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AN1301 APPLICATION NOTE

6.0 LED PINS

The LED display, consists of five LEDs having the following characteristics:

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Speed LED: 100Mbps(on) or 10Mbps(off)

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Transmit/Receive LED: Blinks at 10Hz when transmitting or receiving, but not colliding

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10Mbps LED: Blinks at 10Hz when transmitting, but not colliding

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Link LED: On when 100M or 10M link ok

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Collision/FD LED: Blinks at 20Hz to indicate a collision. On to indicate full duplex operation

7.0 TYPICAL APPLICATION

While the STE100P may be used in a variety of applications such as multi-port repeaters or switches, the

application shown below gives a very simple way of evaluating and using the STE100P with minimum cir-

cuitry. (Refer to Bill of Materials in Table 2)

A typical application of the STE100P presented here would be in designing a Fast Ethernet transceiver

with a standard MII interface and a 10/100 Mbps twisted pair connector. (Refer to Fig. 5)

In this application,

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STE100P is the only IC needed.

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It connects directly to the industry standard 40-pin MII connector.

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It also connects to the RJ-45 jack via a standard Fast Ethernet transformer.

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5, 4-position DIP switches are used to select the PHY address. (More details on the PHY address reg-

isters, etc. are available on the STE100P datasheet)

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2, 10-position DIP switches are used for determination of all of the pin-selectable options of the

STE100P such as duplex mode, data rate and auto negotiation.

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STE100P also supports the MII MDIO access to all of its internal registers.

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LEDs are included to indicate status information such as speed, duplex mode, transmit and receive ac-

tivity and link status.

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There are registers with 16 bits each supported for STE100P. (More details on these registers are avail-

able in the STE100P datasheet).

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There are also 4 special registers for advanced chip control and status information.

7.1 Schematics

The schematics for the sample application can be found on the the following page and the ST website at:

http://www.st.com/prodpres/dedicate/telecom/network/datacom/st100p.htm