AM79C961A HTML VIEW PDF DOWNLOAD , AM79C961A Hoja de datos -Advanced Micro Devices DATASHEETBANK...

AM79C961A(1996) Ver la hoja de datos (PDF) - Advanced Micro Devices

Número de pieza

componentes Descripción

Lista de partido

AM79C961A
(Rev.:1996)

PCnet™-ISA II Jumperless, Full Duplex Single-Chip Ethernet Controller for ISA

Advanced Micro Devices

AM79C961A Datasheet PDF : 85 Pages

1 2 3 4 5 6 7 8 9 10 Next Last

PRELIMINARY

GENERAL DESCRIPTION

The PCnet-ISA II controller, a single-chip Ethernet con-

troller, is a highly integrated system solution for the

PC-AT Industry Standard Architecture (ISA) architec-

ture. It is designed to provide ﬂexibility and compatibil-

ity with any existing PC application. This highly

integrated 132-pin VLSI device is speciﬁcally designed

to reduce parts count and cost, and addresses applica-

tions where higher system throughput is desired. The

PCnet-ISA II controller is fabricated with AMD’s

advanced low-power CMOS process to provide low

standby current for power sensitive applications.

The PCnet-ISA II controller can be conﬁgured into one

of three different architecture modes to suit a particular

PC application. In the Bus Master mode, all transfers

are performed using the integrated DMA controller.

This conﬁguration enhances system performance by

allowing the PCnet-ISA II controller to bypass the plat-

form DMA controller and directly address the full 24-bit

memory space. The implementation of Bus Master

mode allows minimum parts count for the majority of

PC applications. The PCnet-ISA II can also be conﬁg-

ured as a Bus Slave with either a Shared Memory or

Programmed I/O architecture for compatibility with

low-end machines, such as PC/XTs that do not support

Bus Masters, and high-end machines that require local

packet buffering for increased system latency.

The PCnet-ISA II controller is designed to directly inter-

face with the ISA or EISA system bus. It contains an

ISA Plug and Play bus interface unit, DMA Buffer Man-

agement Unit, 802.3 Media Access Control function,

individual 136-byte transmit and 128-byte receive

FIFOs, IEEE 802.3 deﬁned Attachment Unit Interface

(AUI), and a Twisted Pair Transceiver Media Attach-

ment Unit. Full duplex network operation can be

enabled on any of the device’s network ports. The

PCnet-ISA II controller is also register compatible with

the LANCE (Am7990) Ethernet controller and

PCnet-ISA. The DMA Buffer Management Unit sup-

ports the LANCE descriptor software model. External

remote boot and Ethernet physical address PROMs

and Electrically Erasable Proms are also supported.

This advanced Ethernet controller has the built-in

capability of automatically selecting either the AUI port

or the Twisted Pair transceiver. Only one interface is

active at any one time. The individual 136-byte transmit

and 128-byte receive FIFOs optimize system over-

head, providing sufﬁcient latency during packet trans-

mission and reception, and minimizing intervention

during normal network error recovery. The integrated

Manchester encoder/decoder eliminates the need for

an external Serial Interface Adapter (SIA) in the node

system. If support for an external encoding/decoding

scheme is desired, the embedded General Purpose

Serial Interface (GPSI) allows direct access to/from the

MAC. In addition, the device provides programmable

on-chip LED drivers for transmit, receive, collision,

receive polarity, link integrity and activity, or jabber

status. The PCnet-ISA II controller also provides an

External Address Detection InterfaceTM (EADITM) to

allow external hardware address ﬁltering in internet-

working applications.