www.micrel.com
PMQL/PMQLI
Product Brief
KSZ8842
2-Port Ethernet Switch with
PCI Interface
Description
The KSZ8842-PMQL is the industry鈥檚 铿乺st 2-port switch
with a PCI CPU interface. An Industrial Temperature
grade part, the KSZ8842-PMQLI will also available from
Q1, 2006. The KSZ8842P is a proven, 4th generation,
integrated, fully managed Layer 2 switch that is entirely
compliant to IEEE802.3u standards.
The KSZ8842P can be con铿乬ured as a low-latency re-
peater to allow for 鈥榗ut thru鈥?in latency critical Embedded or
Industrial Ethernet applications. For industrial automation
applications, it runs in half-duplex mode.
Bene铿乼s
The KSZ8842P offers an extensive feature set that includes
tag/port-based VLAN, QoS priority management, MAC
铿乴tering function, MIB counters, and CPU control/data
interfaces to effectively address both current and emerg-
ing Fast Ethernet applications.
The KSZ8842P contains two 10/100 transceivers with
patented mixed-signal low-power technology, two 1K
entry media access control (MAC) units, a separate
DMA channel, a high-speed non-blocking switch fabric,
a dedicated 1K entry forwarding table, and an on-chip
frame buffer memory.
In addition to offering all of the features of an integrat-
ed Layer 2 managed switch:
鈥?2-port switch with 32 bit/33MHz PCI bus for differ-
ent host processor interfaces
鈥?Fully compliant to the IEEE802.3u standard
鈥?Repeater mode capabilities to allow for 鈥榗ut-thru鈥?/div>
in latency critical Industrial Ethernet or Embedded
Ethernet applications
鈥?Dynamic buffer memory scheme
鈥?Essential for applications such as Video over IP
where image jitter is unacceptable
鈥?Micrel LinkMD
TM
cable diagnostic capabilities to
determine cable length, determine distance to fault,
and to diagnose faulty cables
鈥?HP Auto MDIX crossover with disable and enable
option
鈥?Industrial temperature support: 鈥?0
o
C to +85
o
C
鈥?Four priority queues to handle voice, video, data,
and control packets
Block Diagram
HP Auto
MDI/MDI-X
HP Auto
MDI/MDI-X
10/100
T/TX
PHY 1
10/100
MAC 1
1K Look-up
Engine
FIFO, Flow Control, VLAN Tagging, Priority
10/100
T/TX
PHY 2
10/100
MAC 2
Queue
Management
PCI Bus
Interface
32 Bit/33MHz
PCI
Interface Unit
DMA
Channel
Buffer
Management
Frame
Buffers
MIB
Counters
Control
Registers
EEPROM
Interface
EEPROM I/F
P1 LED[3:0]
P2 LED[3:0]
LED
Drivers
Note: For an MII/RMII, I
2
C or SPI interface, use the KSZ8893ML.
LinkMD is a trademark of Micrel, Inc.
Micrel Semiconductor
TEL:
1.408.944.0800
FAX:
1.408.474.1000
HTTP://
www.micrel.com
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