IP1000ALF-DS-R06 datasheet(19/75 Pages) ETC2

19 / 75 page

IP1000A LF

Preliminary Data Sheet

19/75

July 5, 2005

IP1000A LF-DS-R08

Figure 2-3 : Example Magic Packet

Received Packet

0xFFFFFFFFFFFF

0x112233445566

Magic Packet wake up is controlled by the MagicPktEnable bit in the WakeEvent register. A wake event

can only take place in the D1, D2, or D3 states, and the MagicPktEnable bit has no effect when the

IP1000A LF is in the D0 power state. The Magic Packet must also pass the address matching criteria set

in ReceiveMode register. A Magic Packet may also be a broadcast frame. When the IP1000A LF detects

a Magic Packet, it signals a wake event on PMEN (if PMEN assertion is enabled), and sets the

MagicPktEvent bit in the WakeEvent register.

The IP1000A LF can also signal a wake event when it senses a change in the network link state, from

“link up” to “link fail”, or vice versa. Link state wake is controlled by the LinkEventEnable bit in the

WakeEvent register.

At the time LinkEventEnable bit is set by the host system, the IP1000A LF samples the current link state.

It then waits for the link state to change. If the link state changes before the IP1000A LF returns to state

D0 or the LinkEventEnable bit is cleared, the LinkEvent bit is set in the WakeEvent register, and (if it is

enabled) the PMEN signal is asserted.

2.3

Media Access Control

The MAC block implements the IEEE Ethernet 802.3 Media Access Control functions with Full Duplex

and Flow Control enhancements. In half duplex mode, the MAC implements the Carrier Sense Multiple

Access with Collision Detect (CSMA/CD) protocol. Full duplex mode by definition does not utilize

CSMA/CD, allowing data to be transmitted on demand. An optional flow control mechanism in full duplex

mode is provided via the MAC Control PAUSE function. Additionally, the MAC also performs these

functions in either half or full duplex mode:

Optional transmit frame check sequence (FCS) generation

Padding to the minimum legal frame size

IP1000ALF-DS-R06 数据表(PDF) 19 Page - List of Unclassifed Manufacturers