Problem in controlling FFT megacore function???

[Altera_Forum]

Hi, I'm currently working in a project, in which I use FFT block to correlate signal. I got stuck in simulating the fft block. My block do fft for 1024 points. I use a clock 1Mhz to clock.  

I simulated in modelsim with : -I assert port reset, sink_valid, sink_ready to '1' and sink_error, inverse to "00", '0'...  -For 1024 points FFT, there 1024 clock cycles between sink_sop and sink_eop  but the outputs stuck a zero, Where did I do wrong?  By the way, what 's the standard method to control fft megacore block when I have to control sink_eop and sink_sop, clock, reset... Can I use sink_sop and sink_eop from one source? Because they have same form ( In streaming data flow chart in user guide megacore fft 11.)

[Altera_Forum]

This could be a couple of things. 

 Have you asserted source_ready? Have you included a global clock enable, which will also need to be asserted? What are you using for your input?

[Altera_Forum]

--- Quote Start ---  This could be a couple of things.  Have you asserted source_ready? Have you included a global clock enable, which will also need to be asserted? What are you using for your input?  --- Quote End ---    Thanks, I got it done by using a small state machine to control sop and eop, the source_ready is set to '1'. and then WAIT for 2x1024 clock cycles. I didin't wait for such a long time. But still question, why distance between sop and eop is 1024? what 's different if I use distance between sop and eop other than FFT points? By the way, I didn't use **** enable. Is that ok? The use 8 bit input for PRN code. That's wasted!!!! ]

[Altera_Forum]

It's fine to not use clk enable so long as you didn't select it as an option when you created the function. 

 I'm not sure I understand your SOP and EOP question, how are you trying to generate it from one source?   The SOP and EOP need to indicate the packet size to the FFT engine. I haven't tested it myself, but if you set the distance between the two to longer than the packet length, I imagine it's going to continually overwrite the final value until the EOP signal is received.

[Altera_Forum]

--- Quote Start ---  It's fine to not use clk enable so long as you didn't select it as an option when you created the function.  I'm not sure I understand your SOP and EOP question, how are you trying to generate it from one source?   The SOP and EOP need to indicate the packet size to the FFT engine. I haven't tested it myself, but if you set the distance between the two to longer than the packet length, I imagine it's going to continually overwrite the final value until the EOP signal is received.  --- Quote End ---   Thank's @el07dm