Datasheet

• Specific address 1 filter match
• Multicast hash filter match
These events can be individually enabled through bits [19:16] of the Wake on LAN register. Also, for
Wake on LAN detection to occur, receive enable must be set in the Network Control register, however a
receive buffer does not have to be available.
In case of an ARP request, specific address 1 or multicast filter events will occur even if the frame is
errored. For magic packet events, the frame must be correctly formed and error free.
A magic packet event is detected if all of the following are true:
• Magic packet events are enabled through bit 16 of the Wake on LAN register
• The frame's destination address matches specific address 1
• The frame is correctly formed with no errors
• The frame contains at least 6 bytes of 0xFF for synchronization
• There are 16 repetitions of the contents of Specific Address 1 register immediately following the
synchronization
An ARP request event is detected if all of the following are true:
• ARP request events are enabled through bit 17 of the Wake on LAN register
• Broadcasts are allowed by bit 5 in the Network Configuration register
• The frame has a broadcast destination address (bytes 1 to 6)
• The frame has a type ID field of 0x0806 (bytes 13 and 14)
• The frame has an ARP operation field of 0x0001 (bytes 21 and 22)
• The least significant 16 bits of the frame's ARP target protocol address (bytes 41 and 42) match the
value programmed in bits[15:0] of the Wake on LAN register
The decoding of the ARP fields adjusts automatically if a VLAN tag is detected within the frame. The
reserved value of 0x0000 for the Wake on LAN target address value will not cause an ARP request event,
even if matched by the frame.
A specific address 1 filter match event will occur if all of the following are true:
• Specific address 1 events are enabled through bit 18 of the Wake on LAN register
• The frame's destination address matches the value programmed in the Specific Address 1 registers
A multicast filter match event will occur if all of the following are true:
• Multicast hash events are enabled through bit 19 of the Wake on LAN register
• Multicast hash filtering is enabled through bit 6 of the Network Configuration register
• The frame destination address matches against the multicast hash filter
• The frame destination address is not a broadcast
24.6.14 IEEE 1588 Support
IEEE 1588 is a standard for precision time synchronization in local area networks. It works with the
exchange of special Precision Time Protocol (PTP) frames. The PTP messages can be transported over
IEEE 802.3/Ethernet, over Internet Protocol Version 4 or over Internet Protocol Version 6 as described in
the annex of IEEE P1588.D2.1.
GMAC output pins indicate the message time-stamp point (asserted on the start packet delimiter and de-
asserted at end of frame) for all frames and the passage of PTP event frames (asserted when a PTP
event frame is detected and de-asserted at end of frame).
SAM D5x/E5x Family Data Sheet
GMAC - Ethernet MAC
© 2019 Microchip Technology Inc.
Datasheet
DS60001507E-page 497