SMSC LAN9420i Manual De Usuario

Single-Chip Ethernet Controller with HP Auto-MDIX Support and PCI Interface

SMSC LAN9420/LAN9420i

59

Revision 1.22 (09-25-08)

 indicates the cases that produce a wake when the 

of the 

 is set. All other cases do not generate a wake.

As determined by bit 0 of Filter i Command.

CRC matches Filter i CRC-16 field.

As determined by bit 9 of WUCSR.

As determined by bit 2 of Filter i Command.

Note: x indicates “don’t care”.

Setting the Magic Packet Enable bit (MPEN) in the 

, places the MAC in the “Magic Packet” detection mode. In this mode,

normal data reception is disabled, and detection logic within the MAC examines receive data for a
Magic Packet. The MAC can be programmed to assert the wake event interrupt to the Interrupt
Controller on detection. Upon detection, the Magic Packet Received bit (MPR) in the WUCSR is set.
When the Host clears the MPEN bit, normal receive operation will resume. Please refer to 

 for additional information on this

register

In Magic Packet mode, logic within the MAC constantly monitors each frame addressed to the node
for a specific Magic Packet pattern. It checks only packets with the MAC’s address or a broadcast
address to meet the Magic Packet requirement. The MAC checks each received frame for the pattern
48’hFF_FF_FF_FF_FF_FF after the destination and source address field.

15:0

Pattern CRC-16: This field contains the 16-bit CRC value from the pattern and the byte mask 
programmed to the wakeup filter register function. This value is compared against the CRC 
calculated on the incoming frame, and a match indicates the reception of a wakeup frame.

Yes

Yes

x

x

x

Yes

No

No

Yes

Yes

Yes

x

x

No

No

Yes

Yes

Yes

x

Yes

Multicast

(=1)

No

Yes

No

Yes

Yes

x

Yes

Unicast

(=0)

No

No

Yes