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I want to know if the TCP/IP Stack in NIOS II can control my DM9000A chip immediately?
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Quick answer is No.
Insight is this: The TCP/IP Stack is a set of call routines which the processor uses to communicate with the MAC layer to establish connections, read and write data into sockets, etc. It is basically the processor which communicates (I prefer to use "communicate" rather than "control") with the MAC + PHY layer.
Suppose you have TCP/IP Stack and the processor which connects to the right ports of the DM9000A chip. But that's not enough. Your processor would also need drivers for this chip. So essentially TCP/IP comes into picture much later. First you need to connect your processor to your chip and have compiled drivers. Then write a program for handling data over Ethernet using TCP/IP stack call routines.
