User manual

Hardware Description
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The USB device port can also be implemented to power on the board. One I/O line may be
used by the application to check that VBUS is still available from the host. Self-powered
devices may use this entry to be notified that the host has been powered off. In this case,
the pullup on DP must be disabled in order to prevent feeding current to the host. The
application should disconnect the transceiver, then remove the pullup.
5.23. Ethernet MAC (EMAC)
The EMAC module implements a 10/100 MBit/s Ethernet MAC compatible with the IEEE
802.3 standard using an address checker, statistics and control registers, receive and
transmit blocks, and a DMA interface.
The address checker recognizes four specific 48-bit addresses and contains a 64-bit hash
register for matching multicast and unicast addresses. It can recognize the broadcast
address of all ones, copy all frames, and act on an external address match signal.
An individual 48-bit MAC address (ETHERNET hardware address) is allocated to each
product. This number is stored in flash memory. It is recommended not to change the MAC
address in order to comply with IEEE Ethernet standards.
To completely implement ethernet an additional physical layer interface is needed (PHY).
A sample implementation is found on the Starterkit Board. The EMAC is not present
on all variations of the StampA5D3x series. Compare Table 2.1, “SAMA5D3X Device
Differences”.
5.24. Gigabit Ethernet MAC (GMAC)
The GMAC module implements a 10/100/1000 MBit/s Ethernet Gigabit MAC compatible
with the IEEE 802.3 standard using an address checker, statistics and control registers,
receive and transmit blocks, and a DMA interface.
The address checker recognizes four specific 48-bit addresses and contains a 64-bit hash
register for matching multicast and unicast addresses. It can recognize the broadcast
address of all ones, copy all frames, and act on an external address match signal.
An individual 48-bit MAC address (ETHERNET hardware address) is allocated to each
product. This number is stored in flash memory. It is recommended not to change the MAC
address in order to comply with IEEE Ethernet standards.
To completely implement ethernet an additional physical layer interface is needed (PHY).
Only RGMII is supported on on the StampA5D3x series The GMAC is not present
on all variations of the StampA5D3x series. Compare Table 2.1, “SAMA5D3X Device
Differences”.
5.25. Controller Area Network (CAN)
The CAN controller provides all features required to implement the serial communication
protocol. It is fully compliant with CAN 2.0 Part A and Part B specifications. Part A or B
specification is independently programmable for each message.
It supports bit rates up to 1 Mbit/s and handles data, remote, error and overload frames.