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P4080 Development System User’s Guide, Rev. 0
14
Freescale Semiconductor
Architecture
5.1.3
Ethernet (EC)
The P4080 supports up to two 10/100/1000baseT triple-speed Ethernet controllers (EC). The P4080DS
uses one of these, which is channel EC2, and is connected to the on-board Vitesse VSC8244 PHY (the
remaining ports are unused) using the RGMII protocol. Alternately, both ECs may be independently
connected to a ULPI USB interface; for the P4080DS, EC1 routes via ULPI to a USB PHY. See
,” for more information.
This table summarizes connections and routing.
This figure shows the general organization of the Ethernet system.
Figure 7. Ethernet Architecture
The P4080DS uses the ICS8304AMLF to drive the Ethernet GTX clocks with the correct edge rate at
2.5 V.
See the Vitesse website for programming information for the VSC8244 PHY.
Table 6. Ethernet Port Locations
P4080 EC #
Connection Port
PHY Address
Location
Notes
2
EC
0
Top port of stack
—
1
USB
na
Bottom port of stack
—
P4080
MI
CLKBUF
EC #2
EC #1
VSC8244
0
1
2
3
GTXCLK
Port #1
USB Ports
125 MHz
To USB