KSZ9567RTXI datasheet(21/232 Pages) MICROCHIP

21 / 232 page

 2017-2019 Microchip Technology Inc.

DS00002329D-page 21

KSZ9567R

the transmission path.

• For 100BASE-TX, a simple slew-rate control method is used to minimize EMI.

• For 10BASE-Te, pre-emphasis is used to extend the signal quality through the cable.

4.1.7

AUTO-NEGOTIATION

The device conforms to the auto-negotiation protocol as described by IEEE 802.3. Auto-negotiation allows each port to

operate at either 10BASE-Te, 100BASE-TX or 1000BASE-T by allowing link partners to select the best common mode

of operation. During auto-negotiation, the link partners advertise capabilities across the link to each other and then com-

pare their own capabilities with those they received from their link partners. The highest speed and duplex setting that

is common to the two link partners is selected as the mode of operation.

The following list shows the speed and duplex operation mode from highest to lowest priority.

• Priority 1: 1000BASE-T, full-duplex

• Priority 2: 1000BASE-T, half-duplex

• Priority 3: 100BASE-TX, full-duplex

• Priority 4: 100BASE-TX, half-duplex

• Priority 5: 10BASE-Te, full-duplex

• Priority 6: 10BASE-Te, half-duplex

If the KSZ9567R link partner doesn’t support auto-negotiation or is forced to bypass auto-negotiation for 10BASE-Te

and 100BASE-TX modes, the KSZ9567R port sets its operating mode by observing the signal at its receiver. This is

known as parallel detection, and allows the KSZ9567R to establish a link by listening for a fixed signal protocol in the

absence of the auto-negotiation advertisement protocol.

The auto-negotiation link-up process is shown in Figure 4-1.

FIGURE 4-1:

AUTO-NEGOTIATION AND PARALLEL OPERATION

KSZ9567RTXI 데이터시트(PDF) 21 Page - Microchip Technology