at91sam9g20-cu ATMEL Corporation, at91sam9g20-cu Datasheet - Page 621

• Manufacturer Part Number: at91sam9g20-cu
• Description: At91 Arm Thumb Microcontrollers
• Manufacturer: ATMEL Corporation

36. Ethernet MAC 10/100 (EMAC)
36.1
36.2
6384B–ATARM–15-Dec-08
Overview
Block Diagram
The EMAC module implements a 10/100 Ethernet MAC compatible with the IEEE 802.3 stan-
dard 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 regis-
ter 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.
The statistics register block contains registers for counting various types of event associated
with transmit and receive operations. These registers, along with the status words stored in the
receive buffer list, enable software to generate network management statistics compatible with
IEEE 802.3.
Figure 36-1. EMAC Block Diagram
Slave
APB
Master
AHB
RX FIFO
Register Interface
DMA Interface
TX FIFO
AT91SAM9G20 Preliminary
Statistics Registers
Control Registers
Address Checker
Ethernet Receive
Ethernet Transmit
MII/RMII
MDIO
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