EMAC Block Diagram and System Integration
Figure 17-1: EMAC System Integration
EMAC integration from a high level point of view.
PHY
Transceiver
PHY
FPGA Fabric
PHY
EMAC0
PHY
MDIO
TMSTP
DMA
CSR
EMAC1
I
2
C
(For Ethernet)
L3
Interconnect
Pin
Multiplexer
HPS
2
GMII/MII/MDIO
RGMII
MDIO/
I
2
C
AXI
APB
Legend
TMSTP = Timestamp
The EMACs are integrated into the HPS portion of the system on a chip (SoC) FPGA device. They
communicate with the I/O pins.
EMAC to RGMII Interface
Table 17-1: External PHY Datapath In/Out Interface
Description
Width
In/Out
EMAC Port
Transmit Clock. This signal provides the
transmit clock for RGMII (125/25/2.5 MHz in
1G/100M/10Mbps). All PHY transmit signals
generated by the EMAC are synchronous to
this clock.
1
In
clk_tx_i
PHY Transmit Data. This is a group of eight
transmit data signals driven by the MAC.
Unused bits in the RGMII interface configura-
tion are tied to low. RGMII: Bits [3:0] provide
the RGMII transmit data. The data bus changes
with both rising and falling edges of the
transmit clock (clk_tx_i). The validity of the
data is qualified with phy_txen_o. Synchronous
to: clk_tx_i, clk_tx_180_i
8
Out
phy_txd_o
Altera Corporation
Ethernet Media Access Controller
17-3
EMAC Block Diagram and System Integration
cv_54017
2013.12.30