KS8721SL-EVAL Micrel Inc, KS8721SL-EVAL Datasheet - Page 23

• Manufacturer Part Number: KS8721SL-EVAL
• Description: BOARD EVAL EXPERIMENT KS8721SL
• Manufacturer: Micrel Inc

Specifications of KS8721SL-EVAL

• Main Purpose: Interface, Ethernet Controller (PHY and MAC)
• Embedded: No
• Utilized Ic / Part: KSZ8721SL
• Primary Attributes: 1 Port, 100BASE-TX/100BASE-FX/10BASE-T
• Secondary Attributes: MII, RMII, Auto MDI, MDIX, >130 Meter Cable Driver, LDO, IEEE802.3u Compliant
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 576-1010

KS8721BL/SL (3.3V Single Power Supply 10/100BaseTX/FX MII Physical Layer Transceiver)
Auto-negotiation
MII Management Interface
The KS8721BL/SL performs auto-negotiation by hardware strapping
option (pin 29) or software (Register 0.12). It will automatically
choose its mode of operation by advertising its abilities and
comparing them with those received from its link partner whenever
auto-negotiation is enabled. It can also be configured to advertise
100BaseTX or 10BaseT in either full- or half-duplex mode (please
refer to page 11 and 12 for setting). The auto-negotiation is
disabled in the FX mode.
During auto-negotiation, the contents of Register 4, coded in Fast
Link Pulse (FLP), will be sent to its link partner under the conditions
of power-on, link-loss or re-start. At the same time, the
KS8721BL/SL will monitor incoming data to determine its mode of
operation. Parallel detection circuit will be enabled as soon as either
10BaseT NLP (Normal Link Pulse) or 100BaseTX idle is detected. The
operation mode is configured based on the following priority:
When the KS8721BL/SL receives a burst of FLP from its link partner
with 3 identical link code words (ignoring acknowledge bit), it will
store these code words in Register 5 and wait for the next 3 identical
code words. Once the KS8721BL/SL detects the second code words,
it then configures itself according to above-mentioned priority. In
addition, the KS8721BL/SL also checks 100BaseTX idle or 10BaseT
NLP symbol. If either is detected, the KS8721BL/SL automatically
configures to match the detected operating speed.
The KS8721BL/SL supports the IEEE 802.3 MII Management
Interface, also known as the Management Data Input / Output
(MDIO) Interface. This interface allows upper-layer devices to
monitor and control the state of the KS8721BL/SL. The MDIO
interface consists of the following:
Priority 1: 100BaseTX, full-duplex
Priority 2: 100BaseTX, half-duplex
Priority 3: 10BaseT, full-duplex
Priority 4: 10BaseT, half-duplex
A physical connection including a data line (MDIO), a clock
line (MDC) and an optional interrupt line (INTRPT)
A specific protocol that runs across the above-mentioned
physical connection and it also allows one controller to
communicate with multiple KS8721BL/SL devices. Each
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KS8721BL/SL Preliminary Rev 0.90
Aug, 2003