Intel Video Game Controller Intel Gigabit Ethernet Controllers Manual De Usuario

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The Ethernet controller generates a wakeup event after receiving any packet whose destination 
address matches one of the 16 valid programmed Receive Addresses if the Directed Exact Wakeup 

bit is set in the Wakeup Filter Control Register (WUFC.EX).

For multicast packets, the upper bits of the incoming packet’s destination address indexes a bit 

vector (Multicast Table Array) that indicates whether to accept the packet. If the Directed Multicast 

 bit set in the Wakeup Filter Control Register (WUFC.MC) and the indexed bit in 

the vector is one then the Ethernet controller generates a wakeup event. The exact bits used in the 

comparison are programmed by software in the Multicast Offset field of the Receive Control 

Register (RCTL.MO).

If the Broadcast Wakeup Enable bit in the Wakeup Filter Control Register (WUFC.BC) is set, the 

Ethernet controller generates a wakeup event when it receives a broadcast packet.

Magic Packet* technology is defined at: http://www.amd.com/products/npd/overview/20212.html.

The Ethernet controller expects the destination address to:

1. Be the broadcast address (FF.FF.FF.FF.FF.FF)

2. Match the value in Receive Address Register 0 (RAH0, RAL0). This is initially loaded from 

the EEPROM but can be changed by the software driver.

3. Match any other address filtering enabled by the software driver.

The Ethernet controller searches for the contents of Receive Address Register 0 (RAH0, RAL0) as 

the embedded IEEE address. It considers any non FF byte after a series of at least 6 FFs to be the 

start of the address for comparison purposes (for example, it catches the case of 7 FFs followed by 
the address). As soon as one of the first 96 bytes after a string of FFs doesn’t match, it continues to 

search for anther set of at least 6 FFs followed by the 16 copies of the IEEE address later in the 

packet. Note that this definition precludes the first byte of the destination address from being FF.

0

6

Destination Address

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Match any pre-
programmed address

0

6

Destination Address

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0

6

Destination Address

FF*6

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1.

Not applicable to the 82541ER.