Nios II evaluation board limits

[Altera_Forum]

Is it possible to add a hardware custom instruction to a Nios II evaluation board? 

Thanks

[Altera_Forum]

Yes, custom instructions are not board-specific. CIs are bits of HDL that you can attach to the CPU using SOPC Builder. These little hardware circuits are called as macros from your software application, generally replacing a software subroutine. For more info on CIs, check out this document: 

 custom instruction user guide (http://www.altera.com/literature/ug/ug_nios2_custom_instruction.pdf)  Also, there's an online demo available that will walk you through the steps needed to add a custom instruction to your design. Check it out:  http://www.altera.com/education/demonstrat.../onl-nios2.html (http://www.altera.com/education/demonstrations/online/embedded-processor/onl-nios2.html)

[Altera_Forum]

Hi! 

I am a beginner with VHDL and the Nios II core. I have to generate a C code to produce a sinewave from the core and I've started writing a C code using the simple sine function, but I was told it has to present commands for registers and so on...Do you know where I can find a simple sample for such a similar code? It is for a PWM code. I've done a full one with VHDL using a sinewave and a triangular one but I was told to produce the sine wave from the core. And I dont know how I 'll have to compare both signals as I did with the VHDL codes....   Thanks