMIB device to the IMR+ device.

The HIMIB chip is packaged in a 28-pin plastic leaded

chip carrier (PLCC). The device is fabricated in CMOS

technology and requires a single +5 V supply.