Altera Corporation
Reference Manual
2–13
May 2007
Nios Development Board Cyclone II Edition
Board Components
Ethernet
MAC/PHY (U4) &
RJ45 Connector
(RJ1)
The LAN91C111 chip (U4) is a 10/100 Ethernet media access control and
physical interface (MAC/PHY) chip. The control pins of U4 are
connected to the FPGA so that Nios II systems can access Ethernet
networks via the RJ-45 connector (RJ1) as shown in
Nios II development tools include hardware and software components
that allow Nios II processor systems to communicate with the
LAN91C111 Ethernet device.
Figure 2–4. Ethernet RJ-45 Connector
Refer to
for connections between the FPGA and the MAC/PHY
device.
1
The Ethernet MAC/PHY device shares both address and data
connections with the flash memory.
Table 2–9. Ethernet MAC/PHY Pin Table
FPGA Pin
U4 Pin
Pin Function
Board Net Name
(1)
E26
41
Address Enable
enet_aen
J17
43
Synchronous Ready
enet_srdy_n
F18
40
VL Bus Access
enet_vlbus_n
G18
45
Local Device
enet_ldev_n
D18
38
IO Char Ready
enet_iochrdy
E18
37
Address Strobe
enet_ads_n
A19
42
Local Bus Clock
enet_lclk
B19
46
Ready/Return
enet_rdyrtn_n
D20
35
Bus Cycle
enet_cycle_n
D14
36
Write/Read
enet_w_r_n
Y15
34
Bus Chip Select
enet_datacs_n
AA15
29
Interrupt
enet_intr0
RJ1
U4