KSZ8842-PMBLAM MICREL [Micrel Semiconductor], KSZ8842-PMBLAM Datasheet - Page 23

• Manufacturer Part Number: KSZ8842-PMBLAM
• Description: 2-Port Ethernet Switch with PCI Interface
• Manufacturer: MICREL [Micrel Semiconductor]

Micrel, Inc.
KSZ8842-PMQL/PMBL
Crossover Cable
A crossover cable connects an MDI device to another MDI device, or an MDI-X device to another MDI-X device. The
following diagram shows a typical crossover cable connection between two switches or hubs (two MDI-X devices).
Figure 5. Typical Crossover Cable Connection
Auto Negotiation
The KSZ8842-PMQL/PMBL conforms to the auto negotiation protocol as described by the 802.3 committee to allow the
channel to operate at 10Base-T or 100Base-TX.
Auto negotiation allows unshielded twisted pair (UTP) link partners to select the best common mode of operation. In
auto negotiation, the link partners advertise capabilities across the link to each other. If auto negotiation is not
supported or the link partner to the KSZ8842-PMQL/PMBL is forced to bypass auto negotiation, the mode is set by
observing the signal at the receiver. This is known as parallel mode because while the transmitter is sending auto
negotiation advertisements, the receiver is listening for advertisements or a fixed signal protocol.
The link setup is shown in the following flow diagram (Figure 6).
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October 2007
M9999-100207-1.5