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RTL8019AS

Realtek Full-Duplex Ethernet Controller with Plug and Play Function (RealPNP)

Realtek Semiconductor 

SPECIFICATION

RTL8019AS

On power up, all PnP cards detect RSTDRV, set their CSN to 0, and enter the Wait for Key state.

There is a required 2 msec delay from either a RSTDRV or a PnP Reset command to any Plug and

Play port access to allow a card to load initial configuration information from a non-volatile device,

which is 9346 for RTL8019AS.

Cards in the Wait for Key state do not respond to any access to their auto-configuration ports until

the initiation key is detected. Cards ignore all ISA access to their Plug and Play interface.

When the cards have received the initiation key, they enter the Sleep state. In this state, the cards

listen for a Wake[CSN] command with the write data set to 00H. This wake[CSN] command will

send all cards to the Isolation state and reset the serial identifier/resource data pointer to the

beginning.

The first time the cards enter the Isolation state it is necessary to set the READ_DATA port

address using the Set RD_DATA port command. The software should then verify the selected

READ_DATA port address is not in conflict with any other devices by the isolation protocol.

Next, 72 pairs of reads are performed to the Serial Isolation register to isolate a card as described

previously. If the checksum read from the card is valid, then this means one card has been isolated.

The isolated card remains in the Isolation state while all other cards have failed the isolation

protocol and have returned to the Sleep state. The CSN on this card is set to a unique number.

Writing this value causes this card to transition to the Config state. Sending a Wake[0] command

causes this card to transition back to Sleep state and all cards with a CSN value of zero to

transition to the Isolation state. This entire process is repeated until no Plug and Play cards are

detected.

6.2.4. Reading Resource Data

Each PnP card supports a resource data structure stored in a non-volatile device (e.g. 9346) to

describe the resources supported and those requested by the functions on the card. The Plug and

Play resource management software will arbitrate resources and setup the logical device

configuration registers according to the resource data.

Card resource data may only be read from cards in the Config state. A card may get to the Config

state by one of two different methods. A card enters the Config state in response to the card

"winning" the serial isolation protocol and having a CSN assigned. The card also enters the Config

state in response to receiving a Wake[CSN] command that matches the card's CSN.

As described above, all Plug and Play cards function as if their serial identifier and their resource

data both come from the same serial device. As also stated above, the pointer to the serial device is

reset in response to any Wake[CSN] command. This implies that if a card enters the Config state

directly in response to a Wake[CSN] command, the 9-byte serial identifier must be read first

before the card resource data is accessed. The Vendor ID and Unique Serial Number is valid;

however, the checksum byte, when read in this way, is not valid. A card that enters the Config

state after the isolation protocol has been run has already accessed all 72 bits of the serial identifier

and the first read of the Resource Data register will return resource data.

8019AS.doc

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2001-04-02

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