KS8993F-A1 Micrel Inc, KS8993F-A1 Datasheet - Page 29

• Manufacturer Part Number: KS8993F-A1
• Description: IC CONV MED 10/100 3PORT 128PQFP
• Manufacturer: Micrel Inc

Specifications of KS8993F-A1

• Applications: *
• Mounting Type: Surface Mount
• Package / Case: 128-MQFP, 128-PQFP
• For Use With: KS8993F-EVAL - EVAL KIT EXPERIMENTAL KS8993F
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

KS8993F
2.3.10 Auto Negotiation
The KS8993F conforms to the auto negotiation protocol as described by the 802.3 committee. Auto negotiation allows
UTP (Unshielded Twisted Pair) 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 KS8993F is forced to bypass auto negotiation, then 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 set up is depicted in the following flow diagram.
2.4
2.4.1
The internal look up table stores MAC addresses and their associated information. It contains a 1K uni-cast address
table plus switching information. The KS8993F is guaranteed to learn 1K addresses and distinguishes itself from
hash-based look up tables, which depending on the operating environment and probabilities, may not guarantee the
absolute number of addresses it can learn.
2.4.2
The internal look up engine will update its table with a new entry if the following conditions are met:
August 26, 2004
MAC and Switch Function
Address Look Up
Learning
Bypass Auto Negotiation
Start Auto Negotiation
and Set Link Mode
Force Link Setting
Yes
Figure 3: Auto Negotiation and Parallel Detection
Attempt Auto
Negotiation
No
- 29 -
Listen for 100BaseTX
Link Mode Set ?
Link Mode Set
Operation
Join Flow
Parallel
Idles
Yes
Listen for 10BaseT Link
Pulses
No
Revision 1.0
Micrel