Micrel Semiconductor

TEL:

Queue

Management

Buffer

Management

Frame

Buffers

10/100

MAC 1

10/100

MAC 2

10/100

T/TX

PHY 1

10/100

T/TX

PHY 2

EEPROM

Interface

HP Auto

MDI/MDI-X

HP Auto

MDI/MDI-X

MIB

Counters

P1 LED[3:0]

P2 LED[3:0]

EEPROM I/F

Non-PCI

CPU

Bus Interface Unit

Embedded

Processor Interface

8/16/32 Bit

Generic Host Interface

Control

Registers

Drivers

LED

1K Look-Up

Engine

DMA

Channel

Benefits

Offers all of the features of an integrated Layer 2

managed switch plus:

• Fully compliant to the IEEE 802.3u standard

• Repeater mode capabilities to allow for ‘cut-thru’ in

latency critical Industrial Ethernet or Embedded

Ethernet applications

• MAC filtering function to filter unicast packets

• Dynamic buffer memory scheme

– Essential for applications such as Video over IP

where image jitter is unacceptable

• 2-Port switch with flexible 8/16/32 bit generic host

processor interface

determine cable length, diagnose faulty cables, and

determine distance to fault

• HP Auto MDI-X crossover with disable and enable

option

available from Q4

• Four priority queues to handle voice, video, data,

and control packets

www.micrel.com

LinkMD is a trademark of Micrel, Inc.

Description

The KS8842M is the industry’s first fully managed 2-port

switch with a non-PCI CPU interface. The KS8842 is a

proven, 4th generation, integrated Layer 2 switch that is

compliant to the IEEE 802.3u standard.

The KS8842M can also be configured as a low-latency

repeater to allow for ‘cut thru’ in latency critical Embedded

or Industrial Ethernet applications. For industrial automa-

tion applications in the repeater mode, the KS8842M runs

in half-duplex mode regardless of the application.

The KS8842M offers an extensive feature set that includes

tag/port-based VLAN, QoS priority management, MAC

filtering function, MIB counters, and CPU control/data

interfaces to effectively address both current and emerg-

ing Fast Ethernet applications.

The KS8842 contains two 10/100 transceivers with pat-

ented mixed-signal low-power technology, two media ac-

cess control (MAC) units and a direct memory access

(DMA) channel, a high-speed non-blocking switch fabric,

a dedicated 1K entry forwarding table, and an on-chip

frame buffer memory.

Block Diagram

Block Diagram

Block Diagram

Block Diagram

Block Diagram

KS8842-16MQL

KS8842-32MQL

Product Brief

2-Port Ethernet Switch

with Non-PCI Interface

Applications

• Industrial applications for daisy chaining

multiple devices

• Industrial control in latency critical

applications

• Port redundancy and port monitoring

• Security cameras

• VoIP phone and ATA adaptors