SIGMA DE2-70 - Manual (Page 81)

DE2-70 User Manual
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Clock/Data
Frequency
Generator
Speaker
MP3/Any Audio Output
Microphone
Figure 6.10. The setup for the Karaoke Machine.
6.7 Ethernet Packet Sending/Receiving
In this demonstration, we will show how to send and receive Ethernet packets using the Fast
Ethernet controller on DE2-70 board. As illustrated in Figure 6.11, we use the Nios II processor to
send and receive Ethernet packets using the DM9000A Ethernet PHY/MAC Controller. The
demonstration can be set up to use either a loop-back connection from one board to itself, or two
DE2-70 boards connected together.
On the transmitting side, the Nios II processor sends 64-byte packets every 0.5 seconds to the
DM9000A. After receiving the packet, the DM9000A appends a four-byte checksum to the packet
and sends it to the Ethernet port.
On the receiving side, the DM9000A checks every packet received to see if the destination MAC